On Mon, 29 Nov 2004 09:21:35 GMT, "JM" wrote:

Yeh, I constantly turn the pot so that the temp is even. I also keep the
gun away some distance, so the heat is not fierce.
My last tutor used to bring a large gas bottle and a blow torch to class,
and we used to use that. Those who were not used to using the blow torch
method would find that, if you were not careful, small chips would shoot off
the ware! It was quicker, but I found my little gun perfectly adequate, and
in my mind, a lot gentler on the ware.
JM

"Bob Masta" wrote in message
...

Just a thought, but try skipping the hot air gun on a few
pieces. I'd guess that drying the surface much faster
than the interior must be building up some stress.

Actually, the stress I was thinking about is between the
interior and exterior of the clay itself, so constant
turning won't help. The idea is that the skin dries out
quickly to a certain depth, but the interior is still wet.
Then as the interior does dry later, the shrinkage
causes stress build-up because the exterior is already
dry and can't shrink to match it. Or another way to
think about this is that the rapid exterior drying may be
causing rapid exterior shrinkage, which causes invisible
cracks because the interior is not shrinking to match.
The cranks only show up later.

At any rate, if you skip the hot air gun on a few
pieces and let them dry naturally (however long
that takes) and the problem goes away, then
you know where to look.

Best regards,


Bob Masta
dqatechATdaqartaDOTcom

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