fyi... you could try mixing a smaall percentage of silica sand into the
plaster mold...it will hold up in the kiln better...but i am unsure about
the toxic nature of silica....
From: firstname.lastname@example.org [mailto:email@example.com]
Sent: Wednesday, February 19, 2003 8:54 AM
To: ArtsEdNet Talk
Subject: RE: Can plaster be fired in a Kiln...
I have used plaster in a kiln, but at relative low temperatures. The reason
I had it in the kiln was that we were doing glass sculptures -- we made clay
masks, being careful not to leave undercuts, poured plaster around them to
make molds, removed the clay after the plaster hardened, filled the plaster
mold with pieces of glass, and placed the mold in the kiln to melt the
glass. I had mixed results -- some of the molds broke apart when heated --
however I did get some good results from others. I suspect the difference is
in having the plaster as dry as possible, and being able to get the kiln
just hot enough to melt the glass without going hotter. Obviously, there is
likely to be air bubbles in the plaster too, which of course, along with the
moisture is a problem.
>A question for my friends...
>The other art teacher at school wants to fire plaster in the kiln. If this
is safe and how must it be done? Are there any special instructions that we
need to know before she tries it?
>Thanks for your replies,
>Idus in Southern Mississippi ( about one hour from New Orleans)