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tall kiln for tall ware

updated wed 20 jan 99


cyberscape on tue 19 jan 99

I used to make and fire a lot of really big sculpture, 7 feet tall and
taller. I would build the pieces right on a brick pad, two courses
thick. Then after the piece was dry (several weeks), we would build a
soft brick kiln around the piece, leaving several burner ports around
the bottom and making spyhole ports that were their own cone shelves by
extending the brick on the bottom of the port into the kiln about 3
inches. When the walls were taller than the piece, we would cover the
top with either kaowool pinned to metal lathe or softbricks with a 3/4
inch hole drilled in the middle threaded onto steel rods and spanning
the walls. We fired with gas, very slowly, often for 2-3 days. After
firing, we just took down the kiln. It was not a big deal and always
worked great. Just leave a reasonable hole in the top center and use a
kiln shelf or insulating fiberboard as an updraft damper. Even out the
firing by making the flame cleaner and hotter at the bottom, or opening
the damper more to pull the heat up. If it starts to get really uneven,
close the damper more, put the kiln in a mild reduction and let it even
up as it's climb stalls. Giving credit where it is due, I learned this
from Ron Brown when I was in graduate school. Ron has a piece in
Rhodes' kiln book, with a kiln being built around it.

When I was teaching at the Canberra Art Institute in Australia in 1991
we built tall kilns out of concrete reinforcing wire mesh bent into
cubes wider than the piece with neither top nor bottom, and pinned
ceramic fiber to the inside with Kanthal element wire. We built the
brick floor, built the piece on the bricks and stacked the cubes up
higher than the piece and put a fiber on wire mesh lid over the top.
Same thing with the updraft hole..... blah blah blah...

Harvey Sadow