Larry, my experience with explosions is usually due to moisture in the
clay. Do a moisture check before turning the kiln up by holding a mirror
or a metal object next to the top peep hole. If you get a fog on the
mirror, there's still moisture in the clay, and are more apt to explode.
Don't turn up to high until there is absolutely no moisture on the mirror.
>opened my kiln, and all three of my wheel thrown pieces with the white
>midfire clay had their bottoms blown out. All other projects were of
>the Mid Range Oxidation (red earthenware) and no problems. Fired at
>08... One larger piece disintegrated entirely.
>Wondering if because there is less grog/grit in white clay, if it is
>that much more pertinent to bisque fire at slowest speeds? I fired at
>Medium speed, to about 1700 degrees. The white clay was all new out of
>the bag, and wedged well....