Wonder what I am doing wrong. I was trying to slump a single layer 2 to 3mm peice of Bullseye Confetti glass. This has not been tested for compatibility but I have fused it and slumped it in the past. This has happened to me a 3 times, with different glass but always the same mold and always the same kind of break (only has happened with CoE untested glass). I thought you could slump just about any glass!
The mold is 8 inches across and is square. I was ramping up at 580 per hour to 1320, coming down the same and annealing at 960 for 30 minutes. Is that too fast? The break is always a single break, about 1/3 of the way across, and is curvy.
I never reach a full slump before I find that it has broken. This last time the kiln was at about 1200 when I peeked and it was already broke.
Karon
Another bowl bites the dust!
Moderators: Brad Walker, Tony Smith
Re: Another bowl bites the dust!
Thermal shock. Slow down to 300 DPH or less, and you should be fine. You don't even have to go as hot as 1320, try 1150-1200. Brockkbarbour wrote:Wonder what I am doing wrong. I was trying to slump a single layer 2 to 3mm peice of Bullseye Confetti glass. This has not been tested for compatibility but I have fused it and slumped it in the past. This has happened to me a 3 times, with different glass but always the same mold and always the same kind of break (only has happened with CoE untested glass). I thought you could slump just about any glass!
The mold is 8 inches across and is square. I was ramping up at 580 per hour to 1320, coming down the same and annealing at 960 for 30 minutes. Is that too fast? The break is always a single break, about 1/3 of the way across, and is curvy.
I never reach a full slump before I find that it has broken. This last time the kiln was at about 1200 when I peeked and it was already broke.
Karon
My memory is so good, I can't remember the last time I forgot something . . .
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