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finishing help please!...totally easy terra weighing

updated tue 31 dec 96


Martin Butt on sun 29 dec 96

Deb & Curt;
I agree with the posts suggesting that using terra sig might give you the
finish you are looking for, but I also recall that you mentioned not having
access to weighing and mixing facilities. Try this! Purchase a gallon of
casting slip (should be available where you get your glazes), mix in a gallon
of water and let it sit in a clear container overnight. After a day or so it
should separate into two or three distinct layers. It may have a layer of
clear water on top; if so, siphon off and discard. Next will be a layer of
fine clay particles, the terra sig we are after. Siphon this off and save;
try not to suck up any of the bottom layer. Throw the bottom layer out.
Apply the terra sig to bone dry ware with a soft brush, laying on repeated
strokes around the whole piece untill the sig no longer dries immediately.
As soon as its not tacky, 10 sec. or so, polish with a crinkly plastic bag
from the grocery store. Right away it should take on a beautiful sheen with
very little polishing. Previous posts have suggested firing between cone 018
and cone 06, and they all seem to work. The lower temps leave the work a
little soft for my taste, so I now include the terra sig work in our regular
bisque firing at 06 with very little loss of polish.
I have tried this with a white earthenware slip, a red earthenware slip, and
a white stoneware slip, and they have all worked well; (I like the red better
than sig I mixed from scratch). An added bonus for those of you still unsure
about determining the various layers: The stoneware settled into a layer of
good stuff, and a layer of hard as a rock silica, feldspar, and coarse
clay...the white earthenware into good stuff and hard as a rock talc and
coarse clay. HARD to go wrong. Hope this helps.

Finally Finished Lurking,

Martin Butt
Coyote Craft School
5125 Edith NE
Albuquerque, NM 87107
(505) 344-2250 (505)