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. ************************************************************************ 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 ************************************************************************ 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", 30.00 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 12.00 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. 12.95 *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/ ( (-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 ( ( http://talbotsfineaccessories.com/cgi-bin/Strong_Collection.cgi ( ( -Derian. ( <the end> Edited by Mark S. Harris casting-msg Page 23 of 74