One more question, sorry, on slumping my first bowl!

[Jeri]

I'm sorry I forgot to add this on the last question! This is my first bowl..15.75" and 2 full pieces thick and 3 counting the center accent circle, Bullseye glass. I am now going to slump it in the mold and wondered what would be the proper settings for the kiln for this size piece. I have a Skutt 1414 with the electronic controller which has some of the programs preprogramed. There are options of slow, med, fast and the presets are taking it to 1220 and holding for 5 minutes. I can program it myself if that would be the better option? Thanks again for any help offered! Jeri

[Lisa Allen]

For a piece that size, my slump schedule would be:

250dph to 1150, hold 20 minutes
9999dph to 960, hold 2 hrs
60 dph to 750, no hold

Your pre programmed sch would probably work fine. I am not sure what temps are associated with slow, med and fast in your kiln, but I would choose a ramp that doesn't go more than about 300dph up to your top temp.

Lisa

[Marty]

For 3/8" thickness I'd slow down to at most 150F dph on the way up. I slump at 1240 and hold for 30 to 45 min, but I'm working 1/2" thick. How fast does your kiln lose heat from 960 down? You might just be able to shut it after a 2 hr. anneal soak at 960.

BTW I used to break speed limits on the way up (slumping) but have seen the (cracked) error of my ways.

I don't like the preprogrammed thingie- it limits you. Get to know what your kiln does and write your own.