[Clayart] Helen's firing

[Douglas Fur]

Helen
As Hank said getting to ^11 is a good sign that the kiln will work.
A bad first firing is common with vapor glazing kilns.
A long first firing is also a common occurrence. (What was the total time?)

What struck my is your description of a murky atmosphere and wondering
about damper management. This, and the fuel consumption, sounds like excess
fuel was a problem. A lower fuel setting and a neutral flame color could
fire the kiln in less time.

Adding a thin layer of hard brick: The thinner the layer the more likely it
will topple as the hot face expands, bending the tile. Dense fire bricks on
edge, 21/2" for US standard, plus 41/2" insulating brick on the outside
would be a good wall for a small kiln. Could you add a wall of bricks on
edge to the inside of the kiln? As your experiment showed, adding a coating
is tricky. This makes me wonder which would be worse, to leave the bricks
exposed to see what happens or to glaze the inside surface.

A caveat, my salt firing experience was in the late Holocene before soda
firing became common. In that era the best firing salt kilns were of hard
brick which developed a glazed surface. One kiln I helped build, which was
of high alumina brick, never developed a good glazed surface, took more
salt to get a good fire and was eventually torn down. I was on the crew
that tore down Hank's old salt kiln and the glaze on the bricks was
beautiful.

Happy firing
You're close to your goal.
Duff
Seola Creek
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