Thursday, 22 April 2010

Pot Melt Schedule

I usually use a schedule like this for either S96 or Bullseye:

100C/hr to 220C for 20 minutes; this is approximately the crystobalite inversion temperature – to be kind to the pot
220C/hr to 570C for 20 minutes; this is approximately the quartz inversion temperature – again to be kind to the pot
220C/hr to 677 for 30 minutes; this is a bubble squeeze temperature to allow larger bubbles to escape from the pot before melting begins.
330C/hr to 850C for 120 minutes; this is to ensure there is plenty of time to empty pot
AFAP to 805C for 30 minutes; this is to allow thickness equalization and also to allow bubbles to pop and seal.
AFAP to 482 for 90 minutes; this is for Bullseye, but is applicable to other glasses too.
55C/hr to 427C no soak;
99C/hr to 370C no soak;
120C/hr to 150 end;
Allow to cool to room temperature