slumping failure. Why????

Riverglass · Post by **Riverglass** » Thu Aug 14, 2003 4:52 pm

I was making a mask out of Bullseye. Fused too layers of glass with assorted decorative pieces on top. Fused nicely, annealed for 30 minutes. Used Paragon kiln. When I went to slump it over a wall sconce mold I had purchased at BEye, it cracked in two at approximately 340 degrees. I was slumping at 300/per hour.
Any idea why it split in two? I had a piece of clear/black streaky in the middle of the bottom layer. Any advice/thoughts will be greatly appreciated. Thx - km

Brock · Post by **Brock** » Thu Aug 14, 2003 4:57 pm

Thermal shock. Slow down on slump firings. Brock

Barbara Muth · Post by **Barbara Muth** » Thu Aug 14, 2003 6:58 pm

try the same piece at 150 per hour or even slower if your surface is uneven. That should solve it.

Been there.

Barbara