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porcelain body --reply to brian

updated sat 23 jul 05

 

Dave Finkelnburg on fri 22 jul 05


Brian,
I have not tested this myself, but I have been told that alumina hydrate is what you want to use. The argument I have heard is that calcined alumina is harder to wet. You would have to allow for the greater LOI from the hydrate. I have observed, when making pure alumina suspensions, that without a dispersant or acid in the water the alumina tends to form clumps. Dry mixing the ingredients (at least the alumina and some clay), so the alumina is coated with clay, is the best way to prevent this problem when making a clay body. This is important to do with feldspar, too.
Good potting!
Dave Finkelnburg

Brian Molanphy wrote:
3. some recipes list calcined alumina and some alumina hydrate... what
difference does calcining make, and should it be calcined to bisc
temperature?





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