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saggars -reply and shinos

updated sat 30 nov 96


"Rafael Molina-Rodriguez (Rafael Molina-Rodriguez)" on tue 26 nov 96

Carole :

In my experience, a vent hole is not necessary with a saggar. I've fired
saggars at low temperatures (1600 F) and high temperatures (2400 F).

I've made my saggars by throwing and by slab construction. I use a
very coarse stoneware to help with thermal shock of repeated firings.
The thrown saggars are just a cylinder, with or without a bottom. The
slab saggars are constructed by draping around a cardboard tube. It's
the kind that is used to pour concrete piers. They come in different
diameters and lengths. I sometimes attach a slab base and other times I
don't. The lids are separate slabs that are the same diameter as the
mouth of the saggar. When the lid is placed on the saggar it's snug but
not "airtight' by any means, hence no vent holes.

Now, when I fire at low temperatures, I buy my saggars. I go the local
Home Depot and purchase terra cotta planters and saucers that are the
corresponding size as the opening of the planters. The planters only last
one or two firings but the saucers last numerous firings. I feel $ 7 or $ 8
is a small expense, along with the clay cost, that I can make back on the
retail sale of each piece.

When I use saggars in high fire I no longer use a lid. Just a cylinder
surrounding the object. Sometimes just the lower part of a piece is
protected by the saggar (see Troy's The glazes that
react well to this technique are celadons, copper reds/purple, and
especially shinos. IMHO the carbon trapping in shinos is encouraged by
placement in a saggar.

On the subject of shinos, I must say a fellow Clayarter Malcolm Davis is
one of the best. The two MD glazes in Troy's, one of
which was previously published in a Studio Potter article, are
outstanding. Where thin a vibrant orange and when applied thickly yield
yellow/gold/metallic with carbon trap stippling.

I hope I haven't strayed too far from subject. Good luck!


>>> 11/24/96 10:16am >>>
----------------------------Original message----------------------------
I know I should know the answer to this - but I don't. When you put a
in the kiln, should you have a vent hole in the top?

Carole Rishel
Bastrop, TX