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Hello fellow artists -
I am getting to know my new kiln and Sentry controller. The CS-26 has no peep holes or vents. When I program to cool AFAP from my peak temperature down to annealing temp, the kiln takes too long (a couple hours) and on darker glasses there is a hint of devit. I've tried propping the front of the lid up on 1/2 inch firebrick, which helps some. I don't want to heat shock my work. Please advise - what's the right approach with this type of clamshell kiln? (The kiln shelf is about 2 feet by 2 feet, so it seems I'll have some variability front to back with the propping technique). Many thanks!

speed kills.
If you want to load a kiln sooner than the one you have wants to cool down the answer is to buy another kiln.
There are no shortcuts to glass making.
You would not want to sell a piece and have it break months later because you didn't anneal it.

I'm wondering what type of kiln you were using before this, that the cooling cycle was substantially shorter.

If you are using a corderiete (feels like clay, heavy, hard) shelf, you could try a ceramic fiber board one to cut the time on flat work. Fiber board cuts away probably 20 lbs on a shelf that size, so less thermal mass. But really, won't cut much time at that point. Maybe 45-60 minutes shorter before it hits anneal temp. Takes nothing off anneal.

Its moving from a very small Paragon manual front loader (< 1 ft x 1 ft inside) to a Paragon clamshell with about 2 ft x 2 ft and an Sentry 2.0 controller. I'm using a kiln shelf from Bullseye on 1" posts. I think the heat mass is so much larger than my little starter kiln perhaps my expectations need adjustment. Or I need some context. I work with COE 96 glass. If the cooling profile from 1465 to 950 takes 2.5 or 3 hours with this kiln, is that going to work out or will I see devitrification? I have no concerns about a run taking a full 24 hours if that's what it needs, but I don't want to have quality issues based on the cooling rate.

TammyP wrote: If the cooling profile from 1465 to 950 takes 2.5 or 3 hours with this kiln, is that going to work out or will I see devitrification?

That's an entirely normal cooling rate. No need to crash cool. If you get devitrification it's more likely due to other factors than how rapidly you cool through this segment.

TammyP wrote:Its moving from a very small Paragon manual front loader (< 1 ft x 1 ft inside) to a Paragon clamshell with about 2 ft x 2 ft and an Sentry 2.0 controller. I'm using a kiln shelf from Bullseye on 1" posts. I think the heat mass is so much larger than my little starter kiln perhaps my expectations need adjustment. Or I need some context. I work with COE 96 glass. If the cooling profile from 1465 to 950 takes 2.5 or 3 hours with this kiln, is that going to work out or will I see devitrification? I have no concerns about a run taking a full 24 hours if that's what it needs, but I don't want to have quality issues based on the cooling rate.

Agreed with Brad - it's not like you are hanging out up there at 1465 for any longer in the big kiln. The top temp falls off rapidly for the first 100 degrees. Big kiln, big shelf, big(ger) pieces - 24 hrs. isn't particularly long.

Congrats on the new kiln!

Thanks gents! This is an exciting and slightly daunting time - I have a steep learning curve, and am SO ready to get on to bigger pieces and less time walking and to and from the kiln throughout a run!

-- Tammy