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^6 firing schedule for reduction

updated mon 5 aug 02


Marcia Selsor on sun 4 aug 02

Dear Charles,
I fired two kilns for 20 years to ^6 was a 36 cubic foot
sprung arch and the other was a
60+ cubic foot car kiln. I designed and built both of them with the
exception of the oversized venturi burners which the
facilty services installed without my input. There were two burners
coming in the rear.
The kilns were well insulated with soft brick and fiber.
The body reduction was done when ^010 was starting to go. It still
climbed in this reduction and evened out. It came out of
reduction at ^04. If trying for reds the was a border line reduction
flame up to when ^5 was down. Then a 45 minute
reduction and holding around ^6 until flat usually about 45 minutes to
an hour. We got copper reds, nice celedons, tenmoku,
iron reds, and nice stontware looking glazes.
I dropped the temp of the finrings in 1979 when we moved into new
facilities and was required to get the firing schedule
within an 8 hour shift for my assistant. The assistant was cut soon
after but the schedule remained the same.
You can email me directly if you have further questions. These kilns
fired so easily I had marks on the damper shelf and
could fire blind folded time an again. These kilns were the two major
kilns for the ceramics program at MSUB for about
60 students . They were fired several times each per week once we got
going into the semester. I never used an oxyprobe but
held a stick in the peep hole. If it didn't burn, I called it reduction.
Purple green flames also indicate but
sometimes the natural gas is richer than other times so this was the
Marcia in Montana