Carolyn Bronowski on tue 14 oct 03
Hi Clayarters-I've been successfully pulling terra sig pots out of ^11
bisque, but in this last load I had several pots where the terra sig had
peeled off in spots. Maybe they were too close to the elements, maybe I
oversprayed those areas, and the terra sig was too thick. Anyway, what do I
do now with those pots? I've never put a glaze over tera sig. Thanks
Carolyn
Snail Scott on wed 15 oct 03
At 10:15 AM 10/14/03 -0700, you wrote:
>Hi Clayarters-I've been successfully pulling terra sig pots out of ^11
>bisque...terra sig had peeled off... Maybe they were too close to the
elements, maybe I
>oversprayed those areas, and the terra sig was too thick...
Probably not caused by overheating. More likely it was too
thick, or not fully dry underneath, or heated too fast, or
a combination of any of those conditions. Moisture under
the terra sig can be trapped by the 'sealed' tight coating
of the terra sig, even while still unfired, and the steam
which outgasses during the early stages of firing may force
its way out and loosen the terra sig from the underlying
clay. (By the way, I'm assuming that you bisqued to ^011?)
You should be able to glaze over the terra sig without
difficulty, IF the remaining terra sig is well bonded to
the clay. If the remainder is a little loose, the glaze
will also end up being a little loose, and the glaze may
actually pull it off further. So, remove as much terra
sig as possible before glazing.
-Snail
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