Fay & Ralph Loewenthal on tue 12 may 98
Dear Clayarters, especially the Seth Efrican ones, I have a
request from a production potter. He wants to make flame
proof ware, and needs a source of suitable clay or a recipe.
If there are no SA potters with such knowledge then any
recipe will do, but I will have to have the chemical formula of
the ingredients in order to be able to substitute ingredients.
TIA Ralph in PE SA
Tony Hansen on thu 14 may 98
>Dear Clayarters, especially the Seth Efrican ones, I have a
>request from a production potter. He wants to make flame
>proof ware, and needs a source of suitable clay or a recipe.
>If there are no SA potters with such knowledge then any
>recipe will do, but I will have to have the chemical formula of
>the ingredients in order to be able to substitute ingredients.
You need low silica clays (ball clays are high silica)
and as much low expansion mineral as the body will take and
still be plastic enough. Use Pyrolphylite, kyanite, mullite
etc. Add bentonite if needed to reduce the clay portion
still further. Some flameware bodies have 90% or more low
expansion non-plastic mineral.
Don't worry about the chemistry of the ingredients, the
mineralogy, particle size, etc are the key.
--
T o n y H a n s e n thansen@digitalfire.com
Don't fight the glaze dragon alone
INSIGHT, Magic of Fire at http://digitalfire.com
Myrrhia Rae Resneck-Sannes on thu 14 may 98
Go to the library or to your local ceramix supply store and look for a
book on clay bodies. There should be several recipes available. You
must construct flameproof vessels with very even wall or they will crack
anyway. Good luck.
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