slumping temp for float glass

Linda Hassur · Post by **Linda Hassur** » Fri Jan 16, 2004 3:30 pm

I tried to slump a very small bowl yesterday along with a couple more molds that I was using to slump. The other two completed their slumping (one with BE clear and the other float) but the small bowl never did hit the bottom of the mold. I started at 1250 and continued rising the temp in small increments until I hit 1325. I decided at this point that it wasn't going to totally slump. Any ideas? Thanks Linda

charlie · Post by **charlie** » Fri Jan 16, 2004 3:35 pm

the smaller in diameter it is, the longer and higher you have to go. you need a certain amount of weight of unsupported glass in the middle to make it bend. the less this is, the more heat and/or time you have to provide.

Judy Schnabel · Post by **Judy Schnabel** » Fri Jan 16, 2004 3:49 pm

Linda,

Personally, I would not try to slump float and BE or Spectrum in the same firing. It takes higher temperatures to slump float than BE or Spectrum.

Was the slump that didn't quite make it float?

Judy

Linda Hassur · Post by **Linda Hassur** » Fri Jan 16, 2004 5:55 pm

yes, it was the float that didn't slump enough. How high do you usually have to go to get float to slump into a small mold? Thanks Linda

Judy Schnabel · Post by **Judy Schnabel** » Fri Jan 16, 2004 7:01 pm

Linda,

I'm not looking at my records at the moment, but I slump Spectrum around 1100 and when I do a drop mold with float I fire to over 1400. If I were slumping float into a more shallow mold, I'd go to about 1200 or so.

Judy

Bert Weiss · Post by **Bert Weiss** » Fri Jan 16, 2004 7:11 pm

I'd probably go to 1300 - 1350 depending on how fast I wanted it to happen.