Mark C: Could you elaborate please? I do glass in a kiln and stainless steel molds are commonplace, used to about 1350f for slumping glass. However, I want to try something new, using a stainless steel shelf in the kiln, with Bullseye thinfire or some other protection on the stainless. I would probably like to fire this to a minimum of 1500f, maybe as high as 1800f. The reason for doing this is that I want to have a really smooth bottom on the work. Because kiln wash or thinfire conforms to the shelf, which is always less than perfectly flat, I have not been able to achieve this so far. Any info appreciated, thanks!