Ok man will ya' share? What did you use for mold material and what glass did you cast? Are we looking at frit layering? What size frit(s)? Did you use fusers glue?
I'm not much for documentation, but I'll try to quote from memory. Memory serves, of course, but in a halting and surly manner.
Mold material: Good ol'fashioned potter's plaster and silica flour (325 mesh). That's all. I slaked the splash coat for a good 5 minutes, then applied about 1/8 - 1/4 thickness to the wax piece. I then covered the piece in what I call a "pond scum mummy wrap", which is basically tufts of fiberglass mesh torn from a roll and soaked in half-and-half plaster/silica and then wrapped over the splash-coat. Again, about a 1/8 - 1/4 inch thickness. I then invested the piece in a coddle mold about an inch thickness, with half-and-half plaster/ silica.
I've only anecdotal evidence that the mummy wrap does any good. Most of the time the piece comes out with nary a crack, but sometimes I get cracks. It may be superstition. Plus, it is much harder to deinvest the piece with the mummy wrap on. I soak it in water and carefully take chunks out with dental tools. A PITA.
After steaming out, I lined the mold in kind of a slip-cast fashion with a watered-down mixture of CMC (carboxymethylcellulose) gum and Bullseye powdered glass. The "horns", "violations", what have you, where the eyes, ears, and mouth are were black powder which I applied with those glaze squeeze bulbs that have long tubes (don't know the technical name for 'em). I kept adding and smooshing the powder into the "horns" until no more could be added. Don't ask what proportions of colors for the rest of the piece, because I don't keep track. I remember the face and hands were roughly equal parts pink and white, but the "base"color contained some blue and black powder in the scrap, so it all went kind of purple on me.
It took about an hour for all the colors (the black "horns" and three slightly-more-red pink applications on top of each other in slip-cast fashion) to dry out (i.e., for the water to either evaporate or wick into the mold), and the mold was ready put in the kiln. The slip-cast color layers ended up being about 1/4 in thickness on the face. I put the mold in the kiln at 200F for 24 hours, but obviously that was not long enough for the mold to dry out as I got cracks anyway. Again, superstition and dumb luck heavily invoked. The slip-cast colors end up being hard to the touch (fingernail will scratch it off, but it is not powdery).
The "base" glass was scrap I had lying around and busted up with a hammer. Some parts clear Bullseye, other parts Bullseye with all different sorts of color in it - mostly blues and black. The frit busted into pieces ranging from dust to about 1/2 inch in size. I put some frit into the mold level to the top of the piece and the rest was placed in a drip crucible suspended about 2 inches above the mold. I was worried that the crucible frit would melt before the mold frit and glass would spill over, but such was not the case. Probably because the crucible was placed so close to the mold. I use an old jewelry dewax kiln which has about 18 inch height to play with inside.
I used the firing schedule in Halem's book for casting and took it to 1650F to soak for about 4 hours. Sometimes I soak for 8 hours depending upon how intricate the piece is. I may be overdoing the temp and soak time, but it works for me.
That's my story and I'm sticking with it.
