Alrighty!
So, after some small mix of guesswork combined with light testing, it proved that my suspicions re: plaster/cement were correct. Both mediums prefer to crumble rather than crack, with the plaster being susceptible to powdering entirely.
Slate's propensity for fragility turned out to be the ultimate undoing of that medium's potential for use in the project. It cannot be acquired at all to be thin enough so as to be usable.
I made the decision to incorporate actual stone tiles into the project. I was really hoping that plaster would work, because it is very light, but the stone won't make the finished piece too heavy, altogether. I'm expecting a total weight of anywhere between 10 and 15 lbs, not that I'm using stone.
I lucked upon some good, grey, stone tiles that are measured at 8'' x 8'', which is the size of a Mage Wars board tile.
The base of the piece is 1/4'' sanded birch. Pine would have been preferred, as Pine is a slightly more durable wood, but the birch is significantly lighter, and cuts more cleanly than Pine, and once sealed and lacquered it should more than do the job.
The frame of the piece is comprised of 1'' x 1 1/2'' pine boards.
The measurements are as follows:
Base of 1/4" soft, sanded Birch: 27" x 35": (later to be cut in-half across the 35" dimension, see below)
As the 1 1/2" x 1" pine boards will be sitting broad-side upon the base, and the tiles measure at 8" x 8" the base needed an extra 3" above the surface area of the tiles on both sides.
2 pine boards at dimensions of 1 1/2" x 1" cut @ 35" (later to be cut in-half, see below)
2 pine boards at dimensions of 1 1/2" x 1" cut @ 24" (2 feet)
The two longer pine boards lay the length of the birch base, while the two shorter pine boards lay at a 90° to the other two boards between them.
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Because I want the finished piece to fold inward upon itself, once everything has been measured, the longer pine boards will be cut in-half, as will the birch base along the 35" dimension. Two 1 1/2" brass hinges will be employed to hold the unit together prior to gluing/mortaring of the stone tiles. Once cut, the frame will be wood-glued to the base, and clamped overnight, prior to stapling at the corners/edges, and finally, some 1/2" wood screws, 2 at each corner joint, then finally, hinged together.
GLUING THE TILES
Once the entire base is prepared (cutting, gluing, screws/staples, hinges), I will begin the process of laying a fastening facilitator to the interior base of the piece. For this purpose I have chosen to implement some self-adhesive cement board tape. The concept here is that the board tape is a mesh medium that will act as an intermediary between the tiles and the birch base. Once laid, the tiles will be placed on top of the mesh, and here's where the fun begins:
A grid will be prepared to lay uniformly between each of the tiles and the frame. The grid will be comprised of scrap wood left over from the original cutting from the larger birch board which is now comprising the base/frame of the piece. This grid will ensure that when the tiles are cracked the framework (the separations between the zones) will not be compromised. Essentially, each individual "zone" (tile) will be cordoned off from the others, as well as the frame, by a very thin strip of wood.
The tiles will be cracked using a point-chisel and ball-peen hammer. Once the cracks are to my satisfaction, a solution comprised of 50% elmer's all-purpose glue and 50% water will be "poured" over each tile. The dilution of the water will allow the solution to permeate between each individual crack and crevice in the tiles. Now this is why the cement board tape was applied: When the solution is poured, the cement board tape will be raising each tile just a fraction of a millimeter from the birch base. The liquid solution will well BELOW the tiles, through the mesh of the board tape, and, when hardened, the tiles will be attached to the base through the tape onto the birch base. The solution will be applied only so that it is approximately half as deep as the height of the tiles, so approximately 1/8" to 1/4" deep. This will sit for a few days, at least. I may heat-treat the whole piece in the sun provided I get a particularly sunny day. Otherwise, I am prepared to leave it alone for 4-5 days untouched.
Once the glue solution is dried to satisfaction, I will apply a white unsanded grout that has been mixed with black ink to provide the desired color. The frame separating the zones will be removed, and this grout spread across the entire interior of the frame, over the tile work, to provide the color and hard-surface cover for the cracked tiles, as well as providing the interior holding agent between the tiles.
That is the bulk of the project. Other details to follow. Here are some pictures:
-nihil
