low fire clay molds
I have fired some clay molds that were 1/8″ to 1/4″ thick and they work beautifully! I let them dry for several days to make sure there’s no moisture left and then fire them at R250 to 500, hold 0, R AFAP to 1800, hold 0 (off). This took about 4-1/2 hours. 3 coats of kiln wash and then I used my fire polish program to slump single thickness of glass. (These molds are less than 5″ dia.) Worked great!