Firing 96 and 90 in the same firing

[Jenna]

Hi All,
I seem to remember someone mentioning they fire bullseye and uruborus in the same firing but can't find the thread. Is this possible and if so, how do you anneal for this? One stop at bullseye annealing temp, another at 96 temp? A hybrid temp? How about the full fuse temp? Just soak longer to give the bullseye more heat time?
Just for clarity, I am not combining these glasses, they will be side by side in their own molds.
Cheers, Jen

[Stephen Richard]

Yes you can fire both S96 and Bullseye in the same firing. At a fuse temperature of 800ºC, the S96 will be flatter than Bullseye. Sounds to me like you are doing a slump (moulds), so there should not be a problem.
The annealing soak at the annealing point is a temperature equalisation measure, so you can soak at 516ºC (30 mins for 6mm) and then at 80ºC per hour down to 370ºC and then faster to room temperature.

[Bert Weiss]

In general, differences will show up more in the amount of heatwork you get with different colors or manufacturers, on the same heatup schedule. The annealing characteristics are close enough that you can anneal them all the same.