I *thought* I was going to make the next version of Sky Blossoms this week, and prepared a nice frame and background for it. The background is a single flat piece of bright white glass. The frame is made of two layers of black glass strips, with miter joints at the corner. I don’t like making miter joints with glass any more than I do with wood, as I find it very difficult to cut perfect 45º angles.
I assembled the pieces in the kiln and programmed the firing schedule. The next morning, I found the white background had cracked and separated as the temperature was rising, but the black frame pieces seemed to have been undisturbed by that and they melted beautifully, holding the whole thing together. What happened was that I set the temperature to rise too fast. The middle of the white piece expanded as it heated up, but its edges were protected from the heat by the black pieces and by the ceramic dams around the assembly. The cooler edges (relatively speaking, since this probably happened around 1000°) weren’t expanding fast enough to keep up, so it ruptured.
What to do? My first idea was to fill in the crack with small pieces of matching white glass and fire it hard in hopes of getting it to melt smooth. Then I realized that this is a fantastic opportunity to do something interesting. I’ll write again after I smooth the edges of the frame on my lap wheel and start working on the new design.
ps: Shattered Illusions is a friend’s business name. I’ve always liked it, but can’t claim to be that clever.