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how to get pit hotter?

updated wed 15 oct 03


Judy Nelson-Moore on mon 13 oct 03

We just did a pit firing in a newly dug pit. It is about 4-5 feet deep, 10
feet long, 8 feet wide. We didn't get it hot enough. Any suggestions for
getting the temperature up higher?

Judy Nelson-Moore

William Lucius on tue 14 oct 03

You have posed an interesting question, and based on the limited information
provided, I would suggest that the pit may be too deep. Although it is
possible to "draw" air down into a pit, it has been my experience anything
over a foot or so deep usually suffers from impeded air flow, resulting in a
cool firing. If for some reason your pit has to be that deep, then consider
making it wider so that the air can get to the fuel.

Knowing the past is a good antidote for constantly "reinventing the wheel".
Ancestral Pueblo pit kilns are relatively shallow and were capable of
reaching temperatures approaching 900 degrees C. The potters used small
diameter juniper for fuel (which burns hot and clean) and apparently sited
their pit kilns to take advantage of the wind to boost firing temperatures.
They also consistently preheated their pots and pits with a significant
amount of fuel, which left a layer of charcoal that would reignite when the
fuel placed over and around the pot was fully engaged, effectively "ramping
up" the temperature.

I hope that this helps.

William A. Lucius, Board President
Institute for Archaeological Ceramic Research
845 Hartford Drive
Boulder, CO 80305

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