Working-Slate-art - 10/22/07
"Working with Slate" by Master Sven Odin Eye.
This article was submitted to me by the author for inclusion in this set of files, called Stefan's Florilegium.
These files are available on the Internet at: http://www.florilegium.org
Copyright to the contents of this file remains with the author or translator.
While the author will likely give permission for this work to be reprinted in SCA type publications, please check with the author first or check for any permissions granted at the end of this file.
Mark S. Harris...AKA:..Stefan li Rous
stefan at florilegium.org
This is the text to an Ithra class I have taught 3 or 4 times but no longer teach, it's too bloody hard for me to pack all that slate for the students!
Working with Slate
by Master Sven Odin Eye
In period they used a type of bow saw (like the 'modern' bucksaw) without teeth on the blade. They kept it lubricated with water and the stone itself provided the abrasive for cutting. Needless to say, this was a very slow and laborious process.
I use a regular handsaw like you use on wood. I bought a used inexpensive modern saw at a swap meet for $2.00. I cut the stone same as I would wood, just slower. The blade is holding up remarkably well. I expect it to still work fairly well with duller teeth and eventually I'll try to re-sharpen the teeth with a hand file (I've had mixed results with this in the past, blade sharpening is a science in itself).
The cutting is best done as a two person job, as you need someone to support the stone as you cut it off, otherwise it would break off the corners. Try it and you'll quickly see exactly what I mean.
The plain sawn edge looks too plain and manufactured. A course file works well for rounding off the sharp edges, but what really dresses it up is a bit of hammer work. Tap around the edge, fairly firmly, but it is safe to start out light and increase the force of your blows. This hammering will give the piece a bit of a chamfered and scalloped edge that is quite decorative and very period. Be careful at the corners, they want to chip off more than you'd like. This is where it helps to really round off the corner with a file before hitting it with the hammer. This keeps the forces from being too concentrated. Be prepared for big pieces to come off the back side at the corners sometimes. Also, a larger sliver may come off the front than you planned, it will be shallow and it won't cause you any problems, as long as you remember to chip the edge before you do your design.
You can easily drill slate so it can be hung from a leather thong as a type of sign or stone reliquary or some such. In period they actually drilled slate plates for wooden pegs when using the slate for such things as church and castle roof shingles.
I actually made a bow drill, with a hand hammered drill bit, that works quite well. I have also used the old fashioned hand powered 'egg beater' type of hand drill. If you are more interested in the end result than recreating laborious drilling methods, you'll find it's quite easy to drill with an electric drill and modern bits. Just take it easy, try to force the bit through too fast and you can break the slate.
I took a piece of antler, drove a nail into each end, cut the head off and sharpened the stubs with a file. I used this tool to scribe designs in the slate. You scratch it lightly to lay out your design. Then you scratch it over and over, deeper and deeper, to finish the design. Make a wrong scratch, use a knife and scrape the gouge out, rub it with the heel of your hand (or a pink pearl rubber eraser) and it blends in with the rest of the stone. This is much like the period scrape & burnish method of correcting mistakes on velum with ink.
This stone has what I call 'direction of lay' almost like the grain in wood. First it is in layers, and then each layer has a direction of lay. This means that the tool will want to follow the grain sometimes more than your scratched line. Once you gave gotten a groove started then it's fairly easy to scribe vigorously along it deepening it. Because the stone is in layers, if you try to gouge out too much at one time you can cause fairly large areas to flake off. When I'm doing small diameter circles I'm particularly careful as the center wants to delaminate and pop right out.
I've just started to experiment with this. A really famous runestone/Celtic cross with carved Viking warrior is carved in slate. I've included an illustration of it on another page. So I tried it some. It carves fairly well with a good sharp chisel, not as cleanly as wood as you can imagine, but with a bit of practice I think one could turn out some exceptional art work with this stone. I've shown my work at a couple of local events. One man took my experiments a step further. He split the slate to a thin piece, carved in his design and then painted the background, it really looked great.
Sources of Slate
Decorative Rock outfits have the big stuff (this is not cheap) I've purchased some there, it's a real shock to the pocket book. But you only need this source for the really big and awesome projects.
The best source is your local home improvement store (Supply One, Home Depot, etc.). Here I've found 12"x12" square floor 'tiles' running 1/4" to 3/8" thick or so, for less than $3.00 each. Pick through them a bit and you can come up with some decent carving stock.
You can also find small panels in squares and oval shapes, with the holes already drilled in them and hung on a leather thong, at most of the large craft stores. A bit pricier and only available in small sizes but quite nice looking and an easy piece to start with.
Tips & Hints
One thing I've discovered with most SCA era crafts, read up as much as you can, then just dive in and do it, learn from your many mistakes and you will find that much which was clouded in mystery becomes crystal clear. There is no failure where something has been learned from a 'mistake', that's how most of the world's accumulated wisdom arose in the first place! Have faith in yourself and enjoy the 'doing' of each project.
Copyright 2007 by Master Sven Odin-Eye, 1044 NE Sunrise Ln., Hillsboro, OR 97124. <wdlndbks at aol.com>. Permission is granted for republication in SCA-related publications, provided the author is credited. Addresses change, but a reasonable attempt should be made to ensure that the author receives a copy.
If this article is reprinted in a publication, I would appreciate a notice in the publication that you found this article in the Florilegium. I would also appreciate an email to myself, so that I can track which articles are being reprinted. Thanks. -Stefan.