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casting-msg - 8/29/08

 

Casting pewter and other metals.

 

NOTE: See also these files: cast-cutlefsh-msg, metals-msg, metalworking-msg, metalworking-FAQ, tokens-msg, belts-msg, fasteners-msg, soapstone-msg, pewter-msg.

 

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NOTICE -

 

This file is a collection of various messages having a common theme that I have collected from my reading of the various computer networks. Some messages date back to 1989, some may be as recent as yesterday.

 

This file is part of a collection of files called Stefan's Florilegium. These files are available on the Internet at: http://www.florilegium.org

 

I have done a limited amount of editing. Messages having to do with separate topics were sometimes split into different files and sometimes extraneous information was removed. For instance, the message IDs were removed to save space and remove clutter.

 

The comments made in these messages are not necessarily my viewpoints. I make no claims as to the accuracy of the information given by the individual authors.

 

Please respect the time and efforts of those who have written these messages. The copyright status of these messages is unclear at this time. If information is published from these messages, please give credit to the originator(s).

 

Thank you,

    Mark S. Harris                  AKA:  THLord Stefan li Rous

                                          Stefan at florilegium.org

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From: sclark at epas.utoronto.ca (Susan Carroll-Clark)

Newsgroups: rec.org.sca

Subject: Pewter Casting article...

Date: 4 Jul 1994 03:12:10 GMT

Organization: University of Toronto -- EPAS

 

Greetings...

      Hot off the presses, here's the promised article.

Happy reading...

 

Nicolaa/Susan

sclark at epas.utoronto.ca

 

*******************************************************************************

 

Beginning Pewter Casting

by Lady Nicolaa de Bracton of Leicester

 

Materials needed:

 

--Pewter (bar or chip form).

--heat source (propane torch, stovetop element, casting pot, campfire)

--Container to heat pewter in (small pot, ladle, etc.)

--material for mold (preferably soapstone)

--rubber bands

--carving tools (dental or woodcarving tools are best, but virtually

anything will carve soapstone)

--sandpaper

--files (microfiles are most useful)

--tongs or clamps

--bowl of cold water

--pliers

--towels or oven mitts

 

A note on pewter:  Pewter sold today in craft stores for

jewellery-making is usually lead free;  it is an alloy of copper, tin,

and antimony.  A number of companies also sell pewter for miniature

casting;  this may not be lead-free.  If in doubt, ask. Current going

price for one pound of lead-free pewter in the Toronto area is $10-$17

CDN.  Craft stores are often overpriced;  ask your local SCA jewllery

- and metalworkers for sources.

 

Step 1:  The Mold

Soapstone is the best material for pewter casting.  Molds made of

soapstone rarely break down even after a hundred or more castings;

the molds retain heat quite well, which makes for good, clean casts;

and soapstone can also be carved quite finely and is very simple to

work.  If multiple castings are not needed and you have no source for

soapstone, plaster molds may also be used.  Soapstone can be obtained

from lapidary craft stores;  if you are having problems finding a

source, check with your local mineral club or art school.

 

For a simple mold, you will need two pieces of soapstone which fit

flush.  The best way to ensure that they are flush is to place a piece

of sandpaper on a flat surface and run the pieces over it repeatedly.

(Warning!  This produces lots of very fine dust.  You may wish to wear

a mask).

Once your pieces are ready, you can carve your mold.  This is entirely

up to you.  Dental tools are nice for this and can be obtained either

from your dentist (who might give you a funny look at first) or from

surplus stores.  Lapidary and jewellery-making stores sometimes stock

them as well, but they tend to be overpriced there.  Some hints:

First, make sure that your carving is no more than an inch or so from

what will be the top edge of your  mold, or else the pewter will be

cool before it ever reaches the actual mold section. Second, make sure

that there are no overhanging ledges on your mold that could trap the

pewter;  make sure that the edge of your piece is either straight or

slopes in slightly towards the bottom of the mold. Finally,  do not

carve a lot of detail onto your piece until you have done a test

casting of the basic shape.

 

Next, you need to carve a channel or *sprue* from the top edge of your

piece of soapstone to the mold itself.  The sprue should be placed

opposite from the area with the most detail, so that the pewter will

flow downward to that area first.   Your sprue should be in the shape

of a funnel, with the mouth at the edge of the piece of soapstone and

the neck close to the mold itself, and the reservoir thus created

should hold about as much pewter as the mold itself will. The larger

the piece, the bigger the sprue and reservoir.  Once you have cast

your piece, you will clip off the sprue with pliers or cutters and

file the raw edge.

 

These instructions will result in a simple one-piece mold with a back

piece.  There are such things as two- and three-piece molds, which

allow one to cast in three dimensions, but they are not suitable for

beginners.

 

Step 2:  Heating the pewter

There are many ways to do this.  I place the pewter in a ladle and

train a propane torch on it (keep the flame low--it won't take that

long to melt).  You can also find a small sauce-pot and heat it on the

stove, buy a special casting pot, or even use the hot coals of a

campfire.  Experiment around and find what works best for you.  The

most important thing is that you get the pewter hot enough to flow

through your mold.  Pewter is ready to pour when it has melted and

acquired a blackened colour on the surface.  You will want to either

have a container you can pour the pewter directly into the mold from,

or a ladle or spoon to dip into the pewter for this purpose.  The

shorter the distance from the heat source to the mold, the better;

this is why I like to heat up my pewter right in the ladle.

 

Step three:  Pouring the Pewter

Rubber-band the back of your mold to the front. (You could use

c-clamps instead, but I find them more time-consuming). At this point

it helps to have an assistant, but it is possible to manage on your

own.  Using tongs, clamp the mold together firmly, and then pour the

pewter into the reservoir.  Keep the piece clamped until the pewter

sets.  This happens when the molten pewter loses its shiny,

mercury-like appearance and turns a dull silver;  it only takes a few

seconds.  At this point, you can remove the clamp, take off the rubber

bands, and pop the casting out.  Using the pliers, place this in the

bowl of water.  DO NOT TOUCH IT!  It is still VERY hot. Watch your

mold as well -- as you continue to cast, the mold itself will heat up,

which will aid in subsequent casts; hold the mold with a towel or oven

mitts.  The first casting out of a mold is often substandard because

the mold has not yet heated up.

 

Unsuccessful casts and the sprue parts of molds can be re-fed into

your pot or ladle of pewter.  Make sure, however, that they are

THOROUGHLY DRY.  Water in the melting pot can cause the pewter to

spatter, which could cause nasty burns.

 

To finish your piece, clip off the sprue with pliers or cutters, and

file the raw edge.  You are done!

 

After a few test casts, you will probably wish to fine-tune your mold.

Here are a few common problems and possible solutions:

 

Problem:  Mold does not completely cast

This could be caused by one of two things:  either your pewter is not

hot enough, which results in the pewter setting before it has reached

all of the mold;  or your sprue is either too long or too narrow,

which causes the pewter to freeze up before it can reach the mold.

Molds which have not yet completely heat up also often do not

completely cast.

 

Problem: Pewter gets stuck in mold

Your mold probably has undercutting--a sort of overhanging ledge that

is blocking the easy removal of the cast.  File the sides so they are

either straight or slope slightly inward.

 

Problem: Pewter squirts out the side of the mold

Either your two blocks do not fit flush, or you are not clamping them

tightly enough.

 

Problem:  Loops or other details will not cast

Loops (for hanging purposes) are best put at the bottom of molds, so

that gravity will pull the pewter into them.  If details will not cast

after repeated attempts, and none of the usual solutions

(widening the sprue, making sure the pewter is very hot) do not work,

you may wish to change the location of the sprue.  You can use putty

to close up the old sprue and carve a new one.

 

The science of pewter casting is still fairly new to me, but having

survived casting 130 feast tokens over the space of two evenings and

one afternoon for an event I recently autocratted, I can honestly say

that any idiot can do it;  I am proof.  Of course, I had the help of

the very talented Lady Kestrel of Cadfan, who gave the original talk

on this topic in my home canton and who loaned me some of her

equipment and guided me through.  If you can find an experienced

caster to help, I highly recommend this approach -- youUll save a lot

of trial and error.  Good luck!

 

copyright 1994 by Susan Carroll-Clark.  Permission is granted for

publication in any SCA-related newsletter, provided that the author is

credited and receives a copy.

 

 

From: Susan Carroll-Clark (7/3/94)

To: Mark Harris

RE>Site Tokens

 

Greetinngs--

      I got my first lot of pewter from a craft supply

      store--a fairly specialized one that also deals in woodworking

      and lapidary supplies.  If you know any SCA metaworkers,

      see if they know any cheaper sources--craft stores tend

      to be pricey.  Soapstone you can get in the same sorts

      of places.  If there's an art school in your town, you might

      ask them if they know sources for these sorts of things.

 

            The tokens themselves were about nickel-thick and

      quarter-sized in diameter. The loop was part of the mold--

      it looks like a little "handle" on top of the round bit.

      Basically, here are the steps to follow:

      1.  Sand down your two sandstone pieces

      until they lie flat against each other.

      2.  Carve your mold with whatever tools you wish.  Soapstone

      carves really easily.  For best results, put the mold

      no more than an inch from the top edge of

      your stone.  Beware of undercutting: i.e., when there is

      a "ledge" in your mold that will make the pewter get

      stuck in the mold.

      3.  Carve a sprue--a channel leading to the mold,

      and a reservour for the pewter to flow into.  What you should

      end up with is a funel-shaped channel leading to your mold.

      4. Rubber band the mold to the back piece.

      5.  Heat up the pewter.  It has to get nice and hot,

      though it melts fairly quickly.  I just have a cheap

      ladle and turn the propane torch on it.When it's melted

      and starts to turn black, it's ready to pour.

      6. Using tongs, clamp onto the mold and

      then pour in the pewter. (2 people helps).

      7.  When the pewter on the top of the mold cools, you

      can pop the mold.  Pewter is ready to pop when

      it loses its shiny appearance.  Don't

      touch it, though--pop it into a dish of

      cold water first.

      8. The pewter should just pop out, if you have managed

      to avoid undercutting. Soapstone ia very similar

      in texture to talcum and so the pewter does not

      naturally stick to it.

 

      It's kind of hard to describe the process.  I had

      it shown to me--you should check around and see if there's

      anyone who can do this for you.  everyone has their

      own techniques, too--some people heat up the pewter

      right on the stove (I can't get it hot enough this

      way) and some have special pots for this (which

      I hope to acquire eventually).

 

      Good luck--

      Nicolaa/Susan

      sclark at epas.utoronto.ca

     

 

Newsgroups: rec.org.sca

From: eadengle at watcgl.uwaterloo.ca (Ed "Cynwrig" Dengler)

Subject: Re: Pewter Casting article...

Organization: University of Waterloo

Date: Tue, 5 Jul 1994 16:13:09 GMT

 

Greetings to the Rialto!

 

Nicolaa recently posted a great article on pewter casting. As another

newby who has just done a set of appreciation tokens in pewter, I would

lie to add a few points.

 

Nicolaa writes:

>A note on pewter:  Pewter sold today in craft stores for

>jewellery-making is usually lead free;  it is an alloy of copper, tin,

>and antimony.  A number of companies also sell pewter for miniature

>casting;  this may not be lead-free.  If in doubt, ask.  Current going

>price for one pound of lead-free pewter in the Toronto area is $10-$17

>CDN.  Craft stores are often overpriced;  ask your local SCA jewllery

>- and metalworkers for sources.

 

Another source of pewter recommended by Master Sylard of Eagleshavn

is to use lead-free solder sold for soldering pipes.  The big advantage

of using this is that lengths of solder wire can be snipped easily

to the quantity of pewter desired.  Note that the bigger the spool

of solder, the cheaper it gets (I bought 500g = 1.1pounds for $11).

This can be bought from any plumbing supply or hardware supply store

(warning: most solder sold contains lead, so be sure to check the

label to determine the solder mixture).

 

>Step 2:  Heating the pewter

>There are many ways to do this.  I place the pewter in a ladle and

>train a propane torch on it (keep the flame low--it wonUt take that

>long to melt).  You can also find a small sauce-pot and heat it on the

>stove, buy a special casting pot, or even use the hot coals of a

>campfire.  Experiment around and find what works best for you.  The

>most important thing is that you get the pewter hot enough to flow

>through your mold.  Pewter is ready to pour when it has melted and

>acquired a blackened colour on the surface.  You will want to either

>have a container you can pour the pewter directly into the mold from,

>or a ladle or spoon to dip into the pewter for this purpose.  The

>shorter the distance from the heat source to the mold, the better;

>this is why I like to heat up my pewter right in the ladle.

 

The method I used was to obtain a small Turkish coffee making pot made

from a heavy stainless steel, and then used a stove as a heat source.

This has the advantages that you can melt small amounts (say for only

one or two castings each time you pour), and that the pot sits nicely

on the stovetop without falling over.  Another advantage is that these

are easily obtained from any specialty cookware supply store for a

reasonable price (note that you do NOT want to make coffee in it after

using it for pewter casting).

 

>Step three:  Pouring the Pewter

>Rubber-band the back of your mold to the front. (You could use

>c-clamps instead, but I find them more time-consuming).  At this point

>it helps to have an assistant, but it is possible to manage on your

>own.  Using tongs, clamp the mold together firmly, and then pour the

>pewter into the reservoir.  Keep the piece clamped until the pewter

>sets.  This happens when the molten pewter loses its shiny,

>mercury-like appearance and turns a dull silver;  it only takes a few

>seconds.  At this point, you can remove the clamp, take off the rubber

>bands, and pop the casting out.  Using the pliers, place this in the

>bowl of water.  DO NOT TOUCH IT!  It is still VERY hot.  Watch your

>mold as well -- as you continue to cast, the mold itself will heat up,

>which will aid in subsequent casts; hold the mold with a towel or oven

>mitts.  The first casting out of a mold is often substandard because

>the mold has not yet heated up.

 

If you use reasonable size soapstone pieces, I found that you could

just hold the front and backs together with no problems. To do this,

you WILL need heavy gloves or oven mitts, since the stones get very

hot as Nicolaa has warned.

 

>Problem:  Mold does not completely cast

>This could be caused by one of two things:  either your pewter is not

>hot enough, which results in the pewter setting before it has reached

>all of the mold;  or your sprue is either too long or too narrow,

>which causes the pewter to freeze up before it can reach the mold.

>Molds which have not yet completely heat up also often do not

>completely cast.

 

One solution I have to warming up the molds is to mold 2 or 3 pieces

directly with no backing (ie. just lay your mold on the stove with

the mold facing upwards and no backing, and just pour the metal on the

mold).  This will produce an unusable cast that goes back into the

meltpot, but which has now warmed up the mold very nicely.

 

One warning when carving the molds: do NOT use water to flush away

any dust created by the carving, instead use an old toothbrush that

is dry.  The reason for this (which I found to my dismay the first

time I did castings) is that the water will get into the soapstone

and will not come back out.  When the hot pewter starts getting poured

(which melts at a temperature of 200-250 degrees Celsius), the water

is heated up and turns to steam (which occurs at 100 degrees Celsius).

This has the unpleasent effect of created a very small vapour explosion

which starts to disintegrate your mold as pieces of soapstone start to

flake off.

 

Good luck to any who want to try casting!

Cynwrig

 

 

From: dlc at fc.hp.com (Dennis Clark)

Newsgroups: rec.org.sca

Subject: Re: Pewter Casting article...

Date: 6 Jul 1994 23:34:44 GMT

Organization: Hewlett-Packard Fort Collins Site

 

Depending upon how much you want to spend, bullet "hot-pots" can be had for

the $50.00 range at auctions and estate sales.  I have two that I got from

Thrifty-nickel type rags and they both have thermostats on them.  I get my

pewter for about $6.00 US a pound (in 4 pound sets) from a place in

Albuquerque NM.  They are only a wholesale outfit so I go through a local

shop that I have befriended.  This stuff melts quite a bit hotter than the

200-250 degree metal talked about here, its more like 400-450 by my estimates

(assuming my thermostat is correct!)

 

  This article on soapstone casting is pretty cool, I have been doing things

via sand casting for years, up to making rings as an experiment right now -

I'll let others know how this works out if anyone is interested...

 

  On the less than period side, its also neat to make an entire miniature's

army yourself by using the "Prince August" or other somesuch molds and doing

it in pewter - almost seems a shame to paint them!  Darn I wish that I could

afford one of those vaccuum casting vulcanized rubber setups!!!

 

Kevin

------------------------------------------------------------------------------

| Dennis Clark  (303)229-4313   telnet 1-229-4313  email dlc at fc.hp.com       |

| Hewlett Packard ESD Perf. Lab, 3404 East Harmony Rd. Ft. Collins CO 80525  |

------------------------------CUT HERE----------------------------------------

 

 

From: Joyce Miller <jmiller at genome.wi.mit.edu>

Newsgroups: rec.org.sca

Subject: Re: Pewter Casting article...

Date: 5 Jul 1994 16:54:35 GMT

Organization: Whitehead Institute for Biomedical Research

 

In article <2v7uma$fg4 at alpha.epas.utoronto.ca> Susan

Carroll-Clark, sclark at epas.utoronto.ca writes:

>For a simple mold, you will need two pieces of soapstone which fit

>flush.  The best way to ensure that they are flush is to place a piece

>of sandpaper on a flat surface and run the pieces over it repeatedly.

>(Warning!  This produces lots of very fine dust.  You may wish to wear

>a mask).

 

Please note that soapstone is very similar to asbestos. People

using the stuff should *ABSOLUTELY* wear a mask, and should

clean up the dust with a damp paper towel.  Vaccuuming it up will

send it through the filter, and suspend it in the air.

 

-- Ursula

 

 

From: tip at lead.aichem.arizona.edu (Tom Perigrin)

Newsgroups: rec.org.sca

Subject: Re: Pewter Casting article...

Date: 5 Jul 1994 17:35:21 GMT

Organization: Department of Chemistry

 

Susan Carroll-Clark wrote:

 

[much good information snipped out]

 

> Step 1:  The Mold

 

Good My Lady,

 

I have turned my hand unto casting in various metals, an it pleases thee, I

should like to mention one other fashion of mold making that may satisfy

the needs of many another.

 

Tis true that for casting small objects with various and sundry fiddly

bits, such as would be a token, then a soapstone mold mayhaps will serve

the best.  But for larger and more mundane objects, such as a spoon, a sand

mold has much to recommend it.   I think me that for a spoon this may be

especially true, for that I myself would dispair of carving the mold so

that the two sides of the bowl of the spoon would come evenly close, and

not have the bowl be neither too thick nor too thin.   But, an one has a

spoon which pleases thee, then thou cans't use the sand mold to reproduce

it to thy hearts content.  The surface shall be slightly rough, and the

finest detail shall be lost, but with files, punches, hammer, and patience

one can remedy these small problems.   I'faith, I myself have several

spoons which I did but lightly buff, and they serve most well.

 

 

From: ayotte at milo.UUCP (Robert Arthur Ayotte)

Newsgroups: rec.org.sca

Subject: Pewter (Brittannia)

Date: 4 Jul 1994 01:59:00 -0400

Organization: the internet

 

      I would add some things on casting and working pewter.

 

      First lead free pewter (often called Britannia, which now is the

lead free form of pewter) is sometimes a mix of only tin and antimony.

There are many alloys available but all work in a similar fashion.

      A good source for these metals is NEY metals out of NY, and ARE inc

in VT.  They also carry a large supply of other metals such as copper and

nickelsilver in different sheet and wire. I have dealt with ARE and find

them very good and fast in filling orders.  In addition they carry Red Brass

and I know ARE carries Merlins Gold (another brass alloy very similar in

color to gold a much better match than standard brass).

 

      Molds - There's a dental mold making material that will take the

temperatures of pewter for small castings.  It's a fluid that sets and one

can take molds (don't forget a release coat) and then do flat casting.

There aer other rubber (silicon) materials that will take the temps of

pewter as well.  This is most useful for small scale castings.

      Sand casting, cuttelbone and charcoal blocks (the jewelr grade) will

also work for short work molds.  The results are sometimes less accurate but

will serve.  Stay away from plaster of paris as it must be baked dry and in

the small experiance I have had with it it's not a very satisfactory mold

for this application.

      You can also do a more extreme process of mold making as the

pewtersmiths (silversmiths) used to and make a hard coat sort of mold.  I

would reffer folks to "Treaties of Benvenuto Cellini on goldsmithing and

sculpture" His discriptions of mold build up for larger works are some of

the best I have read and can be down sized.  Also the works of Tim McCreight

are of great value, here his book "Practical Casting" ($10.95 US) should be

very useful, but one of the most useful is his other book "the Complete

Metalsmith".

 

      Heating - Pewter is sensative to overheating.  The Antimony tends to

seperate (that's the peacock color layer that can develop).  You want it

just hot enough to melt.  I use old cast iron pots and pans cleaned very

well and then brought to a very high temp. There are electromelt devices

available.

 

Horace, Northshield

 

 

Newsgroups: rec.org.sca

From: Ginny Beatty <virginia.l.beatty at daytonOH.NCR.COM>

Subject: Pewter - other casting materials

Organization: AT&T - GIS

Date: Tue, 5 Jul 1994 17:41:56 GMT

 

> Robert Arthur Ayotte writes:

>     I would add some things on casting and working pewter.

[snip]

>     Molds - There's a dental mold making material that will take the

>temperatures of pewter for small castings.  It's a fluid that sets and one

>can take molds (don't forget a release coat) and then do flat casting.

>There aer other rubber (silicon) materials that will take the temps of

>pewter as well.  This is most useful for small scale castings.

>     Sand casting, cuttelbone and charcoal blocks (the jewelr grade) will

>also work for short work molds.  The results are sometimes less accurate but

>will serve.  Stay away from plaster of paris as it must be baked dry and in

>the small experiance I have had with it it's not a very satisfactory mold

>for this application.

[snip]

I recently took a class on pewter casting at the Known World A&S Symposium. Lady

Caitlin (the teacher) taught the class using cuttlefish bone as the casting

medium. Granted, the detail wasn't great, but it was quite a rewarding

experience for those who have not cast metal before (read- Gwyneth learned a new

trick! Cool!:>).

 

She also recommended using Investment Plaster as a casting medium. This is not

the same as Plaster of Paris.

 

Other pewter- and silver-smiths I know use Bondo as a casting medium with fairly

successful results.

 

Tim McCreight's book "the Complete Metalsmith" is a really useful book.

 

Horace and Nicolaa, thank you for the article and supplementary information

posted here.

 

Gwyneth Banfhidhleir

Ohio/Kentucky Regional MoA

Midrealm

 

 

From: branwen at ossi.com (Karen Williams)

Newsgroups: rec.org.sca

Subject: Re: Pewter Casting article...

Date: 8 Jul 1994 15:24:05 -0700

Organization: Fujitsu America, Inc.

 

sclark at epas.utoronto.ca (Susan Carroll-Clark) writes:

 

>A note on pewter:  Pewter sold today in craft stores for

>jewellery-making is usually lead free;  it is an alloy of copper, tin,

>and antimony.  A number of companies also sell pewter for miniature

>casting;  this may not be lead-free.  If in doubt, ask.  

 

You can also get pewter in hardware stores.

 

>Step 1:  The Mold

>Soapstone is the best material for pewter casting. Molds made of

>soapstone rarely break down even after a hundred or more castings;

>the molds retain heat quite well, which makes for good, clean casts;

>and soapstone can also be carved quite finely and is very simple to

>work.  If multiple castings are not needed and you have no source for

>soapstone, plaster molds may also be used.  Soapstone can be obtained

>from lapidary craft stores;  if you are having problems finding a

>source, check with your local mineral club or art school.

 

Another way to make a mold, particularly if you want to copy something

you already have, is to buy molding compound from a hobby store. This

comes in two parts, the compound and the catalyst. You make a frame

(a four-sided "fence") out of cardboard, set it on a firm surface, and

fill it about half-way up with PlayDoh (don't use white; the chemicals

to color it will mess up your compound). Put your object (your button,

your site token carved out of children's modelling clay that hardens

in the oven, etc.), in the PlayDoh so that half of it sticks out, and

pour the prepared molding compound into the frame, so that it covers the

object about two inches deep. Let it harden overnight, then flip the frame

over, take out the PlayDoh, put Vaseline on the half that's done, and pour

in more molding compound.

 

I've obviously left out lots of steps, like how to prepare the molding

compound (but that should be covered in the directions of the kind that

you buy), and the brand name of the modelling clay I'm talking about (you'll

know it when you see it in a craft store). I like this approach as it

usually takes me several tries to get the sculpting right, and it's very

easy for a beginner to do.

 

Branwen ferch Emrys  

The Mists, The West

 

 

From: corliss at hal.PHysics.wayne.EDU (David J. Corliss)

Newsgroups: rec.org.sca

Subject: Pewter casting

Date: 7 Jul 1994 10:03:43 -0400

Organization: the internet

 

Sean McAy observes:

 

> (Pewter) has a low mwlting point, which makes using paper molds

> theoretically possible (papers burning point is higher than pewters

> melting point).

 

Two things must be remembered here: first: you need to heat metal well above

the melting point if you are going to cast with it or it will begin to freeze

the moment it is removed from the heat, _before_ it fills the mold. (Yes, I

know you can heat the mold. I simply wish to point out that that it would be

best to raise the temperature well above the melting point rather than try to

avoid losing any heat.)

 

Also, it should be observed that paper is basicly just high-powered sugar. As

such, it is highly subject to _dessication_: if you bring it into contact with

any strong dessicating agent, be it chemical (e.g., highly concentrated

sulfuric acid) or physical, such as high heat, the water in the sugar will be

taken away, leaving only ash. Even if a paper mold did not catch fire, it would

still turn to ash.

 

           ....this has been a public service message from the Middle Kingdom College of Sciences.....

 

 

From: lazurus106 at aol.com (Lazurus106)

Newsgroups: rec.org.sca

Subject: Re: Pewter casting

Date: 10 Jul 1994 23:33:01 -0400

 

corliss at hal.PHysics.wayne.EDU (David J. Corliss) writes:

casting pewter will turn paper mold into ash.

Wrong kemosabee.   I use index cardstock regularly to cast pewter nose

pieces for muzzel loaders it scorches a might but it provides excellent service.

 

 

More on Pewter Casting

 

by Niccola Sebastiani

---------------------------------------------------------------------------

There is an authentic solution for how to hold the pieces of a stone mold

together when casting and make sure that the sides are aligned every time.

Using this technology also makes the three-piece molds you need to make

brooches with pins just about as easy as two-piece molds, and makes casting

really fast. Here goes (and I hope I can explain this clearly):

 

You are going to make metal locating pins that come out of one piece of

stone and fit into depressions in the other. When you have prepared your

stones so they fit together cleanly, mark a couple of places on the stone

that you intend to do the most intricate work on - the "front" of your

piece (if there is no front, it doesn't make any difference which one you

drill first). Then remove some material to make the depressions. I use a

cutter (in a drill) that makes a sort of rounded cone-shaped hole about a

quarter-inch across and three-eighths or a quarter-inch deep. These holes

should be a quarter inch in from the edge, give or take. Then mark the

spots on the other piece of stone that will be pressed against these holes.

Using a drill slightly smaller than the hole you made for the female part

of this "lock". Drill from the face of the second piece of stone about

halfway through the stone. Then turn the stone and drill from the nearest

edge straight into the stone to meet the hole you just drilled, forming an

L-shaped hole. Go back to the fist pice and cut a thin line from the edge

of the hole to the nearest edge of the stone (this is to give the air in

the hole someplace to go when you pour your pins).

 

Now line the two halves of the mold up carefully. Rubber band them

together. (This is the last time you will have to rubber band or clamp

them.) Melt some lead in your usual pot for melting the pewter. [(Please

take all reasonable precautions here - ventilate, keep your melt time as

short as possible, clean out your ladle after you finish with the lead,

keep the lead separate from the pewter - it's shiny and pretty too when

it's newly poured.) You can probably buy lead as fishing sinkers, if

nothing else. You are using lead to make your pins because its melting

temperature is higher than that of pewter, and you want your pins to stand

up, no matter how hot your mold gets.] Holding the mold in a protected

hand, pour molten lead into the holes on the side of the mold. When you

take the rubber band off, you should have rounded pins sticking out of the

back of your mold that fit directly into the depressions in the front.

 

Using these pins to align the parts of the mold makes pouring very simple

and quick. I wear an insulated glove (bought at a welding shop) on the hand

I hold the mold in and a lighter glove on the hand I handle the ladle with.

You pour, set the ladle down, open the mold with both hands (holding it

fairly close to the table surface, if you want to preserve its life), tip

the casting out, close the mold, and pick up the ladle again. I can pour by

myself at a rate of a casting every ten seconds (in the short run) once the

mold is hot.

 

I apologize if this explanation is not clear. If you will look at almost

any mold that is depicted in an archeological book (the London Dress

Accessories book shows a mold, as does the Salisbury Museum catalog of

pilgrim signs) you will see the pins, the depressions or the place where

the pins have broken out. Breaking is not, incidentally, a thing I have had

any problem with.

 

Here is one other tip, I just thought of in describing the casting. Once

you have poured the metal into the mold, it freezes first in the mold, then

gradually freezes up through the button. If, instead of standing there

waiting for the button to freeze, you pour resolutely, filling up your

mold, then tip the metal from the button back into the pot or ladle while

it is still hot you will: keep the mold cooler longer, save fuel to remelt

the button, cast more quickly, and (depending on the mold) save

considerable time in clean up.

---------------------------------------------------------------------------

I would be awfully glad to see (and own examples of) the casting done by

other SCAjuns. I will gladly trade my pieces for yours. Please contact me

at:

 

Marianne Hansen, Proprietrix

21-B E. Circular Ave.

Paoli, PA 19301

610-407-0266

billy at billyandcharlie.com.  

http://www.billyandcharlie.com.

[This address and email info has been updated - Stefan 6/24/02]

 

 

From: jhrisoulas at aol.com (JHrisoulas)

Newsgroups: rec.org.sca

Subject: Documentation

Date: 5 Apr 1995 16:04:15 -0400

 

As for documentation try "From Viking to Crusader" they have mention of

both soapstone and clay moulds found in various grave sites throughout

Europe.

 

It's ISBN is0-8478-1625-7, by Roesdahl and Wilson, Rizzoli, NY 1992..

 

Hope that this helps.

 

Your servant,

Atar Bakhtar

mka

Dr. J.P. Hrisoulas

 

 

From: sniderm at mcmail2.cis.McMaster.CA (Mike Snider)

Newsgroups: rec.org.sca

Subject: Re: Documentation

Date: 8 Apr 1995 11:16:49 -0400

Organization: McMaster University, Hamilton, Ontario, Canada.

 

Greetings,

  I have made a number of stone molds for casting buttons and pilgrim tokens.

If she has the Museum of London Dress Accessories book, that is a great

source but she may want to track down the following.

Pilgrim Souvenirs and Secular Badges By Brian Spencer ISBN 0 947535 128

 

Medieval Pilgrim and Secular Badges by Michael Mitchiner

 

I would recomment entering in the dress acc. category rather than as a

metal working entry if the criteria where you are is anything like it is

here in the Middle Kingdom. I am currently working on criteria for stone

casting, but it won't be in use for a while.

 

  If she has any sources to share or needs any help, please have contact

me directly by E-mail. I would love to hear from fellow casters.

 

Elizabeth Cadfan

 

 

From: cmhelm at artsci.wustl.EDU (Catherine Marie Helm)

Newsgroups: rec.org.sca

Subject: Re: Documentation

Date: 8 Apr 1995 21:17:40 -0400

Organization: College of Arts and Sciences -- Washington University, St. Louis, Missouri, USA

 

I missed the discussion on stone molds - dissertation do that

to a person's spare time.  I have one good reference, though the

book is damned rare:

 

p.16, figs 12 and 13

Sericite molds for casting silver pendants

12th Century, photos and discussion on molds

from the Kiev State Museum,

in: Russion Applied Art of the 10th-13th Centuries

B. A. Rybakov

Aurora Art Publishers, Leningrad, 1971

 

also see p. 123 of Dress Accessories.

Authors Egan and Pritchard

Her Majesty's Stationery Office, London, 1991

This is a brief discussion of molds but no

pictures (though the multipice ceramic mold

on p.122 is fascinating!).

 

hope this is a help

ttfn,

Twcs

 

 

From: wmclean290 at aol.com (WMclean290)

Newsgroups: rec.org.sca

Subject: Re: If not buttonholes, then what?

Date: 18 Dec 1995 16:58:39 -0500

Organization: America Online, Inc. (1-800-827-6364)

 

In article <francis-1712952227450001 at tigana.microserve.com>,

francis at tigana.microserve.com (John [Francis] Stracke) writes:

 

>Also, what sort of buttons are acceptable? I'm pretty sure little white

>balls are OK, but they're kind of boring.  :-)

 

Yes, buttonholes are period for the 14th c.. Cloth and cloth covered

buttons are well documented for the same period., in the same fabric as

the garment.  The modern kits for cloth covered buttons are an easy way to

get the right general effect, although for maximum authenticity you can

make them yourself. "Medieval Finds from Excavations in London. Vol. 4:

Textiles and Clothing", Crowfoot et al, has really good info.

 

Vol. 3 from the same series, "Dress Accessories", Egan and Pritchard, has

metal buttons from the same period, usually cast and always made with

shanks (as opposed to being pierced with holes like a modern shirt button.

 

Marianne Hansen casts intensely cool reproductions of several of those buttons in pewter from handmade soapstone molds. She also makes buckles, fittings, belt mounts, badges, pins and spoons. Neat stuff!

 

[Contact info is:

Marianne Hansen, Proprietrix

21-B E. Circular Ave.

Paoli, PA 19301

610-407-0266

billy at billyandcharlie.com.  

http://www.billyandcharlie.com.

This address and email info has been updated - Stefan 6/24/02]

 

 

One interesting detail: On all of the London finds the buttons are sewn to

the very edge of the garment, rather than set slightly back from the edge

as in modern garments. You can see the same detail in many paintings from

the 14th and 15th c. if you look closely.

 

Will McLean/Galleron de Cressy

 

 

From: sjaqua at ix.netcom.com(Scott Jaqua )

Newsgroups: rec.org.sca

Subject: Re: Casting with soapstone molds

Date: 21 Jun 1996 14:08:05 GMT

 

Dennis Loyer <dloyer at earthlink.net> writes:

> Try requesting a catalog from TSI (800) 426-9984, They carry lead-free

> pewter in wire, sheet, and nuggets (for casting). They also

>carry just

>about every jewlery and casting tool, book, or supplies you may ever

>need. They also carry gold, silver, and copper in the same forms as their

>pewter, as well as precious stones and beads.  Need a centrigigal casting

>machine for lost wax casting? They got it, and their prices are fairly

>reasonable.  

 

    Don't forget they would carry a vacuum caster as well. Having used

a centrifugal caster when a flask fails and have it sling molten bronze

about, I MUCH prefer my vacuum caster. Matter of fact, anybody

interested in the old centrifugal caster?

    Allesaundra de Crosthwaite

    mka Sandra Jaqua

 

 

From: Andrew Lowry <alowry at wchat.on.ca>

From: Mike Snider <sniderm at mcmail.CIS.McMaster.CA>

To: Mark Harris

Date: Wed, 26 Jun 1996 00:52:45 -0400 (EDT)

Subject: Re: pewter casting

 

Greetings,

  Mistress Nicolaa is quite correct in telling you that the practice of

casting pewter in stone moulds is Medieval, but it actually predates Sca

period by quite a while as well. The Norse used this technique to great

effect, but the trade in buttons and pilgrims badges peaked in the

1200-1500s. I have had the opportunity to handle a great many medieval

badges and moulds during my travels in Europe, but unfortunatly such

articles are scarce or absent from North American museum collections.

There are, however, several good books on the subject available. If you

send me your address I can mail you a copy of Getting Started in Stone

Casting which has examples of period techniques for casting,

illustrations of extant peices and a bibliography of source books. As you

are an experienced metalworker, some of the information may be stuff you

already know, but it might be worth it for the pictures.

 

  If I can be of any further help about sources, techniques etc.. please

feel free to contact me directly. I read my mail fairly regularly. If you

are going to War, I will be merchanting and doing some pouring in my

booth. Drop by with your moulds. I always enjoy talking shop.

 

Your servant,

Mistress Elizabeth Cadfan

(Kes)

 

 

From: Mike Snider (6/26/96)

To: Mark Harris

RE>pewter casting

 

Greetings,

  I will put the booklet in the mail today. I live in Hamilton, Canada,

so it may take more than a week to get to you. Don't worry about the

expense, it is just a small booklet to get people started.

 

  I hope you can make it to War. I am not sure if I was the person you

spoke to. There are two of us working at this scale in this field. One is

Mistress Nicola from the East (not De Bracton) who is a large short woman

with dark hair. I sell under the name Fettered Cock Pewters and Wife of

Bath Giftwear both. I am petit, very blond and usually sunburnt at Pennsic.

Do drop by the shop if you can. I will be bringing quite a number of

moulds to War which you may enjoy pouring to see how they work.

 

   Is the melting pot you have for bullets? I tried them and found it

hard to get hot enough for many of my moulds. I have cast over a camp

fire, but again, it was hard to keep the heat up. Charcol was what they

used in period, but it is expensive and not environmentally friendly for

a city dweller like me. I use an iron ladle over a propane burner and

this works really well and is very portable. Have a local smith or

armourer make you up a ladle or try the flea markets. you may get lucky.

 

  Stone is always a hassle to find. Try to find stone without too many

inclusions (the hard nobs) by spitting on the stone. The moisture will

make it easier to see imperfections in the stone. I cut my blocks with a

hacksaw. It is labour intensive, but it does work.

 

Ta for now,

  Kes

 

 

From: irgenwer at ix.netcom.com (Kate was here)

Newsgroups: rec.org.sca

Subject: Re: Soapstone Casting  (LONG)

Date: Tue, 04 Feb 1997 11:27:14 GMT

Organization: Quahaug Cannery

 

>I'm fairly sure that a well dried/baked stone mould will handle

>silver in small size castings.  My question is how many repeat

>casts one can get out of a stone mold with silver before the

>mold starts to break down?  We're talking a 1100 to 1200

>degree F temperature difference between the white metal alloys and

>sterling. Has anyone out there tried it? -- al Thaalibi

 

The massive talc I've used has cracked every time I've tried

casting with metals whose melting points are above 1000 C.

However, the molds I've made out of a very nice red-brown

sericitic schist from Michigan have held up every time. I've

cast silver, sterling, and various bronze alloys in this stuff

very successfully.  I've not broken any mold bases yet, but

I've gone through a lot of keys on the two-piece molds I've

made.  I've only broken one key on the three piece molds I've

made.  The largest amount of silver I've done in a stone mold

is one ounce.  My bronze pieces are about the same size.

 

I have no idea how many castings you can get with the higher

melting temperature metals and alloys.  I need to break a mold

base first, and then I'll have an idea.

 

Casting metals which melt above 1000 C require a very hot

mold (not unlike investment molds)- which is not the case

with pewter, where you can pour into a relatively cool mold.  

Actually, I would opine that heating the mold is much more

imparative that for investment casting - especially for the

first few castiing.  Let me explain: "soapstones" are mostly

phyllosilicates - minerals which grow in layer cake-like

structures, with tightly bonded layers of SiO4, oxygens and

OH, and a frosting between these layers of large cations

like potassium.  The large cations take up a lot of space

between the Si/O/OH layers - so much so that there's

room to stuff a lot water molecules into that gap.

 

Phyllosilicates  dehydrate when subjected to sufficient

heats.  I've knew this theoretically, but it never really sunk

in until the first time I cast bronze in a stone mold - the

mold blew up with a small cloud of steam, and molten bronze

sprayed across the room.  My guesstimate for mold temperature

was approximately 500 C - obviously not hot enough.  I took

the pieces of the dead mold and examined the path of the hot

metal through it.  What I fould was an anhydrous silicate mineral

coating the entire  pathway.   The anhydrous silicates are tough

and melt at very high temperature - which means that the passage

of the hot metal created a hard and resistant lining inside the mold.

 

These days, I heat my molds to approximately 1000 C prior

to pouring, and I've not lost a mold since.  Really cook your mold,

and dress as if you know that the mold will self-destruct and

spray metal.  The dehydration of soapstone is a given, but if

you really roast that mold, you can drive off a lot of the water

trapped in the rock before it sees any hot metal.

 

>djheydt at uclink.berkeley.edu (Dorothy J Heydt) wrote:

>| Just keep in mind if you do, soapstone is solid talcum powder and

>| can muck up your lungs if you allow it to get into them.  Wear a

>| filter mask while working it.  

 

I would say, conversely, that talcum powder is ground up talc, but

here I'm probably picking nits  ;-)   What is sold as soapstone in

the US is one of four different rocks: massive talc, massive sericite,

talc +/- sericite schist and NON-abestoid serpentine.  Art store

people in general are not well-educated about the mineral content

of the soapstones they sell.  I've had people at one of the local

art stores hand me serpentinite and tell me it was sericite.  *sigh*

 

You can work the soapstones WET.  I've seen some people carve

it in a large bowl of water.  I personally prefer to carve it

dampened with a wet cloth (which you also use to wipe off the wet

clay-like scrapings as you work).  If you don't work with rocks

every day like I do, the exposure risk is extremely small, even

if you carve it dry without a mask.  

 

The truth of the matter is that if you've not been fitted to a

half or whole face respirator, then no mask you wear will give

you assured protection.  It's a basic tenet of respiration safety

that unless you've been personally fitted to a respirator and have

subsequently passed a fit test, then you must assume that the

respirator leaks.  Consider also that you make rock dust while

dry carving - but unless you're working in a hood or a dust box,

you're going to get rock dust in your clothes.  That rock dust

will follow you home, where you can breath it long after your

carving is finished, and long after when you put your respirator

away.  The whole bit about a mask is kinda silly since it doesn't

solve the problem of  making dust - it might prevent you from

inhaling some dust while you work, but it's not going to prevent

you from taking some dust home with you when you're done rock

carving.  Not making dust in the first place is the preferred

thing to do - and  carving wet does this for you.

 

The principle danger of working with silicates is the dust.

It's worth mentioning that where I work, every rock saw,

grinder, polisher and coring drill is set up to operate wet.

 

david.razler at worldnet.att.net (David M. Razler) posted:

>Adding to an excellent remark, "talcum" is another way of saying "contains

>asbestos-like fibers" (please use cornstarch powder on the young ones. It is

>not period, but it also makes for a better gravey when you cook them)

 

I'd like my kid broiled, with potatoes on the side   ;-)

 

I'm afraid I must differ: talc is not one of the asbestos

minerals.  It breaks up into little platelets - it does not

form fibers.   No fibrous habit, no asbestos.  Mind you,

I'm defining asbestos as a certain set of minerals with

fibrous habit and refractory character.  This is a mineralogical

definition - it is not the same as US-OSHA's definition, which

is presumably based on occupational health criteria.  What

I call asbestos is actually much stricter than what OSHA

calls asbestos.  As a mineralogist, I'd define the two asbestos

minerals as chrysotile serpentine and tremolite.  They don't

carve well if they carve at all.  It would  be like carving

petrified fossilized linen.

 

The dust hazard is real, regardless of the fact that the

soapstones are non-fibrous.  You won't get asbestosis from

them, but you can get silicosis and stomach cancer with

prolonged use.  (Back before California turned into a rice

growing area, rice was shipped by boat from asia.  Many

housewives in China Town in San Francisco would buy the

rice and take it home.  There they would wash it, and then

feed it to their families.  It was a mystery at the time

as to why women from China Town had a much higher rate

of stomach cancer with respect to the rest of the city,

Then someone discovered talc in the rice bags.  In order

to ship the rice, the folks on the other side of the Pacific

would throw in a handful of powdered talc as a

dehydrating agent.  Since china town housewives were

the only people to handle the unwashed rice, they got all

the talc exposure.

 

Asbestos, by the way, is defined by the US gov't to be

any rock fiber with specific dimensions  (which I don't

remember off the top of my head).  The gov't doesn't

use the mineralogical definition at all.  The definition

is soley based on size.  IMHO, this is really stupid.

An USGS employee showed almost 20 years ago that

the asbetos which caused most cases of asbestosis

was the tremolite variety.  In addition, most of the

non-mining asbestosis cases were from shipyards!

Alternatively, I have never heard of any artists who

died of silicosis from carving soapstone (if anyone

does know of such a case, please correct! me  ;)

 

ttfn, Twcs

 

 

From: j_mohler at wmc34b.wmc.edu (Jason)

Newsgroups: rec.org.sca

Subject: Re: medieval candles--??

Date: 6 Feb 1997 06:50:50 GMT

Organization: Western Montana College, Dillon MT

 

markh at risc.sps.mot.com (Mark S. Harris) writes:

>I'm afraid he is not that far off. I guess it depends upon the vender.

>I'm currently paying $0.50 or $1.00 per pound for the lowest of three

>grades of soapstone here in Austin from the only Lapidary/rock shop

>that has this stone in Austin, TX. And the last chunk I got had a lot

>more oclusions and large particles than the stuff I got previously.

>

>Now where did you say this talc mine was? :-)

 

Ten miles south of Dillon, MT.  But if thats too far, theres also one in

Three Forks, MT. :)  Another idea might be ardulite(sp?). Its a sedimentary

rock that is as easy to work with as soapstone.  Around here it was used alot

it ceremonial pipes.  Its basically a clay, so it hardens when heated.  The

only thing is, I'm not sure how hard it is to get in the rest of the world,

as (I think) it requires the presence of glacial lakes (any geologists/

minerologist help me on this?), which were plentiful in the northern Rockies,

but a little lacking in Texas.

 

Erik Blackwood

=======================================================================

Jason Mohler                            "Could you please continue the

j_mohler at wmc34b.wmc.edu                 petty bickering? I find it most

http://www.geocities.com/Athens/4162/   intriguing." -Data

 

 

From: irgenwer at ix.netcom.COM (Irgenwer Schuld)

Newsgroups: rec.org.sca

Subject: Soapstone Casting (WAY-LONG!!!)

Date: 6 Feb 1997 02:32:15 -0500

 

>Greetings unto Twcs!

>>Long time no hear from! I wasn't sure you were still frequenting the

>Rialto. Got a well used soapbox around here, somewhere.

 

Hi Stefan:

This is the first time in a long while that I've had a little time

to spare for lurking on the bridge.  I guarentee that I'll be gone

again for several months in just a few weeks.  I'm on the home

stretch for finishing my dissertation research, and it manages to

eat up time very effectively!  I'm also spending most of my time

"allowance" for SCA activities on running the local fighter practice

(in pursuit of my life-long ambition to become a stickjock!)

 

I'm crossposting this to the rialto, since you brought up a question

that more than one person may be interested in.  Here goes:

 

>This is the first time I've heard of carving saopstone wet. No one

>suggested it here in previous discussions. In fact, some cautioned

>against getting the stone wet, because the water wood boil off and

>crack the stone similar to what you describe, even at pewter

>temperatures.  I wonder if I could bake my mold in the oven after

>carving it wet to dry it out? Perhaps nearer the boiling point of

>water than the 500 degrees of the pewter?

 

You basically have the right idea!  I bake out my molds, first to

drive off the residual non-stoichiometric water from carving it

wet, and then to get it up to a temperature where I no loinger worry

about any sudden dehydration reactions from the hydrous silcates

present in modern soapstones.

 

Well - hit me over the head with a wet noodle!  Shame on me for not be

sufficiently detailed.  I watch the sculpture class in the room next

door to where I do most of my casting - and they're all carving their

soapstone under water in bowls and tubes, or with wetting it down with

a wet towel.  I'm under the impression from talking to the sculpture

types, that this is becoming more and more common as artists get better

educated regarding the materials they use.  But with regards to carving

your mold wet and then using it for casting, I need to get the

noodle squad over to do their thing to me, for I now realize that I

assumed everyone knew about how to properly bake a rock and why!

 

I mean - just think about this for a second - here I am, sitting around

and assuming that, of course, people bake their own rocks every day,

all the time!  Why, I think nothing of popping a rock into the furnace

and cranking up the heat!  YOU THINK I'M KIDDING?!?!?!?!?!?!?  I'm not!

 

But let me explain: I torture rocks for a living.  I'm a professional

mineral nerd.  At this point, I probably have rocks in my head, as well

as in my lab, my office, my truck, my closet, my bookcase (well, the

nice-looking ones...).  I don't think anything of just popping a rock

into the oven, if that's the appropriate thing to do!

 

So let me tell you in greater detail about how to bake a rock.

 

First, don't do it with massive talc.  There's a really lovely

pale green massive talc currently on the market in the States and

Canada that I see a lot of SCA folks east of the Rockies using for

their pewter casting.  But it has really serious problems with

cracking while being worked.  If you put massive talc in the oven,

it's going to break!  That's the nature of the mineral.

 

If you want to use a "soapstone" (please see my previous post for

the definition of this), use one of the schists on the market.  A

phyllosilicate-rich schist that's nice enough to be used as a

soapstone has enough other stuff in it to keep it together while you

abuse it.  The lovely brown-red schist from Michigan is a real winner

in this regard (give me a few days and I'll probably be able to hunt

down the quarry name); there's also a delightful sillimanite schist

from the Ruby Mnts in Nevada that would do well for the casting

application too.  The talc schist from south of Mariposa in the south

Sierra Nevada doesn't work (I tried) - it's not fine grained enough.

 

So the first thing you need to do is pick the right rock to bake.

Use a schist and not a one-mineral "soapstone" like sericite or

massive talc.

 

The second thing to do is carve it.  Now, regardless of the actual

identity of the rock you're using, if it cracks while you're carving

it, it'll crack in the oven too. Rock that will crack with just little

abuse will not last through high temperature casting.

 

Now let's assume the mold is carved.  For the sake of discussion,

I'll use a three piece mold as an example.  For pewter casting, the

period practice (and current state of the art in SCA nations east of

the Rockies) was to pour lead pins through the mold pieces to keep

it aligned while pouring the pewter.  If you're aren't familiar with

this, there are some really helpful pewter-mavins who have properly

constructed period molds and cast with them in the shopping district

at Pennsic. One of them (a laurel from Ealdemere, I believe) has a

very nice pamphlet with drawings and such - I'd go and check it out

there, since you're much closer to Pennsic than I!

 

Anyway, about pins: you'll need them.  Melted bronze is too damn hot

to pour without pins.  (If it hadn't been for the pins I had put in

my very first stone mold - the one that blew up from explosive dehy-

dration of hydrous silicate minerals - I and my casting buddy may

have ended up injured badly instead of merely embarrassed.)  Now, I've

not come up with anything elegant, like the lead pins in a pewter

mold, but my current solution works well enough for me.  I use bronze

machine screws and fittings - marine hardware quality bronze, in fact.

Why?  Well, first, pouring bronze in a mold held together with bronze

isn't going to melt the screws and nuts.  And marine bronze can

tolerate thermal expansion and contraction a lot better than most

steel hardware.  Last, I lifted my marine bronze machine screws,

washers and nuts off my Dad's hoard of boat hardware so it didn't cost

me anything.  The bronze screws work well with melted silver too (I've

poured silver twice now into one of my stone molds)

 

To put them into the mold, I drilled with my low-speed

dremel a hole just slightly smaller than the diameter of the

screw-threads.  Then I carefully hand=threaded the screws into the

rock. I like a four screw arrangement best.  Two screws through the

key pieces, and a screw apiece through each key piece into the base.

I do attach a nut to each

threaded screw - the thought of an uncontained steam-and-hot-metal

explosion while casting in a new mold is not a happy one. Actually

bolting the fool thing together will keep any inadvertant explosion

contained mostly within the mold itself.  For metals above 1000 C,

I'm not going to trust just pins.  A burn from pouring pewter can

be really really nasty - but a burn from melted bronze could ruin

the rest of your life.  Bolt the mold together.

 

Now, after actually bolting the mold together, I retract the screws

just a little bit, so there's a small air gap between the key pieces

and the base.  With all the hardware attached, and with small airgaps

between pieces, I put my new mold into my home oven, at 200 F (note

the temperature scale change here!  It's important) overnight.  If it

lives, I crank up the temperature to 300 F the next night, and then to

400 F.  If it lives (the massive talc dies before I ever get it out

of the house, the schist survives), then I take it into the craft

center on campus and put it in one of the casting kilns - to bake at

500 C (temp scale just changed back to celsius!) overnight or until

I'm ready to cast - whichever is longer.  When I'm ready to cast,

that morning I will turn up the heat so the mold will be approx 1000 C

when I have my metal melted and ready to pour.  I'm estimating the

1000 C based on the color of the fire bricks on the inside of the

kiln I like best at the craft center. (After you play with melting

rocks and metals, you get a feel for temp in a furnace based on color,

instead of having to dig out the thermocouple and poking it through

the hole on top of the furnace)

 

This is my current procedure.  It might be overkill, but the exploding

dehydrating schist made a deep impression on me the first and only

time I had a mold explode on me.  And any phyllosilcate

that's been cooked a while at 1000 C is going to suffer surface

dehydration reactions and metamorphose into its anhydrous pyroxene

equivalent (in general - any rockknockers who want to pit nicks, can

do through email...).  And the way to get any rock hot (not just a

phyllosilicate-rich one) is to do it gradually.  Baking a rock too fast

is like microwaving cold out-of-a-can raviolli on high: it go BOOM and

make a mess!

 

So, to sum up in just a few words: don't use massive talc, bring your

mold up to temperature in steps gradually, and make sure your mold

achieves 1000 C before casting.   And if you're not wearing a foundry

mask, hood, sleeves, mitts and attached apron (and equiv on your legs

and feet), you're going to get hurt.  This is real pyrometallugy here;

dress appropriately.  Paranoia is a good thing to have around the

melted "first-row" metals.

 

Oh, and one last thing: this isn't investment casting - so don't

throw the mold into a bucket of water to cool it down.  Do that and

it will explode if it's still hot.   I've seen rocks explode from

thermal stress - it's not a pretty sight, especially when you've seen

the injuries that people can get from flying hot-rock shrapnel.

 

What did they do in period? (I can hear someone ask!) Well, thus far

I've been able to document repeat-use molds for high-temp casting made

out of fired-clay (one mold with many pieces!, for casting multiple

bronze buckles at one shot), sericitic schist for silver jewellry

pieces, calcareous sandstone (again for bronze) and fine-grained

limestone (bronze).

 

There.  That's all you're going to get out of me this evening!

And now it's back to procrastinating cleaning my kitchen...

ttfn, Twcs

 

 

From: james koch <alchem at en.com>

Newsgroups: rec.org.sca

Subject: Re: Brass Works

Date: Sat, 03 May 1997 17:36:51 -0400

Organization: alchem inc

 

Tiernan001 wrote:

> I was looking for some help with some Casting and Etching that I need to

> do for some decoration of my armor.  I am especially interested in peroid

> casting ( i.e. Lost Wax Casting and the like) and etching in general.  I

> am fairly familiar with Lost wax casting up until the point of what one

> does with the wax and the Silica sand to make a mold. I'm not to familiar

> with the actual melting of the Brass (i.e what tempratures, equipment for

> safe casting, ect...)  As far as Etching is concerned, I have etched Zinc

> plate (for a Printmaking class) before, and was more interested in a

> possible source for supplies (I have no clue as to where to buy acid, and

> I forgot what chemical(s) the resistor was).  I am probably biting off way

> more than I can chew, but.....   OH WELL!

>

> Tiernan Diego of the Waters

> E-Mail at : Tiernan001 at aol.com

 

Mr. Diego,  There are a number of materials from which you can make

molds.  You can carve and cast directly in soapstone, refractory brick

(the stuff used to line kilns), or graphite.  You can make an original

and press it into foundry sand (fine sand with powdered dry clay added),

dental plaster, or clay.  The plaster and clay must be thoroughly fired

to remove all traces of water prior to pouring the metal!!!  Otherwise

the mold will explode spewing molten brass.  

      Commercial crucibles are available from various sources.  In a

pinch you can melt brass in a piece of black iron pipe screwed into a

cast iron pipe cap.  An enamelling or ceramic kiln will provide

sufficient heat if you plug the vent holes.  

      For safety's sake buy a bag of play sand and nail 2 x 2s to a

piece of plywood to make a sandbox.  Molten metal can be poured on

sand.  Do not pour or spill molten brass on concrete since the cement

contains water of hydration!!!  More flying molten brass.

      Sulfuric and hydrochloric acids can be purchased by the quart or

gallon at most hardware stores.  These are sold as Organic Digestor in

the plumbing section and as Muriatic Acid in the paint section.  Mix the

Sulfuric Acid with Sodium Nitrate which is sold as Nitrate Of Soda

Fertilizer in the gardening section.  From this mixture you can distill

off Nitric Acid.  The Nitric Acid can be used to compound Aqua Regia for

etching.

      Also, before I forget, always melt brass in a well ventilated

area.  I used to melt indoors and would come down with Zinc fume fever

afterwards.  When brass melts the Zinc boils off and ignites producing a

blue white flame over the crucible.  The resulting Zinc Oxide smoke when

breathed forms soluble Zinc Hydroxide in the lungs.  This is absorbed

into the bloodstream where it disrupts your body's temperature control

and you go from the violent shaking chills to the sweats and back again

for several hours.  Fortunately Zinc occurs in the body naturally and

the kidneys rapidly excrete the excess.

      Good luck and have fun!  Gladius

 

 

From: Corbie <corbie at no-spam.radix.net>

Newsgroups: rec.org.sca

Subject: Re: Brass Works

Date: Sun, 04 May 1997 19:04:52 -0700

 

> tiernan001 at aol.com (Tiernan001) wrote:

> > I was looking for some help with some Casting and Etching that I need to

> > do for some decoration of my armor.  I am especially interested in peroid

> > casting ( i.e. Lost Wax Casting and the like) and etching in general.

(snip)

> > Tiernan Diego of the Waters

> > E-Mail at : Tiernan001 at aol.com

 

My husband and I have both done bronze sand-casting, which has a more

time-consuming finishing process than lost-wax bronze casting, but has

the advantage that you can make multiple copies of the object in

question, and making the original mold is rather easy. The class was

taught by the boatbuilding school associated with the Alexandria Seaport

Foundation (Alexandria, VA) with an eye toward people making things like

boat cleats and so on.  I don't know if you're in reasonable vicinity to

the DC area, but it's a good class.  The man who taught it does castings

of gun parts for reproductions of American Revolution-era guns, and his

work is museum-quality.

 

To make the original of what you want to cast, you make a wooden pattern

(making sure the angles (drag) are proper for sand-casting, of course);

then you tamp the sand up in the molds, etc. etc. (ramming the cope)

You can re-use the wooden mold as many times as you like. The process

has a few more steps than this, of course, but it wasn't too difficult.

 

Mara/Corbie

 

 

From: afn03234 at freenet2.afn.org (Ronald L. Charlotte)

Newsgroups: rec.org.sca

Subject: Re: Brass Works

Date: 7 May 1997 04:38:15 GMT

 

tiernan001 at aol.com (Tiernan001) wrote:

> I was looking for some help with some Casting and Etching that I need to

> do for some decoration of my armor.  I am especially interested in peroid

> casting ( i.e. Lost Wax Casting and the like) and etching in general.  I

> am fairly familiar with Lost wax casting up until the point of what one

> does with the wax and the Silica sand to make a mold. I'm not to familiar

> with the actual melting of the Brass (i.e what tempratures, equipment for

> safe casting, ect...)  As far as Etching is concerned, I have etched Zinc

> plate (for a Printmaking class) before, and was more interested in a

> possible source for supplies (I have no clue as to where to buy acid, and

> I forgot what chemical(s) the resistor was).  I am probably biting off way

> more than I can chew, but.....   OH WELL!

 

The best basic guide I can reccomend are _The Complete Metalsmith_ (ISBN

0-87192-240-1) and _Practical Casting_ (ISBN 0-9615984-5-X) both by Tim

McCreight.  They have all of the basic info on casting and other non-

ferrous metal work, including etching and patinization, with all of the

temperatures and formulas.  They're written very readably without

burying a beginner in technical terms.

 

For historical techniques; there's _De Re Metallica_ by Georgius

Agricola (ISBN0-486-60006-8), _The Pirotechnia_ by Vannoccio Biringuccio

(ISBN 0-486-26134-4) and the classic _On Divers Arts_ by Theophilus

(ISBN 0-486-23784-2).

 

All five books are available for under $US 20.00 each, and are currently

in print.  The last three are Dover reprints of historical treatises,

and are quite inexpensive.

 

I hope this helps...

--

     al Thaalibi ---- An Crosaire, Trimaris

     Ron Charlotte -- Gainesville, FL

     afn03234 at afn.org

 

 

From: timbeck at ix.netcom.com

To: Mark Harris

Date: Sun, 6 Jul 1997 01:10:15 -0500 (CDT)

Subject: Re: slush casting

 

On 07/05/97 02:25:02 you wrote:

>>On toys I have seen a few examples of period dolls slush cast in

>>pewter and I have seen depictions in paintings of cloth dolls.

>

>I cast pewter medalions and coins in soapstone molds. I would be

>interested in hearing more details of this "slush" casting and

>any documentation on it's being a period technique.

---------------------snip-----------------

 

In the MOL _Dress Accessories_ Item #1396 is a hollow tin button cast in a

three-part mould. "The back has two possible blow holes along the casting

seam; shank missing; slush cast."  The item is from ceramic phase 9 giving

it a date between 1270 and 1350 ce.  The book _Pewter A celebration of the craft

1200-1700_ also from the MOL isbn0-904818-36-5 has an example of a

hollow cast doll from c1600 and a series of miniture jugs, flagons, and

ewers from the 13th to 16th century.  I also believe that this is how

ampulae were cast.

 

The process is explained by Oppi Untracht in _Metal Techiniques for Craftsmen_

isbn 0-385-03027-4.  He says that "hollow castings of pewter

can be made by pouring molton pewter into a chilled bronze mold.  After a

few secconds are allowed for the metal that makes contact with the mould

wall to freeze, the mould is inverted and the still liquid metal in the center of the mould space is poured out into a ladel or container."

 

This is a good way to make light weight castings and save on metal.  It is

apparently used by pewterers making spouts and hollow components of pewterware.  I think this method could also work with other types of

molds with large voids.  But obviously the nature of the bronze to sink the

heat would be nice.

 

Hope this helps,

 

               Timothy

 

 

Date: Tue, 11 Nov 1997 18:14:16 -0500

From: rmhowe <magnusm at ncsu.edu>

To: bryden at hers.com, cbryant at hfw.com, markh at risc.sps.mot.com

Subject: Medieval Casting Resource Books Article

 

Medieval Casting Resource Books

Copyright 1997 by R.M.Howe,

aka Master Magnus Malleus, O.L., Atlantia

 

I have been researching period metalcasting from all over

the world for some time now and have articles and books dating

from Celtic and Roman times to China, India, and Thailand.

What I am going to list now deals with some of the more

medieval sources. This is by no means all I have found, just

some of the more important - principally being Dutch later

medieval pewter badge casting, pre-Viking metalcasting using

a removable model (not lost wax) and lost wax casting in Viking

times.

 

I could write a paper on this but it would be fairly complex

and very dangerous to the average experimenter. Especially when

one casts in clay molds. I accept no responsibility whatsoever

for any injuries incurred during your experimentations. I am

only listing primary sources, not giving instructions here.

 

The history of metal working is called Metallography if you

get really interested.

 

 

For end of 5th to 9th century A.D. pre-Viking metalcasting you

will want to see two different books. The second one explains the

techniques of the molds you will see in the first one, which while

300 pages doesn't explain the technique at all well and does not

illustrate it.:

 

EXCAVATIONS AT HELGO IV - WORKSHOP part I (In English) Editor

Wilhelm Holmqvist in collaboration with _Kristina Lamm_, Agneta

Lundstrom, Jutta Waller. About 300 pages and plates. Kungl Vitterhets,

Historie Och Antikvitets Akadamien, Stockholm, Sweden by Almqvist

and Wiksells Boktryckeri AB, Uppsala 1972  ISBN 91-7192-033-1

 

This contains an overview of the huge shop area and pictures of

about a thousand or so artifacts and molds of square headed bow

relief brooches, clasp buttons, dress pins, a few buckles, a key,

glass necklace and a few odd metal pieces. It shows many

of the mold pieces and catalogs design variations.

 

You need to view the following book to understand the molding and

casting process. You will note that Kristina Lamm is again the

author of the relevant article in it:

 

BRITISH MUSEUM OCCAISIONAL PAPER NUMBER 17 'Aspects of Early

Metallurgy', edited by W.A.Oddy, British Museum Research Laboratory

1980. ISBN 0 86159 016 3. The Article relevant is: Early Medieval

Metalworking on Helgo in Central Sweden, by Kristina Lamm. Until

you see this one you really won't understand the other book.

There are very good diagrams of several types of completed piece

molds in the article, not in broken pieces as in the above book.

 

The BMOP#17 also contains a bunch of other articles on early metal

work, much of it quite sophisticated. There are among them articles

on gilding, tinning, gold and silver working (with a roman style

lathe turning a soldiers metal pan/sieve to clean it up), joining

and casting arts. A short article in it makes reference to early

Celtic British casting at Gussage All-Saints, which is another

extensive metalcasting find. They cast mostly chariot fittings

at that site, involving casting rings within bits for example. That

is not covered in it's entireity in this book. British Isles Celtic.

 

 

Lost Wax metal casting of the Viking Age is covered in English in

RIBE EXCAVATIONS 1970-76, Volume 2, edited by Mogens Bencard,

Sydjysk Universitetsforlag, Esberg, l984. This is another fairly

large book and the part you are looking for is:

METALCASTING  Techniques, Production and Workshops, by H. Brinch

Madsen. This book principally covers the lost wax process of the

Viking age and is most likely the original source for those two

page casting techniques you see in other books on the Vikings.

The technique here centers on casting the turtle or Berdal brooches

using a cloth, wax and clay molding process. It is very well illus-

trated as to the technique and the designs of the pieces themselves.

A few keys are illustrated, so are mold pieces.

 

 

Many of us have the Museum of London modern books. There was an

earlier London Museum Medieval Catalogue 1940, reprinted by Anglia

1993, 319pgs. By J.B. Ward-Perkins. It contains some information

on badges and molds, and various material later published in larger

context in the Museum of London Books. Available from Oxbow Books: U.K.

0-1865-241-249 phone number, or David Brown Book Co.: 860-945-9329.

 

 

A recent book on ANCIENT CHINESE CASTING has recently been released

in cooperation with Princeton U.. It is called Art of the Houma

Foundry and it is very replete with illustrations of the complex

molds and techniques. It is also very expensive at $175. They don't

give discounts on this one. It involves making positives and

pieced negatives in clay primarily. Fantastic art and work though.

 

 

In the event that you are interested in the casting of PEWTER BADGES

a primary book on the subject is in Dutch. (Sacred and Profane)

 

HEILIG EN PROFAAN  1000 Laat-Middeleeuwse Insignes uit de Collectie

H.J.E.Van Beuningen. H.J.E.Van Beuningen - A.M.Koldeweij

ROTTERDAM PAPERS VIII. Published by Stichting Middeleeuwse en Profane

Insignes, Brink 5, 3945 BE Cothen - Nederland. ISBN 90-9006769-8 geb.

CIP-GEGEVENS KONINKLIJKE BIBLIOTHEEK, DEN HAAG. Hb 342 pages. 1993.

Current 11/97 price from Oxbow is $105.

 

There are 1000 or so late medieval Dutch pewter badges in this book

about evenly divided between religious and secular themes. Some are

humorously obscene, some are simply poor man's jewelry, some are

heraldic tokens, some love tokens. Most of the religious ones are

broken. The casting process is very clearly depicted, unfortunately

in Dutch, and almost all the molds are made of slate.

There is a short summary section, mostly history in English.

-------

Permission is granted to use this in Stefan's Florilegium, Whistling

Arrows, or the Oak, the A&S publication of Atlantia.

 

 

Date: Wed, 14 Oct 1998 20:42:02 EDT

From: <BastetKat at aol.com>

To: sca-arts at raven.cc.ukans.edu

Subject: Re: Hot-Striking coins [SCA]

 

     What you are describing is casting, and the method your friends are using

will not be very successful. Hot-striking would be heating the metal up to an

annealing temperature (see my letter on circlets), not melted, and then put it

in the die. There is really no advantage to this over cold die casting (unless

you are working with much harder metals than bronze).

 

     There are several ways to cast metal. Similar to what your friends are

doing is charcoal block casting, where the design is carved into a block of

charcoal. The metal is place directly into the recess and hit with a torch

until melted. Then a second charcoal brick is set (not slammed, unless you

WANT molten metal in your lap) down on the first. This mold is good for 3-4

1-sided castings.

 

     Another method uses two charcoal blocks, with a front and back design,

wired together. You can get a two-sided casting, but the limitations are

considerable. As your friends have discovered, as soon as the heat source is

removed, the metal immediately begins to solidify. Therefore, only very short

or small castings can be done this way, and the opening needs to be fairly

big. It will help if you heat the mold up as hot as it can take (depends on

what it is made of).

 

     Another method is sand-casting, which will also produce a single sided

casting. The amount of detail you can get with sand casting is limited,

however.

 

     I'm pretty sure that in period coins were simply die-struck on cold

metal, as you have described. However, lost-wax casting could be used to

make multiple two-sided coins at once. If you are more concerned with mass

production over historic authenticity, than this might be the way to go.

Unfortunately, it requires some specialized equipment. If you have an Arts &

Crafts center where you live (are there any Universities?), you might want

to check them out.

 

     Basically, the process of lost wax casting (which dates back to the

Bronze ages) is this: a model is carved in wax, then a plaster mold is made

over the wax. Then, the wax is burned out of the mold. Finally, molten metal

is forced into the vacant spaces created by the burned-out wax. I repeat:

forced. It is not possible to simply pour it down the hole for the same

reasons the two-part charcoal block is limited. Usually centrifugal force is

used, or a vacuum (vacuum is inferior).

 

     I will be happy to answer any specific questions, but it will be much

easier if you can find some local person who has prior experience to stand

over your shoulder. I can describe techniques to you, but cannot show you how

to do it (like what color the metals turn as they are melting, etc.). Also, to

do it well, you'll need a lot of fairly expensive equipment.

 

Judith

 

 

Date: Fri, 23 Jan 1998 12:59:27 -0800

From: Edwin Hewitt <brogoose at pe.net>

To: sca-arts at raven.cc.ukans.edu

Subject: Re: Casting Website

 

D. Patkus wrote:

> Heads up metalworkers, people who cast and Viking

> types.  I just found a new website -> see

> Welcome to The Viking Bronze Casting Site at

>  http://user.tninet.se/~mfx106d/index.htm

>

> It just started and only has one article and some great pics so far.

>

> Birgit

 

This is an EXCELLENT site.  While I was in college I studied with a

professor who looked at some similar casting kilns in

Afganistan and Pakistan.  This guy seems right on, and I

hope to try out some of his experiments (when time permits).

 

Edwin

 

 

Date: Thu, 28 Jan 1999 20:48:51 -0800

From: Edwin Hewitt <brogoose at pe.net>

To: sca-arts at raven.cc.ukans.edu

Subject: Re: Norse kiln/furnace

 

Bronze Casting In Viking Age & Early Middle Ages

http://user.tninet.se/~mfx106d/vikingbronze.htm

 

Edwin

 

 

Date: Thu, 04 Feb 1999 16:21:50 -0500

From: rmhowe <magnusm at ncsu.edu>

To: sca-arts at raven.cc.ukans.edu

Subject: Odd bits of metal / Pilgrims Tokens / Minting Books

 

Whilst groping about the web last nite I came on the following site.

You lot often gab about casting, or minting money, or even the history

of Gallic coinage, British Isles, European, or World.

 

Among other offerings are:

Coin Hoards, Volume I, Royal Numismatic Society, London £10.00

Coin Hoards, Volume 2, Royal Numismatic Society, London £10.00

Coin Hoards, Volume V, Royal Numismatic Society, London, 1979 £10.00

Coin Hoards, Volume VI, Royal Numismatic Society, London, 1981 £10.00

Coin Hoards, Volume VIII, Royal Numismatic Society, London, Greek

Hoards £40.00

 

Cooper, D.R., The Art and Craft of Coinmaking, A History of Minting

Technology, London, 1988, 264 pages, many illustrations, some in

colour £29.50

 

Dekesel, Christian E., A Bibliography of 16th Century Numismatic

Books, London 1997, 1104 pages analysing all known books of the

period, limited to 400 copies, casebound £200.00

 

Metallurgy in Numismatics. Volume 1. Metcalf, D. M. and Oddy, W. A.

(eds.), R.N.S. Special Publication No. 13, London, 1980, 220 pages, 28

plates, cloth reduced to £8.00

 

Metallurgy in Numismatics. Volume 2. Oddy, W. A. (ed.), R.N.S. Special

Publication No. 19, London, 1988, 132 pages, 11 plates, cloth £18.00

 

Metallurgy in Numismatics. Volume 3. Archibald, M. M. and Cowell, M.

R. (eds.), R.N.S. Special Publication No. 24, London, 1993, 296 pages,

38 plates, cloth £40.00

 

Mitchiner, Michael, Medieval Pilgrim and Secular Badges, Sanderstead,

1986, 288 pages, over 1100 badges described and illustrated, covering

Medieval England, 13th century to late 16th century, France, Belgium,

Norway, Germany, Switzerland, Italy, Byzantine and post-Byzantine, and

other artefacts, casebound, 12.5" x 8.5", £30.00

 

(from http://www.netcollect.co.uk/  enquiries at netcollect.co.uk

mail at netcollect.co.uk)

 

                       Collectors Gallery

                 7 Castle Gates, Shrewsbury SY1 2AE

                Tel: 01743 272140 Fax: 01743 366041

                   e.mail m.veissid at btinternet.com

http://www.netcollect.co.uk/MainDealers/C.Gallery%20Main/cg_book_list.htm

.......................................................................

The other principal Pilgrim and Secular Badges books I am aware of

may be had through Oxbow. I've been looking for Mitchener for a bit.

BTW I got the Salisbury Museum Catalog on Medieval Pilgrim and Secular

Badges last week and was very pleased with it. Very clearly illustrated

and a nice selection. There are two. Other books on Medieval Badges

would be Heilig and Profaan, and the Museum of London Medieval Catalog.

 

Oxbow Books, Park End Place, Oxford, OX1 1HN, UK

Tel:(044)-1865-241249 Fax:(044)-1865-794449

E-mail: oxbow at oxbowbooks.com   http://www.oxbowbooks.com/

 

US customers contact: (USA) David Brown Book Co, PO Box 511, Oakville,

CT 06779

Tel: 860 945 9329 Fax: 860 945 9468  Website: http://www.oxbowbooks.com

.........................................................................

Greenlight Publishing has been tracked down if you are interested in

the Detector Finds Series:

Please see www.coins-and-antiquities.co.uk/books.html

Greenlight Publishing

The Publishing House

119 Newland Street

Witham, Essex CM8 1WF

Tel: 01376 521900

Fax: 01376 521901

email magazines at easynet.co.uk

 

I believe the webpage is one short on their historical buckles books

as it lists only six, and the previous page I noted listed 7 books total

published by them. The missing book is:

Guide to Detector Finds : Guide to Dating and Identifying Buckles,

by Bailey, Gordon; Payne, Greg (Ed.)(Retail Price £6.00Each)

 

My impression is that the same books are cheaper, and more fully listed

on the following page:

 

http://www.bookshop.co.uk/ser/serpge.asp?Type=ExactPublisher&;Search

=Greenlight+Publishing

........................................................

Master Magnus Malleus, OL, Atlantia, Great Dark Horde

 

 

Date: Wed, 17 Mar 1999 03:07:51 -0800

From: Twcs <no1home at encompass.net>

To: sca-arts at raven.cc.ukans.edu

Subject: Re: Soapstone? (LONG)

 

I dislike embedding quotes in quotes, but this time it seems the

quickest way to answer the question

 

> > I'd be much more paranoid carving talc and soapstone, which I'm

> > sure people have heard me rant about before  ;-)   > ttfn, Twcs

>

> Definitely interested in the above. Have heard variously conflicting

> information on Soapstone. I.E. asbestos fibers, possible mini-

> explosions to to ferric oxide inclusions. [Magnus]

 

In my stash of jewelry refs, I have at least one citation for casting

into soapstone. (I can't locate it at the moment or I'd cite it here.)

There's hardly any difference, by the way, between massive talc,

talc schist, sericitic schist, steatite, and soapstone. They're all

metamorphic rocks with large amounts of talc and/or sericite in them.

If pale green dominates, it has a lot of talc.  If brown dominates, it

has some ferric oxide in it.  If it's more white than anything else, it

has a lot of sericite ("white mica") in it.  My brown sericitic schist

molds work as well or better than my massive talc ones, by the by.

 

I've never heard about mini-explosions because of ferric oxide

inclusions, but that's not worth much.  Ignorance of something

is not proof of its non-existence.  Anhydrous ferric oxide, Fe2O3,

shrinks a little as you heat it up, but not so much that you could

measure it by eyeball.  Goethite always has a little water in it, so

conceivably, it might give off that water violently if heated up

too quickly.  Steam flashing is much more likely with any stone

mold if 1) you're using it for the first time without having baked it

first, and/or 2) you forgot to heat the mold up before casting

bronze, silver or gold.  Baking any mold is a good idea regardless

of metal or pouring temperature.  Baking it will drive off any water

locked up in the rock, including compositional water in hydrated

minerals like amphiboles, etc.  This is a good thing, since it greatly

reduces the risk of steam flash.

 

It's true: talc and sericite schists might have asbestos fibers as

defined by OSHA.  The danger is inhalation of the fibers, and

little else.  It is clear, however, that asbestosis is an OCCUPATIONAL

disease for asbestos miners and a few others (shipyard workers, e.g.).

Even the gov't will admit to that.  People who work with loose asbestos

fibers at their jobs are at risk; but overall, the general public is not.

 

There's a separate issue here, and that is rock dust in general.  Short

term exposure will give you a hell of a sore throat, and any rock dust

particles in your lungs can act as the nucleation sites for pneumonia.

Long term exposure poses risks to people who work with rocks; namely

as the cause of things like black lung, silicosis and asbestosis, for

example.  What this boils down to is that your soapstones are a concern,

but not a huge hazard because you aren't (I assume) in the rock business;

but it's still a good idea to carve any rock wet to prevent rock dusts.

On the subject of asbestos, try this web site for more info:

http://www.atsdr.cdc.gov/tfacts61.html

 

> Know people who do this[soapstone] instead of slate, which is what

> most of my research shows many casting mold to have been made of

 

Thus far, I have been able to document molds in soapstone, fired clay,

limestone, marble and mudstone.  I think (opinion warning!) that if

they could carve it, they made casting molds from it.

 

> I always defer to someone with better information.

 

*blush*  Actually, I made a commitment to myself years ago never

to post anything without references on hand.  I tend not to post

otherwise, unless I have a question to ask.  I think it's a good policy.

It offers decent protection from foot in mouth disease, and keeps me

from posting frivilously.  The downside is that I occassionally come

across as pedantic.

 

Seriously,  I just have a lot of safety reference material.  To be utterly

honest, I think most safety information is lousy because it's written

in such a way as to be incomprehensible to your average non-nerd.

It's also not something you can zip off to the bookstore and find.

This means that intelligent and concerned people like yourself,

Magnus, have little to no access to decent safety information.  People

aren't inaccurate over material hazards because they're stupid; they're

inaccurate because they limited access to understandable information.

 

I'm not sure why I jump on the safety issues that way I do.  Maybe

it's just a well-developed case of wanting to save the world.  Maybe

I'm trying to prevent someone from doing all the stupid things I

did when I was young.  Go figure.

 

> Are you a chemist or a safety officer?

 

Geochemist and safety coordinator for my lab group.  I also teach

casting at the university craft center when I have the time.

Yipe! This post has gotten much longer than I thought. Time to go.

ttfn, Twcs

 

 

Date: Wed, 17 Mar 1999 13:36:25 -0800

From: Twcs <no1home at encompass.net>

To: sca-arts at raven.cc.ukans.edu

Subject: Re: Soapstone?

 

Magnus replied:

> I'm going to assume we are talking lead / pewter materials here.

> For how slate molds are made and used: <snip snip snip>

 

Time for the old back petaling routine...

Magnus makes an excellent point, which is that mold material

was probably governed by local availability as a first order

effect.  He also makes it clear he's looking primarily at pewter/lead

casting.  That leaves me with a mea culpa on my hands, since I

neglected to mention that most of my casting is with bronze.  So

here goes:

 

oops!  I forgot to mention, folks, that most of my casting is with

bronze.  This means I'm concerned with my molds surviving metal

temperatures between 800C to 1000C.  It also means that I favor

silicates over most other rock types, since they can take the heat.

Since I'll automatically prefer a silicate, using a soapstone is a

natural, since most other silicates are much too hard to carve.

This should explain why I'm paranoid about steam flash

 

> I've more often seen the soapstone ones referred

> to as casting silver.

 

A very interesting observation, Magnus.  I'm now left wondering

if slates, shales, mudstones, etc lack temperature-worthiness for

casting bronze.  Hmmmmm......

ttfn, Twcs

 

 

Date: Thu, 18 Mar 1999 14:28:53 -0500

From: rmhowe <magnusm at ncsu.edu>

To: sca-arts at raven.cc.ukans.edu

Subject: Re: Soapstone

 

Twcs wrote:

> Magnus, a question for you: do any of your refs indicate that sand

> casting might have been period?

> ttfn, Twcs

 

As I have heard generally not in Western Europe before 1600.

I'm a bit dubious on that one. Can't remember seeing it though

so can't prove it. Maybe I missed it somewhere.

 

Certainly in the Far East long, long before that.

They used both clay and sand molds.

At one point the Chinese were producing a billion coins a year in

the 1700's in 36 government mints. Those coins were pretty much

cast the same way for nearly 2000 years. Somewhere, back in several

feet of copies I haven't dug in for many years I have pictures of

the process, but as it was being done in Japanese mints. I spent

about 5 years doing really heavy looking into Japanese monetary

history. I collect oriental currency, including China, Japan, Annam,

Chosen (Korea), etc. It should be noted that the sand in the Yalu

Valley is of a quality similar to the French Sand that jewelers

use from the Paris region. Kind of naturally suitable.

 

Problem is that sand molds don't last in the archaeological record.

Usually the sand gets reused.

Other problem is that only so few people recorded what they did.

Certainly people operating cupolas to refine ore to metal had a clue.

Usually the cupola is drained into sand molds to make pigs.

The pigs are then refined. In the case of wrought iron generally by

having silaceous slag beaten back into them.

 

Then again, in sand molds you can't do complex objects very easily.

So perhaps they stuck with what they had that did work nicely.

My experience with casting intertwined objects is usually that the

sand likes to pull out of corners unless they are on a flat backing

and really well relieved and smooth masters are used.

 

In pre-Viking Scandinavia they were using multiple pieced tempered

clay molds with a removable model. 200 years later it was wax casting.

in generally two piece molds also pressed together over the model.

 

The usual clay molds are damned fragile I'm told.

Anders Soderburg has the Viking Bronze Casting Page:

http://user.tninet.se/~mfx106d/index.htm

A lot of what they do is based on Kristina Lamm's works on Viking

Casting. If you look in the Florilegium under casting you'll see

the citations according to period.

 

Another from Holland:

http://www.angelfire.com/me/ik/index.html

 

The early Britons were using clay molds for their Chariot parts.

Casting rings in rings for bits and such.

Only so many really good foundry sites have been found.

 

Unfortunately, I don't read foreign languages very well, and largely

depend on what I can find in English. A lot of what I have found I

find by ILLing or ordering books from reading Bibliographies.

I also tend to order and take notes from web book search services.

For example I recently recieved two books on Indian Casting with

really low printings trying to record about to be lost crafts.

In one case they used tree resin instead of wax. The mold and

crucible are two parts of the same object often. Casting statues, etc.

I have this idea I want to cast an aquamanile....

 

(Being Dark Horde if the first one succeeds, maybe we'll put the

king backwards on the horse on the next one for the Khan's table.) :)

 

A really good explanation of Statue casting in the Far East was done

in an Arts of Asia magazine about 15 years ago, the process was in

color too. Another in the same series depicted casting Burmese

ceremonial drums. They used easily made lead stamps to decorate

the wax before encasing it in layers of fine clay reinforced with

rice husks before burnout.

 

Magnus

 

 

Date: Fri, 19 Mar 1999 02:34:14 -0500

From: Melanie Wilson <MelanieWilson at compuserve.com>

To: "INTERNET:sca-arts at raven.cc.ukans.edu" <sca-arts at raven.cc.ukans.edu>

Subject: Sand casting

 

>> Magnus, a question for you: do any of your refs indicate that sand

>> casting might have been period?

>> ttfn, Twcs

 

>As I have heard generally not in Western Europe before 1600.

>I'm a bit dubious on that one. Can't remember seeing it though

>so can't prove it. Maybe I missed it somewhere.

 

There is some evidence that brooches of the Pagan Anglo Saxon period in the

Thames region, may have been sand cast, the sand avaliable is very fine &

would be suitable. I believe it was in a Tania Dickerson article, I'll try

& check.

 

>Then again, in sand molds you can't do complex objects very easily.

 

Perhaps not complex but the detail can be quite fine, my AS brooches on my

web page were sand cast.

 

>Yeah, me too.  But what I really want to do is make a bell...

 

Definitely sand cast that! Taylors who are the folk who made Big Ben (Big

Ben for those who don't know is the bell NOT the building it is in) are

about 4 miles from me, they have helped me with my sand casting and are

very bust right now making millenium bells!

 

Mel

 

 

Subject: ANST - Viking Jewellery, Belt Fittings, and Molds from the Frojel Excavation on Gotland

Date: Mon, 03 May 99 08:23:58 MST

From: rmhowe <magnusm at ncsu.edu>

To: sca-arts at raven.cc.ukans.edu

 

http://frojel.hgo.se/News/Volym3/Eng/page1.htm

http://frojel.hgo.se/News/Volym1/index.html

http://frojel.hgo.se/intro.html

Jewellery and molds from Frojel (Dan Carlsson's Project on Gotland).

The New Third Edition of his newletter is the first link.

Dan is also associated with the Viking Heritage Database:

http://viking.hgo.se/

 

If you are interested in Viking Casting please see:

Anders Soderbergs' Bronze Casting in the Viking Age

http://user.tninet.se/~mfx106d/index.htm

 

Magnus

 

 

Subject: Cheap Pewter / Instructional pages / Casting Pages / Examples

Date: Mon, 02 Aug 1999 08:54:47 MST

From: rmhowe <magnusm at ncsu.edu>

To: sca-arts at raven.cc.ukans.edu

 

After Jonathan Blackbow (of Atlantia) suggested getting Pewter from

the Hallmark Metal Co (hallmark.metal at juno.com) 1-888-467-8000

last week I emailed them from their webpage.

http://www.hallmarkmetalscorp.com/

This morning I got an email suggesting I call them.

 

They don't have a catalog, books on casting, or rtv rubbers that I

had asked about. However they do have the lowest prices on Pewter

I've yet run across. (Being a commodity the metal prices are

subject to change however.)

 

I spoke with Stephan M. Kaplan and he told me they have two lead

free pewters particularly suitable for our purposes with the first

designed specifically for children at the request of Crayola.

The initials are named for his child.

 

MPK is a Tin/Copper/Bismuth/Silver alloy melts 5-600 degrees f $4.25 lb.

928 is a Tin/Antimony/Copper alloy / melts 550-650 degrees f $3.75 lb.

 

The bars are available in 7 lbs, and are notched for three pieces

or can be cut at the factory.

 

When I asked about R.T.V. Rubbers he referred me to the

Frank Pertot Co. in NYC. 1-800-627-5369.

 

Check out:

http://www.mindspring.com/~kymber/

There are notes and instructions on casting there as well as other

suppliers, and references.

 

http://home.olemiss.edu/~sputnik/stdunstans/STDhome.html

 

http://www.pbm.com/~lindahl/rialto/idxcrafts.html

 

http://pip1.pipcom.com/wareham_forge/casting.html

 

http://www.loganact.com/mwn/mwj.html

 

http://www.regia.org/bodgbend.htm

 

http://www.regia.org/ has some pages on metalwork as well.

 

http://user.tninet.se/~mfx106d/index.htm

 

http://www.signetring.com/

 

http://renstore.com/articles/Belling_Barony.shtml

 

http://www.angelfire.com/me/ik/Gal.html

 

http://www.mtsu.edu/~kgregg/dmir/new/sandcast.html

 

I hope this is of use to some of you casters or would be casters

out there.

 

Magnus Malleus, OL, Windmasters' Hill, Atlantia, Great Dark Horde.

 

 

Date: Fri, 17 Sep 1999 00:55:32 EDT

From: <DianaFiona at aol.com>

To: sca-arts at raven.cc.ukans.edu

Subject: Re: Aquamanilia - info sought

 

no1home at encompass.net writes:

<<

but this is the other thing that caught my attention! I wish I could

put my fingers on it this very minute, but I have somewhere in this

rabbit warren of an apartment not insignificant documentation on

stone molds for casting viking brooches (one of which is a photocopy

of such a mold from a book on viking/russian archeological finds in

the possession of Lady Katya from the Triasia (sp?) area in Calontir).

Please don't misunderstand me - this isn't to say you're incorrect,

because it's obvious from your posts that you do your homework on your

research. Of course there is more than one way to cast a brooch.  But

in my never-ending quest on good refs for period techniques, could you

please tell me where to find your source on this? I've been stuck

thinking that just stone molds were the way they did viking and other

similar brooches - and now I find I need to stretch my thinking

again...

ttfn, Therasia

  >>

 

    You are indeed correct that soft stone molds were used extensively for

casting in period, but the lost wax technique was even more popular, due to

it's versatility. I love casing in soapstone molds--it's quick and easy, and

you can make as many pieces as you wish that are identical with little

effort. But there are many things that are difficult to carve into a stone

mold--3-D items, for instance, or curved ones, such as the Norse brooches.

For those things, lost wax seemed to be used a lot.

    I'm not close to my info right now, but one book I can remember with lots

of good pictures of broken clay molds, that show the designs that were cast

in them, is a catalog from a museum show called "The Work of Angels," on

Celtic metalwork. Beautiful book! Wish I had a copy, but at least our library

does......... I keep checking it out periodically to drool! ;-)

    BTW, I'd love to see the documentation you mentioned, if you can lay your

hands on it. I'm always looking for more, especially pictures of stone molds!

 

            Ldy Diana

 

 

Date: Fri, 17 Sep 1999 05:09:37 -0400

From: "Peter B. Steiner" <petersdiner at yahoo.com>

To: sca-arts at raven.cc.ukans.edu

Subject: Re: Aquamanilia - info sought

 

Another casting technique which has been used since ancient times is Cuttlebone

casting.  The desired pattern is carved into cuttlebone (the calcium carbonate

endoskeleton of an aquatic creature known as a cuttlefish) - and then metal is

poured directly into the relief carving.  The valuable points of this technique

are that 1) anyone willing to exercise reasonable care (hot metal is always

dangerous unless it is properly handled) can produce good results, and 2)

cuttlebone is available in every pet store on the planet. (Cuttlebones are those

oblong white things people hang in bird cages to allow their birds to keep their

bills naturally abraded.)

This method of casting is easier than lost-wax, though like soapstone casting it

isn't as versatile for the production of 3-dimensional objects.  Cuttlebone has

the virtues of being softer, easier to carve, and more widely available than

soapstone.

I don't want to discourage you from trying soapstone, which is an excellent

choice.....this is simply another Period alternative I thought might interest

you.

 

-Peter-

 

 

Subject: [Metalcasting] Sources for casting supplies.

Date: Fri, 7 Jan 2000 18:14:41 -0500

From: "Jim Revells" <sudnserv5 at netway.com>

To: <Metalcasting at onelist.com>

 

Here are some sources for casting supplies:

 

DRS, (800) 223-8960  NY, NY:  silver & gold Casting Grain, pg3, Cuttle Bone

pg 297, Crucible/Melting Dish pg 296, Heat protective gloves pg 294,

Carving Wax pg 278.

 

Cas-KerCo, (800) 487-0408 Cincinnati, OH  on the web at casker at casker.com:

non-precious Casting Metals pg 146,  Carving Wax pg 162, Small Sand Casting

Set.

 

Other companies that I don't have the current catalogs for but sell Casting

supplies (they all have 800 #'s):

Swest, Atlanta, GA

FireMountian Gems, somewhere in WA

Rio Grand, El Passo,TX

Stuller, somewhere in LA

 

Suggested Reading:

 

Practical Casting, Tim McCreight

The Complete Metalsmith, Tim McCreight  Also a Vidio is available.

Soapstone Carving for Children, Bonnie Gosse

 

Suggested Site to visit:

http://user.tninet.se/~mfx106d/vikingbronze.htm

 

Lrd Olaf of Trollhiemsfjord

 

 

Subject: Plans for Kiln

Date: Mon, 14 Feb 2000 13:06:13 -0800

From: John Grant <grantjoh at pacbell.net>

To:  Metalcasting at onelist.com

 

Todd wrote:

> What I really want is something affordable, small, portable, and able to

> melt a few pounds of brass/bronze, propane fueled would be a plus.

>

> Does anyone have plans for building something like this?

 

What you want is called a “crucible furnace”.  They are easy and

inexpensive to build.

 

Start with a 5 gallon can with an open top.  Cut a 1-1/2 inch diameter

hole in the side of the can about 4-1/2 inches from the bottom.

 

Get a bag of “ramming mix” from a foundry supply house.  Ramming mix is

a type of heat resisting cement used for repairing large furnaces.

 

Using very little water, mix enough ramming mix to fill the bottom of

the can about 4 inches deep.  Pack it hard.

 

Next you need a piece of tube, close to 5 inch od.  about 10 inches

long.   Any stiff material will do, like plastic or cardboard concrete

form tube (Sonotube).   Cut a 1-1/2 inch diameter hole in the side of

the tube to line up with the hole in the can.

 

Place the tube, centered in the can and insert a 3/4 inch pipe through

the holes in the can and the tube, so that the pipe is tangent to the

inside of the tube.  This may require a little filing of the can and

the tube holes.

 

Next mix some more ramming mix and start packing it between the tube and

the can, being very careful that it works around the pipe completely.

Fill the space between the can and the tube to the top of the can,

packing tightly.

 

While this is drying, make a steel ring the diameter of the can about

3 inches high.  Weld a pair of handles to the ring and a bunch of 1/8

inch rods about 3 inches long to the inside of the ring.

 

Put the ring on a solid flat surface, place something about 3 inches in

diameter with a taper to it in the center of the ring and pack the ring

full of ramming mix.

 

Let things dry for a day or two and you are ready to start the final

drying.  Build a wood or charcoal fire in the furnace, pop the plug out

of the cover and place it on the furnace.  You will want to heat the

furnace slowly, over several hours.

 

Do not try to get the tube out of the furnace, just let it burn away.

 

After several hours of heating you are ready to get serious.  Connect a

hair dryer or small vacuum cleaner blower to the pipe and bring your

metal tube from the propane tank to the intake of the blower.

 

To me. a crucible furnace just “sounds right”  when you have the correct

air and gas mixture.  I do not know any other way to describe it. There

will be a fairly loud roar when things are adjusted right.

 

Choose a crucible about 1-1/2 to 2 inches smaller in diameter that the

inside diameter of your furnace.  I cannot find my list of crucible

sizes, but I think a #2 or #3 will be what you want.  The number refers

to the pounds of aluminum the crucible will hold.  Bronze weighs three

times as much as aluminum.

 

Cut a piece of fire brick about the diameter of the crucible.  Place

this in the furnace and place a sheet of cardboard between the firebrick

and the crucible, load the crucible with metal, start the fire and away

you go.  In about one hour you should have your first few pounds of

metal melted.  The cardboard is to keep the crucible from sticking to

the firebrick.

 

Of course, you will need a pair of tongs to lift the crucible out of the

furnace and another set of tongs to hold the crucible for pouring.  A

face shield is useful too.

 

John Grant

 

 

Date: Tue, 14 Mar 2000 18:58:46 -0500

From: rmhowe <magnusm at ncsu.edu>

Organization: Windmaster's Hill, Atlantia, and the GDH

To: Metalcasting at onelist.com

Subject: Re: [Metalcasting] Re: Patterns for Clay Casting

 

I do a lot of my patterns in ABS or styrene plastic.

It gives very fine detail. I buy it at places like Commercial Plastics

or the local hobby shop.

 

I find that xeroxing an illustration works well to get an item to size.

I always make more than one so I'll have something to work to.

The one for the pattern gets coated with rubber cement and I glue

it to the plastic. Then I cut through the paper with an X-acto blade.

I peel off the paper and either quickly put on a bit of marker

and rub it off leaving some in the lines or if the plastic is white

just the dirt on your grubby paws will leave lines to work to.

 

Cut your pattern out with a jeweler's saw or scroll saw once you drill

The holes in the waste areas.

 

I generally use engraving burins to work with and refine the work

with scrapers made of dental tools. I do a little bit of filing.

 

I do a lot of fine sanding and I've found one of the most useful tools

is a Flexifile (TM) with small sanding strips strung across it.

You can cut the strips thinner for small details or split them for inside

curves. You should be able to buy burins at Brownells.com/ and most

of the rest of the stuff at Micromark.com/

Look under chisels at Brownells.

 

What kind of graver?

Well, I usually use a square ended one to set in with next to my lines

and do outside curves. These come in various widths. For inside depressions

I generally use a round one. You really don't need a big assortment for

this like you would for jewelry work. Most of your refinement would

be by scraping and sanding.

 

I also use sanding sticks, the kinds with little belts on them.

You can also find these at Micromark.

 

It's important to realize that for sand casting you can't leave any

undercuts to pull out your sand on removal.

 

Either that or get used to carving out excess sand with a bit of a

coke can bent into a scoop. I know another laurel who's become a

master at this. He can do spurs in sand molds, very detailed ones.

He uses Petrobond sand by the way. Rougher castings, but then he is

an armorer by trade professionally and has the polishing equipment

to clean stuff up in an instant.

 

Of course he also uses Sculpey and similar oven hardenable clays

to make some of his patterns, casting of many kinds is well practiced

in Atlantia. I simply prefer plastic patterns because of the finish

I can get on the item and I know I'm not going to break it ramming

in sand.

 

I generally rap the pattern with a dental tool I use to cut the gates

in and mine falls right out when I turn the mold over. No prying it

out if you've done the right relief work.

 

(Incidentally, I was at different times a furniture foreman, cabinetmaker,

modelmaker, and plastics fabricator who made molds for a living.)

......

If you must use wood I recommend either Poplar or basswood (lime is the

European equivalent). Basswood carves easily but it is quite soft,

but not so bad as many pines.

 

The problem with pine (and most conifers) is the alternating

seasonal grain. Sugar pine is likely the best if you must use it.

Walnut cuts very well if your tools are very sharp but it's

quite hard and a bear to sand. It does get grainy in places.

 

Oak is rough and it splits something terrible and is very

grainy for small work. It does sand easily though, since it's so dry.

 

Poplar will take the best overall finish - the grain is extremely

tight.

Cherry is what's generally used by patternmakers.

 

Magnus Malleus, OL

Atlantia, GDH

 

> From: "Jim Revells" <sudnserv5 at netway.com>

> I plan on using pewter for my first atempts, then after I get the items

> finalized, use silver.  I'm sure the silver will burn the clay worse.

>

>  I've been working on wood forms to make the impresions of a Thor's Hammer

> & plan to start some belt plates as soon as I can get the walnut I've been

> promised.  I have found that Pine is not good for fine detail (too easy to

> split off while carving.

> Hej!

> Olaf

> ----------

> > From: "Heather Watkins" <qamara at yahoo.com>

> > I have used this system for brass casting.  I found that it worked

> > great.  Good detail and very easy to use.  I was unable to reuse a

> > lot of the clay because the brass "burned" the clay.  The pewter

> > didn't heat it up near as much.  Great to one time projects. Just

> > remember to really pack the clay.  The more compressed the clay is

> > the better the detail.  Of course, YMMV.

> >

> > Qamara

 

 

Date: Sat, 20 May 2000 09:04:20 MST

From: gunnora at realtime.net

Subject: ANST - Re: Pewter/tin

To: ansteorra at ansteorra.org (ansteorra)

 

Polydore asked:

>Can anybody suggest a source to ingots of pewter or tin?

>(Lead-free) to cast with? So far, the cheepest I have been able

>to find is for about $9.65 US/ pound, which seems a bit high

>and is from a retail store.

 

There were two very knowledgable Laurels at the last Pennsic I attended who

were doing period pewter casting, esp. buttons, pilgrim's medals, and the like.

At least one of the ladies (the one I'd spoken with) had done considerable

experimentation with alloys, amounts of tin, trace metals added, etc.

 

Since they both were merchanting there as well, I'd guess that they've both

had to face the same problem of obtaining raw materials, and may well have other

useful thoughts on this topic.  

 

One place to check would of course be the last three years' Pennsic booklets

in the lists of merchants.  I will also ask on the SCA-Wide Laurels' List and

see if I can get more information for you.  I'll post back here ina day or

two when I get some info back.  SInce I've moved recently, I have no idea where

my Pennsic booklet may be, but maybe some of you Pennsicgoers could look and

post the names and contact info for the pweter artsists?

 

Stafan li Rous also suggested:

>If you are using soapstone to carve the molds for your casting...

 

There are a variety of period mold materials as well.  I think Stefan had tried

some casting into hardwood (yes?  how well did this work?) and I know for a

fact that the Vikings cast into antler.

 

I've done a little silver casting into antler molds.  You want the hard, solid

part of the antler, not the spongy inner sections, of course.  The antler should

be fairly fresh, i.e., not dried up, cracked and powdery due to long exposure

to the elements.  

 

I soak antler for this for about two weeks in cold water, then boil about 2-3

hours before carving my mold. Before casting, you want the insides of the antler

"moist", but not wet -- as the hot metal goes in you don't want steam produced

that will make tiny bubbles in the casting.  I've found that if I cast within

a couple of days of carving the mold without further soaking or wetting, then

that's about right.

 

Of course, you get a "burning hair" smell from the antler when you pour the

hot metal.  But I've found that the mold survives quite well and can be reused

several times.

 

If you decide to go with antler for molds, unless you're doing something pretty

tiny the whitetail antlers we have around here aren't big enough.  The best

commercial source for antler, and one that's surprisingly affordable, is Moscow

Dead Animal Bits (Moscow Hide and Fur, http://www.hideandfur.com). Moscow has

the big advantage of allowing you to buy only tines, or only beams, or only

palms (i.e., from moose antler) rather than making you spend a fortune to buy

a whole huge rack.  This is very useful for craftsmen.  

 

::GUNNORA::

 

 

Subject: RE: ANST - Re: Pewter/tin

Date: Sat, 20 May 2000 11:17:07 MST

From: "j'lynn yeates" <jyeates at realtime.net>

To: <ansteorra at ansteorra.org>

 

[mailto:owner-ansteorra at ansteorra.org]On Behalf Of gunnora at realtime.net

> and I know for a fact that the Vikings cast into antler.

 

in just about every bronze and early-mid iron age celtic site where

metal casting was done, you will find numerous bone molds, especially

for the finer, jewelry grade work (and stone for the courser,

industrial "production" level work)

 

> I've done a little silver casting into antler molds.  You want the

> hard, solid  part of the antler, not the spongy inner sections, of

> course. The antler should  be fairly fresh, i.e., not dried up,

> cracked and powdery due to long exposure to  the elements.

 

in the past, i've used dense bone for molds for silver & bronze with

good result for small pieces ... for the bone molds, i snag the large

cow femur's sold as soup bones at my grocery, & toss them to the

hounds as "treats".  after they and the ants have cleaned them, i

pick them up and toss them in the bone-box prior to mowing.  when

mold material (or doing a bone piece) there's a ready supply of

thick, dense bone ready to be worked for whatever is required (makes

nice hair and clothing ornaments ... and blackens nicely)

 

'wolf

 

 

Subject: [Metalcasting] Vikingbronze - new URL

Date: Fri,  9 Jun 2000 09:55:09 +0200 (MET DST)

From: anders.sberg at spray.se

To: Metalcasting at egroups.com

 

New URL to Vikingbronze:

http://hem.spray.se/anders.sberg/index.htm

 

Please help me tell those who might be interested! It will be hard for

me reaching everyone who might have bookmarks to my page, not to

mention the sites that may have links to it!

 

Anders Soderberg

 

 

Subject: [Metalcasting] RTV Suppliers and Personal Observations

Date: Fri, 28 Jul 2000 17:52:56 -0000

From: "Guillaume de St. Michel " <theatrix at att.net>

To: Metalcasting at egroups.com

 

My wife and I have been using a 2 part Silicone RTV to cast pewter

medallions for several different projects over the past two years.  

So far we have been using the following supplier (they supply people

who like to cast their own miniatures).

 

CASTINGS, A DIV. OF REB TOYS, INC.

P.O. BOX 298

Eastsound WA 98245-0298

(360)376-3266 (8:30am-5:00pm pacific coast time.)

 

For orders call:

1-800-346-0567

Fax: (360) 376-3280

 

http://www.miniaturemolds.com/mainframe.htm

 

The price varies according to quantity bought.  I normally buy it in

1-gallon (11 lbs) amounts.  The cost of 1 gallon ranges from a high

of $170 to a low of $136.  The $136 is special price if you order

through the website, click on the "Monthly Internet Specials" link.  

They also offer mini "starter" kits, which include all of the basics

(melting post, mold material, clamps, ladle, etc.  (And no, I am not

affiliated in any way with the company; they have just been very

helpful and responsive to us).  The also have some pages which have

simple casting tips.

 

The 2-part RTV will take around 600 degrees without breaking down,

which has worked fairly well for my purposes.  I use a

standard "reloading" thermometer to check the temperature of the

material (I basically just leave it in the pot).  I had one mold that

I accidentally cast at over 600 degrees for about 13 castings.  The

mold went from a firm, semi-rigid, consistency, to jello like

consistency in the middle of the mold.  I believe that the excesses

heat "killed it".  Since that time I have been very vigilant

about

watching the molten metal temperature.  

 

Our castings have ranged from medallions about 1 1/4 inches in

diameter and about 3/32" thick to some monster medallions that were 2

inches in diameter and 1/4 inch thick.  Casting large items in the 2-

part RTV seems to put a lot of stress on the mold (causing them to

degrade more quickly).  I think this is because the larger castings

transfer a lot more heat into the RTV mold than the smaller

castings.  However, my wife and I did cast over 300 of the "big"

medallions using 2 molds with 3 "positions" each.  We would cast each

mold 5 times (giving 30 medallions per session) and then let the

molds cool off for about 30 minutes to an hour.  During this cool

down time we would trim/clean up the 30 medallions and buff them.  

After the molds were cool, we would re-blacken the molds again with

graphite and beginning the process again.  

 

SIDE NOTE: By the way I have been referring to the cycle of steps

used to cast items, i.e. that of clamping the molds, pouring the

metal and then pulling the castings out as "1 pull".  For example in

the process described above, we would do 5 "pulls" and then let the

molds rest for 30 minutes to one hour.  If there is a different, more

correct, term to describe this please let me know.

 

I keep a log book of all of our casting work, time required to make

the models, the materials used to make the model, Mold material used,

mold status/damage, Pewter alloy used, metal temperature, number of

good castings, number of bad castings per batch, etc. for reference

later on.  If anyone is interested, I can check the numbers we have

on how many "pulls" we got from some of the different projects.  We

cast over 800 of the smaller 1 1/4 by 3/32 medallions using 2, 3-

position molds and over 300 of the large medallions.  We still have

the molds for these two projects and while they are beginning to show

wear; we still can get good castings out of either of the two mold

sets.  Please note that each set of molds does have one or two bad

casting positions, so now we only get 4 to 5 medallions per cycle.

 

One other nice thing about the 2-part RTV is that you can repair

molds during production.  One mold I used for the small medallions

split/tore lengthwise through all three positions after about 30

cycles/pulls.  I thought the mold was finished and I made a new mold

to replace it.  While I was making the new mold, I had a bit of

catalyzed RTV let over and I thought "what the heck, I will try to

glue the mold back together".  So I painted the catalyzed RTV into

the tear, carefully aligned the torn edges and clamped the mold

tightly and wiped off any excess RTV that "oozed" out of the seam.  

 

To my surprise, the repair mold worked like a champ.  2 of the repair

positions in the mold came out perfect.  In the middle position, the

torn edges did not line up correctly and a very visible seam line was

apparent in castings poured in that position.  However, two out of

three wasn't bad for a mold that I was ready to "write off" the night

before.  I then used the repaired mold along with the new one to

finish the 800 castings.

 

I have been very impressed also with the fidelity and the flexibility

of the RTV material when casting.  It can reproduce incredibly fine

details (i.e. fingerprints in the clay around the model) and also can

survive having undercuts in the mold for multiple castings.  The

vertical edge of the large 2 x 1/4 medallion mentioned above was

inscribed in Latin about 1/16 deep.  Even with this undercut all the

way around the edge, the RTV would release just fine and bounce back

to be cast again.

 

The company also carries other "low temperature" casting materials

such as "QUICK-SIL®" which can take around 900 degrees (according to

the accompanying literature).  I have used the Quick-Sil and it was

not as "user friendly" as the Silicone RTV.  Quick-Sil is very thick

and putty like and take a lot of pressure to conform to your

model/master.  I have had problems with voids in the mold.  Its

strengths are that it will take a higher temperature than the two-

part RTV and it cures in less than 1 hour (vs. 8 hours to overnight

for the 2 part RTV).

 

Last but not least they company carries " VULC-A-MOLD" which is a

rubber like, sheet material, that you clamp in frame around your

master and cure in the oven.  I have not used it, so I don't have

any  comments on it.

 

I have heard about using the automotive style, high temperature,

silicone compounds, but I have not experimented with them yet.  I

would be interested in hearing how well they work (fidelity,

durability, cost).

 

Lord Guillaume de St. Michel, OHA

Lady Christiana de Mandeville, OHA

 

 

Subject: Re: [Metalcasting] Plaster of Paris molds

Date: Tue, 29 Aug 2000 11:24:44 -0600

From: "Smoke" <Smoke at 5stargr.com>

To: <Metalcasting at egroups.com>

 

>I am casting pewter.

>What is the process of making reusable molds using plaster of paris.

>Give books or step by step for the complete/ new idiot.

>Jasper

 

Making plaster molds for pewter is very simple:

 

Since you want reusable molds, you have only two choices...open face

molds or closed split molds.

 

First prepare the part by waxing or spraying with silicone or other

mold release agent.  Open faced molds can simply be laid on top of old news

paper or aluminum foil.  I usually use old aluminum sheets I get from the

local print shop.

 

Split molds do not REQUIRE the use of a mold box, but you will have to

build up around the part to the parting line with clay or some other

material. When doing this, be sure to put in at least two locating projections

in your material if necessary.  These will serve to properly locate the mold

halves for later reassembly.

 

The most important part for a quality plaster mold is proper mixing of

plaster.  The best way I've found or heard of to do this is to start

with cold or luke warm water (don't use hot water) and add plaster to the

water as follows:  gently sprinkle the plaster over the surface of the water

by hand until the top surface of the water has a coating of plaster

remaining on top.  Let the plaster soak a minute or two and then gently feel the mixtures for any lumps and sqeeze to remove the lumps.  This method

provides both a consistent ratio between the plaster and the water and helps

prevent addition of air bubbles caused by stirring.

 

After about five minutes you can start applying the plaster.  It will still be somewhat runny at this point so you will gently cover the part with a very thin layer of plaster, making sure there aren't any air bubbles contacting the part.  The rest of the plaster is added a bit at a time.  It will be obvious when you try putting too much on at one time as it will run off the part.  The part that runs off can always be scooped up and put back on top later.  Cover the part to a depth of at least 1/2 ".

 

The next most important part would be curing the mold.  Let it dry naturally

for a dayor two.  A week is even better....which we have to do for slip cast

ceramic molds.

 

Before your ready to pour you need to slowly raise the temperature of the

mold to just below pouring temperature by heating it in an oven.  This is

done in stages.  First bake it for an hour at about 200 degrees to drive out

any remaining water.  Turn up the temp to 400-450 degrees and let in bake

for another hour.

 

At this point the mold can be taken out and the metal poured.  The easy way

to support the mold for pouring at this time is in a bed or dry sand. For a

split mold, heap the sand around the sides of the mold to hold the mold

halves together.

 

You can get a book called "Ornamental metal Casting" from Lindsay

publications if you want more info.

 

Smoke

 

 

Subject: Re: [Metalcasting] My 1st pound of coins.

Date: Thu, 07 Sep 2000 18:29:06 -0800

From: John Grant <grantjoh at pacbell.net>

To: Metalcasting at egroups.com

 

LLandstrom wrote:

> You can bring the design to any rubber stamp place and

> they can acid etch a magnesium die for you. I pay

> about 3-4 dollars per square inch and usually there's

> a minimun fee of around $20.00.

 

Or you can send your design to:

Owosso Graphic Arts

151 N. Delaney Rd.

Owosso, MI 48867

800-444-5552

 

They charge about $1 per sq.in. for magnesium and a little more for

copper.

 

These photoengravings are two dimensional.  There is the raised

surface and the etched surface  about .035 inch below.

 

I use these as patterns for spin casting in rubber molds.

 

John Grant

 

 

Date: Wed, 27 Sep 2000 19:35:56 -0400

From: rmhowe <MMagnusM at bellsouth.net>

To: - Norsefolk <Norsefolk at eGroups.com>

Subject: Vikingetidens Metalbearbejdning - Viking Period Metal Working Up

 

Some of you may be on the MetalCasting at egroups.com list on

which a number of the posts have been on Viking period

metalcasting in sand/clay molds by Anders Soderburg of Sweden,

an experimental archaeologist and Sandy Sempel of the Australian

New Varangian Guard. If you'd like to see these go to www.egroups.com

and search MetalCasting, there is a searchable backlog of postings.

 

Recently Anders recommended a book when I asked him when he was going

to write one. His articles are on the web. Viking Metal Casting Page.

http://hem.spray.se/anders.sberg/index.htm

 

Anyway he recommended:

 

Vikingetidens Metalbearbejdning

(Viking Period Metal Working Up)

by Bjarne Lo/nborg.

Odense Bys Museer

i kommission hos Odense Universitetsforlag.

(Odense University Printing)

Odense University Studies in History and Social Sciences Vol. 203.

Fynske Studier 17, 1998

ISBN 87-7838-259-9 or ISSN 0078-3307.

Odense bys Museer

Publksum & Kommunikation

Postboks 1255

5100 Odense C

Tlf. 66 14 88 14 - 4601

Fax 65 90 86 00

email museum at post.odkomm.dk

 

I got the book about a month ago. It's a rather small paperback,

and maybe because I ordered it through Oxbow and they don't usually

carry it it ran me about $57 U.S. I think, maybe a little less.

 

It runs about 140 pages, very well illustrated. In Danish with

English translations (very complete) below each illustration and

a 31 page English summary with notes to illustrations in the back.

There are 85 illustrations with subsequent maps, appendices, and

a multi-language bibliography which is quite large.

 

The raw materials, tools, furnace, numerous molds, techniques,

and artifacts are pretty well illustrated, including a period

drawplate.

 

I've got about 450 books on metalwork and jewelry and I was rather

pleased with it, even at the higher than I would have expected price.

It's a whole lot easier to obtain than say a 1943 set of Oldeburg's

Metalteknik, and it's got a good section in English, and is pretty

understandable. Some of the techniques I hadn't read of before

elsewhere.

 

Magnus Malleus, OL, Atlantia, Great Dark Horde

 

Permission to repost to closed email lists within the reenactor

community granted, but NOT to newsgroups,

especially the Rialto - rec.org.sca.

 

 

From: gunnora at my-deja.com

Newsgroups: rec.org.sca

Subject: Re: Soapstone Molds

Date: Fri, 15 Dec 2000 16:08:02 GMT

 

Duncan von Halstern asked:

> I was thinking of doing some casting but I can't find any info on how

> to use soapstone for making the molds. Does anyone know of any good

> web sites?

 

Try http://www.egroups.com/group/Metalcasting

 

How exactly you make a soapstone mold depends on what you're doing.

 

You can carve your mold for an item with a flat back right into the

soapstone, heat the mold in your oven for best results then pour right

into the impression.

 

Alternately, if you are making something that has detail on both sides

or is more 3-D, then you need to have a soapstone block thick enough to

contain your hypothetical item, then saw the slab in half.  Then you

carve your mold in two halves.  It's a very good idea to consider

registration pins to make sure your mold lines up right, and allow for

a pour channel and sprue channels.  Once you're done, clamp the mold

halves together, heat the mold, then pour.

 

I often will use a sand casting for 3-D items thoughm because it's

easier to set up.  You build two trays for the sand with registration

pins at the edges, then fill with sugar sand (very fine masons sand

mixed with molasses).  If you have a positive of the item you're

wanting to cast you can often just press it into the mold, or close the

mold halves on it in order to get your mold ready, add sprues and a

pour channel.  Then you clamp the mold halves and pour.

 

The Metalcasting list on eGroups will allow you to talk to people who

are actively using these techniques, tho, so you'll get the best help

possible.

 

::GUNNORA::

 

 

From: gunnora at my-deja.com

Newsgroups: rec.org.sca

Subject: Re: Soapstone Molds

Date: Fri, 15 Dec 2000 20:56:20 GMT

 

Thomas <wtp at nds10758.cb.lucent.com> asked:

> Gracious ::GUNNORA:: what metals do you pour in "sugar sand" molds?

> Do they hold up to fine silver?

 

"Sugar Sand" is the name I learned when I took the sandcasting class.

I've cast silver and bronze in 'em.  The quality of the finished

casting will be directly proportional to the fineness of your sand

grains, and you want the texture of the molassas-sand mixture to be

such that it holds a good clear impression without crumbling, running,

cracking, etc.

 

You can actually buy casting sand premixed - check the Rio Grande

catalog or your local jeweler's supply.  But it's cheaper to buy the

finest mason's sand you can get and some blackstrap molassas and mix it

yourself.

 

::GUNNORA::

 

Gunnora Hallakarva, OL

Ansteorra

 

 

From: rlobinske at aol.com (Richard Lobinske)

Newsgroups: rec.org.sca

Date: 16 Dec 2000 13:12:43 GMT

Subject: Re: Soapstone Molds

 

>"Sugar Sand" is the name I learned when I took the sandcasting class.

 

Have to grin a bit.  Down in Trimaris, sugar sand is the fine white sand found

in the sandhill and scrub areas of the kingdom, exposed areas look very much

like large spills of granular sugar.  

Come to think of it, properly seived, I think it would make good casting sand.

 

Victor Hildebrand vonn Koln

mka Richard Lobinske

Trimaris

 

 

From: jhrisoulas at aol.com (Dr JP Hrisoulas)

Newsgroups: rec.org.sca

Date: 16 Dec 2000 16:15:26 GMT

Subject: Re: Soapstone Molds

 

Sand casting?? Hell's bells..I use sand castings for everything from bronze to

gold to steel...if you have the experience and the know how it's a very good

way to do it..Not that I know all that much about metalworking....

 

Atar

Dr JP Hrisoulas

Metallographer, Lecturer

Author:  The Complete Bladesmith

The Master Bladesmith

The Pattern Welded Blade

http://www.Atar.com

 

 

Subject: RE: [Metalcasting] Plaster or Paris Molds

Date: Mon, 23 Oct 2000 18:20:59 -0400

From: "Westfall, Rob" <Rob.Westfall at usa.xerox.com>

To: "'Metalcasting at egroups.com'" <Metalcasting at egroups.com>

 

I have made molds from Plaster of Paris.  We had a project to cast 1500 pewter coins for a upcoming SCA event.  We knew that a single place mold was not going to be  practical for this project, so we looked at methods to create a multiple piece mold for and plaster of paris was one of the techniques that we played with.

 

I worked on this project with Jan Tucker (Lavena). She made some inquiries in  September on the topic of "My 1st pound of coins"

 

To start, we created a single place mold, from slate, to cast a set of pewter  "master" coins.  These were intended to be used to create a secondary mold capable of casting many coins in a single pour.  This single place mold was used to cast about two hundred coins before it broke into pieces.

 

We also attempted to create a multiple piece mold out of slate, but had a lot of  problems with the slate chipping on the coin edges and we eventually abandoned  the large slate mold.

 

To create the plaster molds, we placed the master coins in clay, surrounded it with a wooden frame (Legos work good too), and poured plaster over the top, and let it set. We then removed the plaster from the frame, cut some alignment marks, coated everything with release (sprayed on vegetable oil), and poured plaster over that.  When it was hard, we separated the two sides, cut spurs, vents and gates and started to use it.

 

The first mold worked pretty good. I made the mold, and then it sat at my house  for about a week, and then we baked it at 200 for about an hour and poured pewter.  One side of the mold broke in half after 4 or 5 pours, but we kept poring in the  unbroken sections.  It lasted for 11 pours, and we got about 100 coins from the pour. The mold consisted of 6 rows of 4 coins, for a maximum of 24 coins per pour. Each row was individually gated, so that a break in the mold would not destroy the entire mold.

 

Based on this success, I made two more molds.  These we started to use almost immediately, after baking them for 1 hour at 200 degrees.  This was not long enough.  We ended up baking them for a total of about 4 hours before we got enough water out of the mold that they were not steaming when we poured. This was working pretty good, except that the coins coming out with alot of flash around the edges.  

 

We also noticed that they we heavier than the originals poured from the slate mold - 70 coins per pound instead of the 120 per pound that we got out of the slate mold. We ended up with being able to do about 10 pours in the plaster mold before they died.  Successive pours had a loss of detail and a increase in flash on the edges.  The molds also cracked and broke into two or more pieces after 5 or 6 pours.

 

We eventually abandoned the plaster mold, got some different slate and created a smaller multiple coin slate mold.  This was used to create the rest of the coins.

 

I do not recommend plaster of paris molds for ANY kind of quantity work. A couple of good pours is all you are going to get from them.  They are create to make, easy to modify, but they do not last very long.

 

Rob Westfall

Steffan Wolfgang von Ravensburg,  Barony of Thescorre, Kingdom of

AEthelmearc

Rochester, NY

 

 

Date: Sat, 12 May 2001 10:53:01 -0600

From: "Ellen SMITH" <Ellen.Smith at oag.state.tx.us>

To: <stefan at texas.net>

Subject: metal casting

 

http://nhsouth.com/crafts/workbench/

 

 

Date: Fri, 03 Aug 2001 14:50:26 -0400

From: James Koch <alchem at en.com>

Newsgroups: rec.org.sca

Subject: Re: Lost Wax / Plaster casting query

Organization: EriNet Online Communications - Dayton, OH

 

Jonathan Blackbow wrote:

> Just to show you a good example of functional fixedness, I assumed that if

> you were doing anything with plaster, you were carving the design out of it.

>

> 1.  If I have a medallion model and want to make a plaster cast of it to

> cast pewter into,

>     a.  How do I make a back, i.e., two part mold?  what do I use after I

> cast the front half to keep the plaster back half from sticking to the

> plaster front half?    Will Silicone release work?

>     b.  if my original is made out of super sculpey, how do I get it out of

> the plaster mold?  Will silicone release work on that too?

>     c.  How good is the detail on plaster casts?

>     d.  How many pewter critters will I get out of one plaster mold before

> the plaster loses all its detail and I have to make another one?

>

> Any answers or info will be appreciated - I'm trying to find a cheaper /

> quicker alternative to Ditto 2.

>

> Jonathan Blackbow

 

Jonathan,

Quite a bit depends on the original you are attempting to copy.  You may

have to experiment and determine what works best for you.

 

a)  Simply press the original into the wet plaster in such a way as to

eliminate bubbles.  You may have to daub the piece with wet plaster to

fill depressions.  Make sure the mold surface is as smooth and level as

possible.  Once the front half is made, cover it with cellophane or a

heavy coating of some other parting compound such as wax, Thompson's

Water Seal & etc...  I am not familiar with silicone release, but if

plaster will not stick to it, then it ought to work.  Then pour on the

backing plaster.  The original must have no undercuts.  Otherwise it

will break the mold when you try to remove it. If the original does have

undercuts you will do well to use a vinyl molding compound obtainable

from craft supply companies.  This is a powder which when mixed in water

forms a rubber like mold.  You can then pour casting wax into the rubber

mold and make multiple copies.  The rubber mold can be stored for a few

weeks but will eventually oxidize and crack. The wax copies can have

sprues and vents attached and can then be immersed in plaster.  No

parting of the mold is necessary since the wax will be fired out in a

kiln.  Plaster molds have to be fired whether wax is used or not to

totally eliminate water.  This must be done slowly and for several

hours.  Otherwise the mold will explode from steam pressure when the

metal is poured.  A lost wax mold will produce only one item.  You might

get several from a two part mold depending on the complexity of the

design.  However, plaster molds are not rugged.

 

b)  You ought to be able to pry the original out of the wax without any

release, but using silicone can't hurt.

 

c)  Plaster casts give incredibly good detail.  Better than the unaided

eye can see.  I once lost wax cast a gold ring.  The wax original had

fingerprints on it's sides since I expected to have to sand and buff the

surface anyway.  Once cast, to my surprise, the fingerprints were

perfectly visible in the gold!

 

d)  As stated above, you might only get one two or three casts out of a

plaster mold before it flakes to the point that detail is lost.  For

more rugged molds I recommend cuttlefish bone, soap stone, wood or

metal.  I once cast about 30 pewter Celtic crosses in a basswood mold.

I have gotten inlimited casts out of a copper mold.  With copper though

making the original is time consuming and you get bad casts until the

mold gets hot enough.  The mold will have to be fitted with handles like

a bullet mold, or you will have to wear gloves to manipulate it.

 

Jim Koch (Gladius The Alchemist)

 

 

From: Hjordis Olvirsdottir <julesong at eons.com>

Newsgroups: rec.org.sca

Subject: Re: Lost Wax / Plaster casting query

Date: Fri, 03 Aug 2001 13:10:27 -0700

Organization: Eskimo North www.eskimo.com (800) 246-6874

 

This won't answer your question, exactly, but...

 

There's a really good bronze casting set of webpages at

http://hem.spray.se/anders.sberg/index.htm

 

--Hjordis

 

 

From: jhrisoulas at aol.com (Dr JP Hrisoulas)

Newsgroups: rec.org.sca

Date: 11 Sep 2001 14:07:56 GMT

Subject: Re: silver for casting

 

Seanan:

 

The answer all comes down to how much do you need and where you are located.

 

Sterling silver (.925% pure) costs more the pure silver bullion.  I do alot of

silver castings for sword fittings and SLTT so I have found it beneficial to

alloy my own Sterling using bullion and pure Cu wire by weight.

 

Most jewelry supply places sell Sterling casting grain and you can usually find

silver bullion at the larger coin shops or at bullion dealers. Personally, the

way I look at it, it's much more cost effective to go with the bullion and wire

than the grain, but I am set up for pours up to 50 lbs... Your situation is

probably not the same as mine... so...

 

Get ahold of a tellow pages and look under either gold/silver, precious metals

or coins...

 

Hope this helps..

atar

Dr JP Hrisoulas

Metallographer, Lecturer

Author:  The Complete Bladesmith

The Master Bladesmith

The Pattern Welded Blade

 

 

From: wtp at nds10758.cb.lucent.com (Powers)

Newsgroups: rec.org.sca

Subject: Re: silver for casting

Date: 11 Sep 2001 16:13:27 GMT

Organization: Lucent Technologies, Columbus, Ohio

 

>Can anyone point me to a source for silver suitable for casting?

>-Seanan

 

1: get a copy of the paper and look in the business section for commodity

prices, (ours has a section labeled "Metals") and look for the "spot" price.

 

(US$4.180 troy oz IIRC) this is what it sells for in massive ammounts on

the market.

 

2: call pawnshops, coin dealers, gold and silver dealers and ask what they

are selling for.  Often given as "spot + $x.yy buy from the cheapest source.

 

I go to a local coin shop that sometimes has 1 oz sterling rounds as well

as fine silver ones.  Sometimes you can get a better deal on 10 oz bars.

If you are buying 100 oz ingots it's time to deal with a major player in

the market...

 

W.Thomas Powers

 

 

From: David Razler <davidrazler at home.com>

Newsgroups: rec.org.sca

Subject: Re: silver for casting

Date: Tue, 11 Sep 2001 20:16:51 GMT

 

Yard sales can also be sources of underpriced Sterling (check purity

marks, weight and remember most knives are hollow shells with

stainless blades).

 

I forget how pure US coin silver *was* but scrap coins (worn silver

disks) are frequently available - sometimes at an obscene markup by

folks selling them as 'investments'

 

In Philly, I know if I go to Jeweler's Row, I can get all the silver

.999, Sterling, coin, in any form for a fairly fixed price above spot

at several supply ships. I use Hagstotz because the outfit has been

good to supplying various SCAdians with small orders. I could get the

same deal at 4 other spots...

 

                                -d/A

 

 

[submitted by Phlip <phlip at 99main.com>

From: "Roy Wilson" <rwilson9 at twcny.rr.com>

To: "theforge at mailman.qth.net" <theforge at mailman.qth.net>

Date: Tue, 12 Feb 2002 20:33:21 -0500

Subject: Re: [TheForge] Foundry letter sets

 

On Wed, 13 Feb 2002 10:59:52 +1030, Shannell wrote:

>While on the sand casting topic (barely :)) saw a good tip the other day,

>use fine grade cement mix and 10w motor oil as your casting mould material,

>very fine detail and easily available.

 

      Don't use "cement", what you want is "finishing mortar".

It's all fines, no grit or lumps.

 

Roy Wilson

General Operations Director

Zanzibar Internet Land Line Administrator

 

 

Date: Tue, 19 Mar 2002 19:42:10 -0500

From: rmhowe <MMagnusM at bellsouth.net>

To: Jane and Kenneth / JSEStudio <JSEStudio at AOL.com>,

   - Atlantia <atlantia at atlantia.sca.org>,

   - Regia Anglorum - North America <list-regia-us at netword.com>

Subject: Casting sites

 

http://www.bronzeagefoundry.com/

 

http://www.frojel.com/ has pages full of artifacts

and a complete casting section from building a Viking Age

furnace, making the crucibles and molds from clay and

up to 80% sand, pouring and breaking the molds.

 

http://home.attbi.com/~klessig4/Page.htm

Pages of various kinds of European and Asian (coins) molds.

 

Magnus

 

Do NOT pass this on to the Rialto or any other newsgroup.

SCA or reenactor elists or individuals are fine.

Reason - argumentative types and spam robots.

 

 

Date: Tue, 19 Oct 2004 09:41:53 -0400

From: "Jeff Gedney" <gedney1 at iconn.net>

Subject: Re: [Sca-cooks] Charcoal forge suggestion ;-)

To: Cooks within the SCA <sca-cooks at ansteorra.org>

 

Never pour really hot metals into a cold mold...

 

When possible, especially when doing finicky work like investment

casting, preheat the mold.

 

Here's a investment casting trick I learned a long time ago...

using fine liquid clay, about the consistency of pankcake batter, dip

the wax form several times allowing it to only partially dry between

dippings until the coating is an even 1/8 inch thick, then air dry it

as normal...

Then place the mold on paper towels on a ceramic plate, sprues down,

and put it in the microwave on low for 10 mins, remove the towels,

microwave on low for an hour, then on high for 15 mins.

(dont do this if you are using metal at all in the form or mold, this

is for purely Wax forms)

 

Then place the mold on the fire and let it slowly come to temp BEFORE

you add blast air. Then and only then put in the crucible, in the same

fire, and add blast air to melt, then pour, then cool slowly.

If you make every effort to drive off moisture before pouring you will

get far fewer spectacular accidents.

When pouring very hot metals (600 degrees F and above) go SLOW and take

each step carefully.

 

Capt Elias

 

 

Date: Wed, 20 Oct 2004 10:55:13 -0400

From: "Jeff Gedney" <gedney1 at iconn.net>

Subject: Re: [Sca-cooks] casting

To: Cooks within the SCA <sca-cooks at ansteorra.org>

 

> However, rather than explicitly heating the mold in the oven or

> whatever, I recommend simply pouring in the pewter a few times. This

> will heat the mold sufficiently so that soon you should get clean

> castings. The first ones, done into the cool then warmer mold, I

> simply recycle by tossing them back into the melting pot.

 

That's ok is you are using soapstone which is anhydrous, but not so

good if you are using clay or plaster molds, which absorb water from

the air, and especially not possible if you are doing "investment"

casting, were the mold can't be reused (Investment casting is done

often in Jewelry making).

 

Capt Elias

 

 

<forwarded by Phlip <phlip at 99main.com>

From: "Bill Schongar" <bschonga at cisco.com

To: <EKMetalsmiths at yahoogroups.com

Sent: Thursday, January 06, 2005 9:54 AM

Subject: RE: [EKMetalsmiths] Re: Metal Casters Out There

 

> Ok, quick question...

> Liam, are you casting the 500 and 1800 in soapstone?

 

Yup. Though the token I'm doing 1800 of will (this year) be in a soapstone mold that casts 4 at a time, so it'll only be 500+ pours. I've been told that soapstone will not cast in large quantities as it gets hot and breaks. They're partially right - it gets hot. : )

 

The most castings I've ever done in one mold was for last year's Birka, where I did 1700 Thor's hammers (a variation on the Romersdal find (http://www.odin.org/th650.htm)) one at a time in the same mold.

 

Counting discarded castings, that mold was cast in over 2000 times last year. And it's still fine. Is there a trick to getting the stone casting longer?

 

Hmmm.. I can think of three things that might fall into that category... - Quality of the soapstone - Temperature of the pour - Casting method - Design of the mold Soapstone quality - It's possible that some people have used soapstone which fissures or fractures more easily at high temperatures, as I know there are different types... but that's as far as my geology knowledge extends.

 

I get my soapstone from Lee Valley Tools (www.leevalley.com), in the small block size at around $13 per block. That gives me anywhere between 5 and 10 molds, depending on whether they're double-sided or not.

 

Temp - If pewter is above its optimum casting temperature that could affect the longevity by subjecting the stone to more thermal stress/shock than needed. I use a casting thermometer anytime I'm doing lots of castings, to be sure I'm in the correct pouring range for the alloy I'm using.

 

Methodology - If you take a cold mold and shove overheated pewter into it, your mold won't appreciate it. While sometimes I'll do this anyway, most times I'll heat up the mold slightly by pouring pewter onto the design face, let that sit there for a sec, then start the normal pouring. I'll typically also do only 40-50 sequential pours into a mold before letting it cool a little (this is mostly due to my oven mitts/welding gloves getting too hot to be comfortable, since I hold the mold during the entire casting process)

 

Design - Not aesthetics, but the mechanical/structural design of the mold. All my molds tend to be made from 1/2" (or thicker) slices from the block of soapstone. Thin soapstone is brittle. Make sure to eliminate all undercuts so designs fall easily out of the mold - any extra stress of prying/levering designs out causes mold damage (been there, screwed that up).

 

-Liam

 

 

<forwarded by Phlip <phlip at 99main.com>

From: "Avery Austringer" <avery1415 at sbcglobal.net

To: <EKMetalsmiths at yahoogroups.com

Sent: Thursday, January 06, 2005 1:54 PM

Subject: [EKMetalsmiths] Soapstone Durability fo Pewter Casting

 

I've been told that soapstone will not cast in large quantities as it gets hot and breaks. Part of the problem is that "soapstone" is used to describe at least four different geological entities, some of which are more suitable for casting than others.

 

I've got at least one mold (the Pennsic 30 annular broach teacher's token) that handled 600 pours with no sign of deterioration. I've had very good luck with material from Lee Valley (www.leevalley.com). It handles the heat well, has reasonable hardness and durability, very few fissures, minimal mica, only a few granules of pyrite. (Remember that we're dealing with a natural product so there is going to be some piece to piece variation.)

 

I've worked with other material that was much softer and easier to carve and had virtually no impurities, but lots of fissures and low durability, and some that a guy at Pennsic sells that is as durable as granite, but about as difficult to carve (a Dremel tool and diamond burs do a good job). I've also seen stone that pretty much turned into talcum powder if you left it in black car on a sunny day. Paper mache would be a better mold material than that. (Don't laugh, I've made pewter bar with some rolled up notebook paper and cast a greatsword pommel in a mold made out of poster board and strapping tape.)

 

As for heat, a couple thoughts: For most things the mold has to be warm to the touch to cast properly. Some things will cast in a cold mold (some things like it) and some need a too hot to touch with your bare hand mold. A lot of people overheat their metal. If your are getting purple oxides on your metal within a minute or two of cleaning off the slag, you are probably doing this. When I cast, I wear a pair of medium weight work gloves. When I can't hold onto the mold any more wit those it's time to go make some coffee or something.

 

The bigger you make your gate, the more metal will end up cooling there and the more heat that will be going into your mold. There are some advantages to having a large gate - hydraulic (or maybe I should say stannic?) pressure - but at some point you're just making your mold hot and burning more fuel to remelt your metal.

 

You can manage heat, somewhat, via the thickness of the stone you are using. At the simplest level a mold with thin walls will warm up faster, handle fewer pourings before it is too hot to work with, and cool faster than a mold with thick walls. There are tricks you can play with that last phenomenon. I had a button mold that, after it warmed up, invariably developed voids in it's face when the metal cooled. By cutting the front thinner and setting it on a piece of 1/4" steel plate during casting (to draw the heat away) I was able to get the face to harden first and pull metal down from the gate.

 

Avery

 

 

From: Stefan li Rous <StefanliRous at austin.rr.com>

Date: February 24, 2007 12:08:31 AM CST

To: Coblaith Mhuimhneach <Coblaith at sbcglobal.net>

Cc: Barony of Bryn Gwlad <bryn-gwlad at lists.ansteorra.org>

Subject: Re: [Bryn-gwlad] books on period pewter

 

On Feb 22, 2007, at 1:09 AM, Coblaith Mhuimhneach wrote:

>> There are multiple books that are filled with pictures of medieval

>> pewter work and several, two that are quite thick, which are

>> filled with mostly photos of pewter pilgrim badges.

>

> Could you recommend some good titles, particularly on early-period

> stuff and badges (secular as well as religious)?

>

> Coblaith Mhuimhneach

 

Greetings Coblaith,

 

Since others might be interested in this, I'm going to copy the list

on this as well.

 

Here are some books mentioned in my class handout:

_The Complete Metalsmith_ (ISBN 0-87192-240-1) by Tim McCreight.

_Practical Casting_ (ISBN 0-9615984-5-X) by Tim McCreight.

Soapstone Carving for Children, Bonnie Gosse

 

On period pieces:

_Pilgrim Souvenirs and Secular Badges_ By Brian Spencer ISBN 0 947535

128

 

_Medieval Pilgrim and Secular Badges_ by Michael Mitchiner, Sanderstead,

1986, 288 pages, over 1100 badges described and illustrated, covering

Medieval England, 13th century to late 16th century, France, Belgium,

Norway, Germany, Switzerland, Italy, Byzantine and post-Byzantine, and

other artefacts, casebound, 12.5" x 8.5", ú30.00

 

Period works:

_De Re Metallica_ by Georgius Agricola (ISBN 0-486-60006-8)

_The Pirotechnia_ by Vannoccio Biringuccio (ISBN 0-486-26134-4)

_On Divers Arts_ by Theophilus (ISBN 0-486-23784-2).

 

Here are some additional books which I have:

_Pewter: A Celebration of the Craft 1200-1700_ by Hornsby, Peter R.G.

(ISBN 0-904818-36-5)

Museum of London, London, 1989

_Detector Finds_ by Bailey, Gordon (ISBN 1-897738-02-1) Greenlight Publishing

_Detector Finds 2_ by Bailey, Gordon (ISBN 1-897738-01-3) Greenlight Publishing

_Detector Finds 3_ by Bailey, Gordon (ISBN 1-897738-22-6) Greenlight Publishing

 

The above four are all 8 1/2 by 11 inch, about 100 page paperbacks,

and were around ú12.00 each.

 

_Salisbury and South Wiltshire Museum Mediaeval Catalogue: Pilgrim

Souvenirs and Secular Badges_ by Spencer, Brian (ISBN 0-09-475351-2)

Salisbury & S.Wiltshire Museum. 1990. 144 pages. ú12.95

 

*If* you can find this one, I highly recommend it. However, I know I

got the last one at Pennsic when I bought it and it was a remainder

then. It is one of the most expensive books I've ever bought (~$90)

but it is a large book, 10 x 14in.?, 288 pages full of pilgrim badges

and the holy water vials. You might be able to find it cheaper though

from some used book venders.

_Medieval Pilgrim and Secular Badges_ by Mitchiner, Michael. (ISBN

0-904173-19-4) Hawkins Publications. 1986

 

The Museum of London also publishes a thick (1 inch thick?) book

similar to the one above but like most HMSO books it is high priced,

especially for a paperback. I don't have it, so I don't have the

title and ISBN readily available.

 

No badges but lots of buckles:

_Buckles 1250-1800_ by Whitehead, Ross (ISBN 1-897738-17-X)

Greenlight Publishing. 1996

This next one has a few badges, but mostly other artifacts.

_Medieval Artefacts_ by Mills, Nigel (ISBN 1-897738-27-7) Greenlight

Publishing. 1999

 

Stefan

--------

THLord Stefan li Rous    Barony of Bryn Gwlad    Kingdom of Ansteorra

     Mark S. Harris           Austin, Texas

 

 

From: mmagnusol <mmagnusol at nc.rr.com>

Date: March 28, 2007 2:53:54 PM CDT

To: - AncientArtifacts <Ancientartifacts at yahoogroups.com>

Subject: Viking Bronze Casting Page has changed.

 

Many of you are aware of Anders' work as an experimental

archaeologist.  If you know someone with an Arts & Sciences

links webpage likely they will want to change it.

 

Magnus, OL

_______________________________________________________________________

 

1. New Viking Bronze URL!

   Posted by: "anders.sberg at spray.se" anders.sberg at spray.se vikingbronze

   Date: Tue Mar 27, 2007 8:19 am ((PDT))

 

Metalcasters!

 

My Viking Bronze web site has a new address:

http://web.comhem.se/vikingbronze/

 

And tell your friends! :)

 

Best Regards,

 

Anders S

 

 

From: Brian Ferguson <bjf10 at the-immortals.com>

Date: June 24, 2007 11:54:58 AM CDT

To: pewterersguild at yahoogroups.com

Subject: [pewterersguild] Mold mentioned at lionhearts...

 

Hi all, 

I saw this mold in the archeology museum in Istanbul and thought of you 
all. It's a stone mold from the 7th or 8th century BC, that was used 
for casting bronze fibulae and pins. It looks like it has holes for 
register pins, but they only had one half of the mold on display (I'm 
not sure if they even have the other half.)

 



http://www.flickr.com/photos/derianlebreton/593703810/&#8232;
-Derian.

 

 

 

From: Chris Fuhr <instructorhasgonedigital at yahoo.com>

Date: June 24, 2007 12:34:58 PM CDT

To: pewterersguild at yahoogroups.com

Subject: Re: [pewterersguild] Mold mentioned at lionhearts...

 

Two of the smaller objects are for pewter beads the sides show where they put the insert so they didn't have to drill it. That's a four part mold not including any two part funnels to guide the metal into the mold. They used two parts for the fibulas and the pins and would place a third and up to a fourth for the beads.

 

The beaded half circle matched a separate mold (same pins) and the back plate had a full donut shape. End results would have been a full Fibula that you would have soldered something to 1/2 the front. This would have allowed for the Jeweler to change the designs on one half the fibula. It's easy to make the bead pattern continue for a bead or two and then carve something in the middle. You could even make one the was just a shield (just and example) and hand the casting off to the guy who would carve(metal removal) the coat of arms in the shield (again just an example so no one needs to go wrong time or wrong culture)

 

----- Original Message ----

From: Brian Ferguson <bjf10 at the-immortals.com>

 

I saw this mold in the archeology museum in Istanbul and thought of you

all. It's a stone mold from the 7th or 8th century BC, that was used

for casting bronze fibulae and pins. It looks like it has holes for

register pins, but they only had one half of the mold on display (I'm

not sure if they even have the other half.)

 

http://www.flickr. com/photos/ derianlebreton/ 593703810/

 

-Derian.

 

 

From: Katira <naquiba_katira at yahoo.com>

Date: July 24, 2007 4:29:45 PM CDT

To: pewterersguild at yahoogroups.com

Subject: Re: [pewterersguild] New to pewter casting and this group

 

> I've been doing pewter casting for years and have never used sodium

> silicate powder. How are you intending to use it?

>

> Stefan

 

The powder is mixed with the soapstone dust and water

to create a paste that can be used to fill in carving

errors and to build a tinker's dam around the sprue if

needed. I know it isn't necessary, but a handy thing

to have around.

 

If you are interested, I will post my uses of it.

Thanks for the links.

 

Katira

 

 

From: Katira <naquiba_katira at yahoo.com>

Date: July 24, 2007 5:20:51 PM CDT

To: pewterersguild at yahoogroups.com

Subject: [pewterersguild] use of sodium silicate

 

--- Anne-Marie Rousseau <dailleurs at liripipe.com> wrote:

> I'd be interested as well...do we have any

> indication on the periodness of this technique? I know

> we sometimes will use epoxy to repair "OMG I JUST

> DROPPED MY MOLD" and other disasters ;), but

> using something more period approrpirate would of

> course have a great appeal for me :)

>

> --AM

 

Cannot say to the periodness. It was what was taught

to the class by 2 Laurels. I don't expect it is.

Using it for a little dam around the sprue opening

lets you use an oddly shaped end piece for the button

shank mold you set on top of the button head form and

lets you get more for your buck out of your hunk of

soapstone. The concept of frugality is certainly

period if not the method ;-)

 

If anyone knows what they used in period to fix

mistakes and help channel the pewter, we'd all like to

know.

 

Katira

 

 

From: Jim Fry <farmersgf at yahoo.com>

Date: July 26, 2007 10:44:08 PM CDT

To: pewterersguild at yahoogroups.com

Subject: Re: [pewterersguild] use of sodium silicate

 

For sodium silicate try... eBay.com, ..ScienceLab.com, ..cqconcepts.com, ..shop.com, or ..CataloogLink.com

 

Jim -in Ohio

 

Katira <naquiba_katira at yahoo.com> wrote:

The teachers said it would be hard to find. Nothing

local I could find. Finding powder in a small

quantity is hard. If it was available, it was in way

too large quantities for what I need. I found a site

with free samples but they wouldn't ship to California

so I asked a friend in Nevada to request a sample for

me. I don't want to give out the name of the site and

have it unindated with requests for free samples.

 

If/when I get my supply I will post my experiences

with it. My soapstone chunk has an end piece I can

see using it to make a little dam around the sprue for

easier pouring. I have my first carving that I want

to use it to fill in some.

 

If anyone finds a source for small quantities of

powder form, please post it!

 

Another use for it is to preserve eggs!

http://www.chemistrystore.com/sodium_silicate_uses.htm

 

fyi, the site only sells it in solution.

 

Katira

 

 

From: Gustav Minnesinger <synrik at earthlink.net>

Date: October 6, 2007 8:16:58 PM CDT

To: "Kingdom of Ansteorra - SCA,Inc." <ansteorra at lists.ansteorra.org>

Subject: Re: [Ansteorra] ISO Pewter casting Information

 

-----Original Message-----

> From: Elizabeth Blackthorne <damsle_n_distress2003 at yahoo.com>

>  I have a member in my shire looking into learning how to cast  

> pewter site tokens, and where to get the supplies online.  He has  

> ordered already a kit from ebay and is now trying to find a  

> soapstone dealer.  Any help would be appreciated.

>

>  Elizabeth Blackthorne

>  Seneschal of Crossrode Keep

 

The main questions would really be: Do they want to make them in a  

period manner?  How many will they be making?  How much post-casting  

work do they want to do?

 

The period methods for multi-part molds would be making a negative  

from soft-stone (soap-stone, soft marble, etc.) or making a positive  

from clay (terracotta, grey clay, etc.)  Through bone, cuttle-fish  

bone, and wood seem to be a logical choice as well, I have yet to see  

proof that it was used in period (due to the molds decaying).  All  

the other methods date back to the dawn of metalworking (3500BCE).

 

The good points is that they are Period; and due to the  

?quenching? properties of the stone/clay, it comes out of the mold  

looking rather polished and still retains a little of it?s

flexibility.

 

The down side is that carving a negative requires a bit of practice,  

there can be no under-cuts at all, and the number of uses before it  

looses resolution or is destroyed is rather low (10-30). Stephen has  

said that he has gotten over a hundred tokens out of a single mold,  

but he is a master in Period soap-stone molds  . . . . an I am almost  

certain there was Voodoo involved.  Then again, it may also have  

something to do with my complete lack of skill in carving.

 

So if you are going to use period methods, be prepared to make 12-15  

molds . . . and hope that none of them fracture or will not release  

the token.  If you have the time, enough helpers and a small event  

planned, going period is pretty cool for the site tokens. But it is  

not for beginners or for large events . . . . or if is all being done  

by one person.

 

As for the period-like molds (modern materials, period methods).

 

Carved negative molds: carved wood, carved linoleum, carved plaster  

of Paris (when you cannot get soap-stone), etc.; these have similar  

draw-backs as the period methods, but are easier to get a hold of.  

You just have to be sure that it will not go up in flames at 450*F.

 

Molds from a positive: RTV (Wal-mart), clear silicon caulking,  

professional mold rubber.  These are some of the things I like when  

doing site-tokens.  It allows for undercuts because it is flexible.  

And because it is flexible, you don't go through as many molds due  

to facture or loss of resolution.  You can also make them a bit more  

detailed as well.  In period, a medallion would be poured into a  

stone mold, then it would go to a carver who would carefully carve in  

all the details that was missed in the mold, then to a polisher, then  

to a painter, etc.  Using flexible mold rubber, you can punch out  

about 600 site tokens a day per person with a good Dremel tool on  

hand.  They can be double sided, funky shapes and detailed enough to  

have inscribe writing on the inside of the ring.  Even prongs for  

stone setting.  And rings, well that is something that cannot be done  

(and have it look good) using period methods without a cadre of  

apprentices on hand.

 

This is from experience.  5,700 site tokens flung far and wide,  

hundreds of buttons and more burns than I would really like . . . . .  

Because it is all a one man operation.

 

Gustav Minnesinger

Jeweler and Singer of Night Songs

 

 

From: Brandon McDermott <brandonsmcd at yahoo.com>

Date: October 6, 2007 9:47:41 PM CDT

To: "Kingdom of Ansteorra - SCA, Inc." <ansteorra at lists.ansteorra.org>

Subject: Re: [Ansteorra] ISO Pewter casting Information

 

I worked for reaper minis making molds and slight amounts of sculpting, and we used "green stuff" .... Look it up on ebay or at reapermini.com. It is a two part epoxy putty. I also comes in brown ( good for flat or super smooth finishes ) and white ( too brittle ).

  Lochlan

 

brendan_mcewan at dhope.net wrote:

  use bondo as your mold medium. They can either carve a positive and pour the bondo around for a mold, or the more difficult way, pour the bondo and carve a negative. Much cheaper and easier to acquire than soap stone. Also, most carvers don't have experience carving a negative.

 

Brendan

 

----- Original Message ----

From: Elizabeth Blackthorne

To: Kingdom of Ansteorra - SCA Inc.

Sent: Saturday, October 6, 2007 4:51:06 PM

Subject: [Ansteorra] ISO Pewter casting Information

 

I have a member in my shire looking into learning how to cast pewter site tokens, and where to get the supplies online. He has ordered already a kit from ebay and is now trying to find a soapstone dealer. Any help would be appreciated.

 

Elizabeth Blackthorne

Seneschal of Crossrode Keep

 

 

From: Guillaume de Garrigues <guillaume at garrigues.net>

Date: February 29, 2008 7:21:04 PM CST

To: pewterersguild at yahoogroups.com

Subject: Re: [pewterersguild] Small intro and soem questions...

 

Raven Mayne spake thusly:

<<< How dangerous/lethal is the dust from soap stone?

Suggestions/hints on how to stay safe?

 

Second question needs a small explanation.

 

I was talking to some one who has been doing some amazing soapstone

carving for pewter casting and I asked what he does about keeping all

the dust down from carving. He said he does all his carving in the

garage not only because of the dust but the pewter fumes.

 

I have been working with pewter for some years now and no one ever

mentioned "pewter fumes". Any thoughts?

 

-Raven MAyne >>>

 

There are two things to consider with soapstone itself:

      •     Make sure you have a reliable asbestos-free source.  This isn't a major issue with reputable suppliers, but if in doubt, ask.

      •     Avoid making the dust airborne while you are carving.  In general, this is just good debris management practices (don't blow the dust off your mould, keep a small refuse container handy, use a placemat to catch dust, etc.) 

As Alysaundre mentioned, the dust itself isn't toxic, it's just a bad idea to breathe any fine particulate.

 

As for the idea of "pewter fumes" I've never noticed molten pewter having a distinct smell or giving off fumes of any kind when used in combination with an electric heating element (sometimes a new electric pot will smoke when first heated, because of the protectant oil applied by the manufacturer, but this never lasts more than a few minutes, and has nothing to do with the pewter).

 

It's never a bad idea to do pewter work in the garage though -- spills happen, both with dust and molten metal, and molten metal in particular is hard on things like carpet. 

 

A well ventilated work area is always a good thing, of course, wherever that might be.  But with good dust management practices, you can carve safely nearly anywhere.

 

Guillaume

 

 

From: Chris Fuhr <instructorhasgonedigital at yahoo.com>

Date: March 2, 2008 4:07:38 PM CST

To: pewterersguild at yahoogroups.com

Subject: Re: [pewterersguild] Re: Small intro and soem questions...

 

When you say clay please be specific. A fired clay is different than a non-hardening clay.

 

Non-hardening clay with sulfur in it makes it that RTV options are not possible. (I'm not suggesting that anyone should do anything differently just this is where some-people go off track) If you are at the choosing stage and are looking at non-hardening clay, choose one without sulfur. It only takes a moment, costs about a buck more and is less hassle and leaves the option of making a back up mold.

 

Hardening clay will need a release direction nonhardening clay can be ripped apart in the separating of the plaster mold from the master model. (Warning you only get one shot at it this way)

 

 

From: Judy Picard <judypicard at yahoo.com>

<<< I have been working with clay and making molds from potter's plaster and had a class in making pewter medallions. I'm thinking/planning to make coat of arms medallions by this method:

 

      1.    making some medallions in clay then

      2.    making a plaster mold from the clay

      3.    cut a pour hole [sprue?] in the plaster then

      4.    pour in the pewter

      5.    paint portions of the front of the metal with the acrylic paint we use on bisque [somewhat porous semi-finished ceramics]

      6.    spray the front with clear polymer [seals bisque and makes it more washable]

Would acrylic paint applied to medallions peel or wear off during normal SCA use?

Because of pewter's low melting point and health concerns, I've ruled out baking dry enamel on the medallions.

If not acrylic what about Tester's model car paint? Acrylic paint for glass?

 

Emerald of Wexford

aka Judy Picard

Celtic Corner >>>

 

 

From: "Nigel Haslock" <FiachaMacN at hotmail.com>

Date: March 3, 2008 2:29:47 PM CST

To: pewterersguild at yahoogroups.com

Subject: [pewterersguild] Re: Small intro and soem questions...

 

In general, plaster is too friable. That means that you might get a good 
casting from a plaster mold but you probably won't get two. What happens is 
that tiny bits that provide the detail stick to the casting when you try to 
take it out of the mold.

 

A reusable mold needs to be made of a more durable 
material, which is why we generally use soapstone. Carving a negative sounds 
more difficult than it turns out to be. Keep a lump of Sculpy handy to check 
you carving every few minutes and you should do fine.



 

However, if you really want to make the positive and take a mold from it, 
try this.

 



Make the master from Fimo or Sculpy, and cook it when you are happy with it.



Make the mold from either RTV rubber, or from a clay that you can bisque 
fire.



Your approach to coloring the result should work but the question about wear 
is going to depend on what you do with the finished piece. Pendants that are 
worn with lots of other pendants get a lot of bashing, belt fittings may or 
may not while hat pins rarely get knocked about.

 



My feeling is that period pewter decorations were not painted and so our 
reproductions should not be. Jewellery was decorated with gems and enamels 
and so was extremely valuable and generally handled accordingly (would you 
wear a $5000 item where it might get bashed about?). If you go to the 
trouble of decorating your piece to emulate an enameled piece of jewellery, 
you should wear it as though it was worth $5000 or more. You should also 
think about the question of would your persona have owned such a valuable 
item.



 

Regards



   Fiacha


 

 

From: "Anne-Marie Rousseau" <dailleurs at liripipe.com>

Date: March 4, 2008 9:24:19 AM CST

To: <pewterersguild at yahoogroups.com>

Subject: [pewterersguild] on painting pewter pieces

 

Hi all from Anne-Marie

On painting pewter pieces….

I know that Master Mark has several extant pieces of pewter that show traces of polychrome (ie paint) on them. There are also examples in the many catalogs of extant pieces. Paint would be an easy cheap way to mimic the more expensive enameled bits in period

That said, they didn’t use low fire enamels (ie the modern paints that you can fire to hardness in your regular oven) of course J. But if you’re going for an effect, the low fire enamels on pewter seems like as good an approximation as any. (personally I’d love to play with various period paints and see how it works on pewter. I bet it does, with the right base coat and top coat...gesso and period varnish, maybe? Goodness knows that combination works great on wood bits that get banged around a lot. And if it wears off, you just reapply it. No biggie.)

For me, what makes something acceptably period looking is if it captures the medieval aesthetic. Ie does it look like one of the jillions of extant pieces? Or does it look like a modern, or 18-19th century piece? Is it thick? Or is it thin, like a real one? (I’m sure there were thick pieces in period too, but medieval me wouldn’t have bought one, as they would be more expensive and not of as high of workmanship)

And of course, YMMV. I am fully aware that not everyone is into doing things authentically, nor are they required to. But I’ve found over my years of doing this that using medieval materials and methods is often the easiest way to get closest to a medieval looking object.

-AM

 

 

From: Brian Ferguson <bjf10 at the-immortals.com>

Date: May 12, 2008 10:44:32 AM CDT

To: pewterersguild at yahoogroups.com

Subject: Re: [pewterersguild] Looking for books to document sand casting.

 

> Could anyone recommend good books to help me document sand casting???


> -Raven


 

The earlist description of the process I've seen is in Biringuccio's _De 
La Pirotechnica_, from 1540.



 

-Derian.



 

 

From: Stefan li Rous <stefanlirous at austin.rr.com>

Date: July 24, 2008 2:49:28 AM CDT

To: pewterersguild at yahoogroups.com

Subject: Re: [pewterersguild] Introduction!

 

On Jul 24, 2008, at 12:48 AM, Veronica wrote:


> I'm picking soapstone up tomorrow to work on my first piece which


> is...Site Token for Dragon's Mist Defender Tourney. I was asked and


> have been looking and researching and finally came to the all mighty


> Yahoo groups to find a place to go to for ideas. Low and behold this


> group has surfaced! Tomorrow I shall me going to pick up my slab of


> soapstone. The smallest chunks they have are 5lbs and I believe it is


> Brazillian green.

 

> We don't have a bandsaw, so if someone could recommend a good saw to


> use in it's place for cutting that would be lovely. We do have a midar


> saw, but I'm unsure if that would work?


 

Provided you are using a softer soapstone and not one that has been 
hardened for use in cabinet tops and such, you can cut it with almost 
any saw. Don't do what I did the first time and pay the stone shop $5/ 
cut to cut it on their diamond saw.



 

I started out using a simple carpenters saw. I then moved to a miter 
box with a built-in saw. Unfortunately, this one did not have a 
replaceable blade and after several years of cutting soapstone with 
it, I had dulled the blade too much to be of use. Since I couldn't 
find a replacement saw in the same size, I ended up eventually buying 
a nicer miter box which used a saw with replaceable blades.



 

However since most of the soapstone I cut is to get 20 to 30 pieces 
at one time for my pewter casting classes, hand sawing all this got 
to be a pain and when I inherited my father's electric cut-off/miter 
saw I replaced the metal circular saw blade with a ceramic disc. This 
worked fine until I burned out the bearings in the motor.

 

My current 
saw is also an electric cut-off/miter saw but it will let me move the 
head back and forth as well as up and down, which allows me to cut a 
piece of stone with an 8 in. by 4 in cross-section rather than just 4 
in. by 4 in.

 



A bandsaw might be even better since you might be able to eliminate 
the vertical 4 inch restriction, but it will also be more dangerous 
with more unshielded blade, I believe. Unfortunately I don't have the 
space in my shop for one of the larger floor mounted bandsaws, which 
I'm thinking of.



 

But if you are only cutting a few blocks from time to time, a good 
carpenters saw should work just fine.



 

Stefan


--------


THLord Stefan li Rous Barony of Bryn Gwlad Kingdom of Ansteorra


Mark S. Harris Austin, Texas 
StefanliRous at austin.rr.com

 

 

From: Arqai Ne'urin <arqai_n at yahoo.com>

Date: July 24, 2008 1:19:22 PM CDT

To: pewterersguild at yahoogroups.com

Subject: Re: [pewterersguild] Introduction!

 

A mitre saw will probably work okay for small cuts. If you have a 51 pound slab, you'll probably want a powered saw. Whatever saw you use, make it dedicated to the purpose of cutting soapstone. Once you use it to cut stone, you'll probably not be able to use it for anything else. I've been using a 10 inch cutting wheel on my table saw for cutting stone and it is working very well. I don't have to sand or re-saw to get the surface smooth enough for carving.

 



A.





 

From: Sean Wales <sean.wales at comcast.net>

Date: July 26, 2008 2:21:05 AM CDT

To: pewterersguild at yahoogroups.com

Subject: Re: [pewterersguild] How many casts?

 

On Jul 26, 2008, at 12:08 AM, Brian Ferguson wrote:

A mold made of good stone without any undercuts should be able to handle 
thousands of casts.

 



-Derian.



 

> How many casts can you get out of a soapstone mold? I'm curious


> because I'm doing the mold for site tokens and need to know if I need


> to make multiple molds or if one will hold up. They're doing less than


> 300 site tokens.


> 


> Veronica


----------------

 

Yeah, so far, the most I've gotten out of a mold is 800 tokens.  I even drop and broke it in a couple places and patched it up and it kept casting.  300 shouldn't be a problem.

 

-sean

 

 

From: Chris Fuhr <instructorhasgonedigital at yahoo.com>

Date: July 26, 2008 1:26:30 PM CDT

To: pewterersguild at yahoogroups.com

Subject: Re: [pewterersguild] Re: How many casts?

 

This is the area that Soap Stone out shines RTV.  RTV has the advantage of forgiving undercuts but your lucky to get a hundred casts.

RTV is not to be confused with fully Vulcanized Rubber Molds.

 

 

From: "Anne-Marie Rousseau" <dailleurs at liripipe.com>

Date: July 27, 2008 2:14:28 AM CDT

To: <pewterersguild at yahoogroups.com>

Subject: RE: Re: [pewterersguild] Re: How many casts?

 

<<< Has anyone tried creating a ceramic mold and casting pewter in that? If one succeeded in keeping the ceramic from cracking, would the differing expansion properties of the ceramic and the pewter make it impossible to use as a mold?

Red Bow >>>

 

We have extant examples of molds in clay. Multiples were production cast using this method, its very cool J. I don’t know if we can tell from the molds if the object cast were pewter or not, but it seems the thermal properties of brass vs pewter would both work just fine in such a mold.

It seems that these molds were one offs anyway, ie cast a big wad of buckles and break the mold (if I interpret the archeological evidence correctly)

The key seems to be making sure the clay is dry dry dry before casting. Any baking or firing could potentially change the mold so that it wouldn’t give as good of detail, etc…I’m not sure how they addressed that in period.

Master Mark might know more…he’s done a pretty extensive study of all the extant molds he could find in the Museum of London, etc?

--AM

 

From: Fvigil at aol.com

Date: July 28, 2008 4:33:02 PM CDT

To: pewterersguild at yahoogroups.com

Subject: Re: [pewterersguild] Yay!

 

stefanlirous at austin.rr.com writes:

>Hmmm. Something just occurred to me. Doesn't everyone use a spring

>clamp to hold their two pieces together?

 

Never. I simply hold mine together in my (well gloved) hand. If the blocks are flattened/aligned right its never a problem - theres no leaks or anything. Putting a clamp or two on a mold would slow me down so far it would drive me nuts.  When things are going well I can get 10-12 casts in a minute - even with 3 part molds. Using a clamp I'm guessing that would drop to 2-3. I use a pair of welding gloves to protect my hand, so even if there was a spill it would not hurt me.

With most molds, the metal is cool enough to open the mold almost instantly. In fact with a lot of them I pour the metal in the mold, and almost immediately dump the excess (still molten) part out of the sprue and back into the pot. Then I open the mold with no additional delay.

The only time I use clamps is when I am originally adding registration pins to the mold and I want to make sure its held together extra tight with no chance of slipping.

Fernando

PS By the way, if you'll be at Pennsic, feel free to stop by Calontir's camp and I can show you some of the registration pins discussed previously. Or we'll be doing an A&S exhibition in the road in the middle of the merchant area on Thu and Fri from 2-5. I'll be casting there and you can check out my methods if you like. Pictures and descriptions of the Exhibition from previous years can be found at: http://www.james-gang.org/CPAS/CPAS.php

 

 

From: Anne-Marie Rousseau <dailleurs at liripipe.com>

Date: July 28, 2008 4:54:14 PM CDT

To: <pewterersguild at yahoogroups.com>, Stefan li Rous, <stefanlirous at austin.rr.com>

 

on using spring clamps, etc

 

I think its important to put my experience into a bit of context...I learned how to make a mold and cast in pewter from Mark de Gaukler at a non-sca re-enactment event, and actually most of my casting experience has been at same. we were tehrefore constrained to use only those tools and methods and materials that would have been available in medieval western europe to a middle class craftsman. to that end, we didn't use a lot of tools per se, but instead used a lot of found objects and "hey, this would make a dent in soapstone"! kind of things :)

 

spring clamps? nah. just hold onto the mold good and tight. register pins will help with this in a period appropriate way. wrap a bit of leather around it if you're worried about splashing on your hand (better yet, learn not to overpour), and it will protect against the mold getting too hot to hold as well.

 

that said, I'm fully aware that my experience is by far in the minority. most folks have no problem at all applying modern solutions to their problems, and that's cool too :)

 

one of my favorite things about this list is that we can all see that no matter how we choose to tackle our problems, we all have the same problems :)

 

--AM

 

 

From: Brian Ferguson <bjf10 at the-immortals.com>

Date: July 28, 2008 9:40:58 PM CDT

To: pewterersguild at yahoogroups.com

Subject: Re: [pewterersguild] Yay!

 

> Hmmm. Something just occurred to me. Doesn't everyone use a spring


> clamp to hold their two pieces together? 



 

I've experimented with a variety of solutions. Personally, I found that 
spring clamps slowed me down too much.



 

For molds with register pins, I usually just hold the mold in a gloved 
hand. I've used welding gloves, and even simple gardening gloves (it 
depends on how many thingies I'm casting at one go.) Alignment is taken 
care of by the pins, with a bit of cost in casting speed. Eventually 
the mold will be too hot to hold, and I cool it down by placing it on my 
anvil. It cools down to room temperature within a few minutes.

 



For molds without register pins, I've found that a simple jig works 
quite well. I use several blocks of steel to build a frame around the 
mold, and apply pressure on one of the blocks to hold it shut while I 
pour. The main advantage of this is that I can keep casting 
indefinitely, no matter how hot the mold gets, as I virtually never 
touch it. The disadvantage is that it can be a bit tricky to get the 
setup working well, especially for molds where alignment matters. 
Overall I think it's the fastest method, for me.

 



A jig can be used for molds with register pins too, if you have to cast 
a *lot* in a relatively short timeframe.



 

-Derian.

 

 

From: Fvigil at aol.com

Date: July 29, 2008 5:14:06 PM CDT

To: pewterersguild at yahoogroups.com

Subject: Re: [pewterersguild] When doing two sides...

 

My preferred method is this:

First registered your two stones (either with pins, by cutting the stones to match, or at least marking the stones)

Next carve the front of the mold, and carve the sprue into both stones.

Now you can do a test cast of the front half of mold, and after you open your mold you can carefully place the casting onto the back stone.  It will be aligned perfectly on this stone by the part of the sprue you carved into it.

Now you can carefully trace around the casting, and when you remove it you'll know exactly where to carve on the back piece for perfect alignment.

Make sense?

Fernando

Calontir

 

 

Date: August 11, 2008 10:13:55 AM CDT

To: pewterersguild at yahoogroups.com

Subject: Re: [pewterersguild] Historical reference books?

Reply-To: pewterersguild at yahoogroups.com

 

sean.wales at comcast.net suggested::

<<< Pilgrim Souvenirs and Secular Badges

Medieval Finds from Excavations in London

Salisbury & South Wiltshire Museum

Pilgrim Souvenirs and Secular Badges

Heilig En Profann 2

Musee National du Moyen Age-Thermes de Cluny

Enseignes de Pelerinage et Enseignes Profanes >>>

 

 

I'm just getting home from Pennsic so I'm a bit behind here.

If you are interested in pilgrimage badges, I highly recommend the first two books Sean mentioned. These are both by Brian Spencer, who was widely regarded as the foremost authority on pilgrimage badges.

Here are a few more suggestions for resource books:

  

* Dress Accessories, c.1150-c.1450

  (Medieval Finds from Excavations in London)

  - Geoff Egan and Francis Pritchard

This is from the same collection as the first suggestion above. It covers things like buckles, buttons, belt mounts and brooches and is a pretty nice resource. It used to run about $100, but was finally reprinted and the price dropped to around $50. Amazon occasionally has it at pretty big discounts.

[Side note: The entire Medieval Finds from Excavations in London series (put out by the Museum of London) is pretty awesome. The series includes not only the two previous books, but books on Knives and Scabbards, Horse Equipment, Textiles, and possibly others. These are all great resources if you are interested in their fields.]

 

* Medieval Pilgrim and Secular Badges

  - Michael Mitchiner

This is sort of a neat book in that it shows most badges at about double size which is nice for seeing the details. Its organized sort of by time frame which makes looking for things more difficult but its a great flip through for ideas book. I'm not sure if it is available here, but it can be purchased from Amazon UK for 30 pounds.  Its also often on E-bay, but you have to be careful. Some of the buy-it-now auctions have it listed for $90 or more, and other auctions for it appear cheap, but have huge shipping fee to trick the unwary (I've seen up to $39 for the shipping alone on this). But I've also bought two copies for about $40-45 (including shipping)

* Heilig en Profaan:

  Laatmiddeleeuwse Insignes uit de Collectie H.J.E. van Beuningen

    

Sean recommended volume 2 of the series, but volume one is pretty nice too. These two are from the Netherlands. The first has something like 1000 badges, and the second over 1200.  The books include a number of conference papers  - unfortunately, the books with the exception of one or two of the papers are in Dutch. These were $100 and $120 when I bought them through Windrose Armory

[Another Side note: It's worth mentioning here that the Musee de Cluny book Sean mentioned is in French and unfortunately this sells for something like $150 last time I saw it for sale].

Fernando

 

 

From: bjf10 at the-immortals.com

Date: August 13, 2008 9:38:02 AM CDT

To: pewterersguild at yahoogroups.com

Subject: Re: [pewterersguild] Historical reference books?

Reply-To: pewterersguild at yahoogroups.com

 

Here's a few neat online sources with tons of photos of extant badges:



http://www.let.kun.nl/ckd/kunera/index.php?lang=uk&#8232;


 

http://talbotsfineaccessories.com/cgi-bin/Strong_Collection.cgi&#8232;


 

-Derian.


 

<the end>



Formatting copyright © Mark S. Harris (THLord Stefan li Rous).
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