I decided to modify the kiln firing schedule for the two large beaver panels- adding another hour to the first segment, slowing it down between a couple of critical temperature points, and then adding a couple of cool-down segments that will slow that down from 1600 to 950 degrees as it passes thru a critical temperature in the 1100 range.
I didn’t add a slow down before now, when the kiln shut off it shut off and cooled, and 2000 degrees cools pretty fast with the power off, so now when it reaches 1600 the heat will turn back on to slow it to 175 degrees drop an hour down to 950 when it shuts off, that will help avoid potential problems from cooling these heavy pieces too fast.
All added up it looks like the estimated time now will go from 24-26 hours to about 32 hours, so if I switch it on at 2pm on Friday it should shut off around 10pm Saturday.
Actually, I think I’ll turn it on to-morrow at 7AM instead
Turned on this morning (Thursday) at 7:10, it’s started it’s inexorable temperature climb from 195º around 6 pm to 2,070º by to-morrow afternoon, so it will be slowly increasing all night into to-morrow. I won’t be able to open it until Saturday late afternoon to see if both beaver panels made it, though as soon as it hits about 1,000º I should be able to at least see the tops of the panels through the upper peep hole, if I can see them through the peephole then they are still standing and didn’t explode, so that will at least be a preview of sorts
Right now @ 272º it’s above the boiling point of water, so the sculptures would be steaming off any moisture, at this stage the programmed segment has a temperature rise of 50º an hour to 300º. It was 80 or 100º previously and all went fine, but I decided to slow it down to be safe even though it adds a couple more hours time.
Looks like the kiln shut down around noon, it was on the cooldown from 2,070º when I checked at 12:30 and it was 2,015º. Now it’s still idling according to the programming I did- until it hits 1,600º and then it will provide enough heat to keep the cooling rate to 175º an hour down to 950º when it shuts off. The first hour it started cooling down it went down 250º, the higher the temperature the faster it’s lost per hour when the heating elements shut off, but that rate per hour falls as the temperature drops.
Probably by the time it’s 1,600º it may naturally only fall 175º/hour or less and not even need the elements turning on, we’ll see.