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help in firing cone 8-10 porcelain without warping

updated mon 30 jun 97


CCPottery on sun 8 jun 97

I have handbuilt a series of shallow porcelain bowls (2" h x 11" w) with
Highwater P10 porcelain. They are decorated with porcelain on the inside
which makes that one side heavy. I bisqued them to 05 with triangular
posts under the heavy side for support and they came out fine with no
warping or cracks. Now the problem is how to high fire them with a clear
Plan A is to clear glaze them and very slowly fire them to Cone 9 and soak
- I have a Skutt computerized kiln so this would be simple- but without
support I think they will warp. If I only glaze the inside I could let
them support each other - will this work??
Plan B is to only fire them to the lowest end of the range - Cone 8 and
not push my luck.
Plan C is to be a coward and Raku fire them with a crackle glaze.
Someone told me that if I fire them on silica they will resist warping -
is this true? Thank you for any help !!! Chris

NAME on sun 8 jun 97

Have you considerd bisqueing at cone 9 and then glazing at a lower temp?
This would allow you to stack or support your porcelain in various ways
without worring about mussing the glaze. Ive used sand to support china
in clay saggers or boxes without any warpage.