Pat Chesney on sat 4 oct 97
I am still looking for a clear gloss glaze to use in salt firing at cone
10. Our clear crazes in salt firings when exposed to the vapors. Any
favorites? We are firing with propane. We need a good liner for our bowls
and closed forms.
Pat Chesney
Pat-Chesney@easy.com
Waco, Texas
Vince Pitelka on sun 5 oct 97
>I am still looking for a clear gloss glaze to use in salt firing at cone
>10. Our clear crazes in salt firings when exposed to the vapors. Any
>favorites? We are firing with propane. We need a good liner for our bowls
>and closed forms.
>Pat Chesney
>Pat-Chesney@easy.com
>Waco, Texas
Pat -
Hope all's well at Brazos de Dios. For salt firings I have adjusted glazes
which tend to craze by reducing sodium fluxes, or if none are present,
reducing flux content altogether. The high-gloss clears are heavily fluxed,
and with the additional sodium vapor they are easily over-fluxed. You may
well get a good suggestion for a salt clear from the list, but if not, a
little experimentation should solve your problems. As you may know, because
of variable approaches to salt firing, glaze calculation programs do not
offer much help in glazes used in salt (except for liners which receive
minimal salt), so such a modification must be done by the seat of your
pants. Good luck.
- Vince
Vince Pitelka - vpitelka@DeKalb.net
Home 615/597-5376, work 615/597-6801, fax 615/597-6803
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
Richard Burkett on tue 7 oct 97
>I am still looking for a clear gloss glaze to use in salt firing at cone
>10. Our clear crazes in salt firings when exposed to the vapors. Any
>favorites? We are firing with propane. We need a good liner for our bowls
>and closed forms.
>Pat Chesney
>Pat-Chesney@easy.com
Hi Pat,
Vince's suggestions may well suffice in some instances, but there may be
other factors at work here. A lot of salt glazers cool the kiln very
quickly, and it is possible that this is having a detrimental effect on
crazing, too. Accurate firing to a specific cone may be necessary for
really good glaze fit, and this is usually difficult at best with salt, as
the cones may be affected by the salt vapor. Overfiring will often result
in glaze crazing.
With bowls you may always have the problem, as the glaze will usually
craze where the soda hits it from the high expansion effects of all that
sodium oxide, but if you try to adjust it for the rims then the glaze may
fit too tightly at the bottom of the bowl where there is usually less
effect from the salt glaze. Inside closed forms should be easier to fix,
as little sodium usually gets inside these pieces.
Richard
Richard Burkett - School of Art, SDSU, San Diego, CA 92182-4805
E-mail: richard.burkett@sdsu.edu <-> Voice mail: (619) 594-6201
Home Page: http://rohan.sdsu.edu/dept/rburkett/www/burkett.html
CeramicsWeb: http://apple.sdsu.edu/ceramicsweb/
HyperGlaze@aol.com & http://members.aol.com/hyperglaze/
Shelley S on wed 8 oct 97
Richard,
On your comment:
"Accurate firing to a specific cone may be necessary for
really good glaze fit, and this is usually difficult at best with salt, as
the cones may be affected by the salt vapor"
At what point are the cones affected? Are they affected throughout the
firing from residual salt, or is this more of a problem once you start
salting? Do you think it is best to get up to temp and then salt to get a
more accurate reading?
thanks,
Shelley
Ric Swenson on wed 8 oct 97
ClayArters,
You might try this clear glaze inside salt pieces.....
Frederick Carlton Ball's S.F.T. Clear Base ( Standard Felspathic
Transparent )
CONE 10
Potash Feldspar 45
Flint 22
Kaolin (E.P.K.) 13
Whiting 17
Zinc Oxide 3
_______________________
Total 100
(fires in reduction or neutral)
HTH....
Regards,
.......Ric
***********************************************************
FROM : Ric Swenson, Bennington College, Route 67 - A,
Bennington, Vermont 05201-6001 U.S.A.
( 802 ) 440 - 4621 or fax ( 802 ) 440 - 4582
email: rswenson@bennington.edu
"Opinions expressed are mine..... usual disclaimers apply."
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