Susan on fri 8 feb 02
would epsom salts in clay bodies corrode electric kiln elements?
susan
> From: vince pitelka
> Reply-To: Ceramic Arts Discussion List
> Date: Thu, 7 Feb 2002 20:38:41 -0600
> To: CLAYART@LSV.CERAMICS.ORG
> Subject: Re: epsom salts in porcelain, Help
>
>> Would this be a good example to demo flocculation as a way to improve
> plasticity?
>> I'll try it and see. This is a concept I'm trying to get across to some
> students.
>> And the .5% is negligible as a change in body fluxes for firing
> maturation.
>
> Roger -
> Well yes, because that is precisely the point, especially in any claybody
> tending towards alkalinity. And in communications and recipes I always
> write "1/2 of 1%" rather than ".5%" because in the latter the decimal is too
> often overlooked.
>
> For an effective demo of flocculation in claybodies, just mix ten pounds or
> so of porcelain body deflocculated with 1/4 of 1% each of soda ash and
> sodium silicate. Wedge it very well, and then have the students do some
> simple plasticity tests involving bending and stretching. The clay should
> be VERY short, and pretty much unworkable. Then mix up a small amount of
> saturated Epsom salt solution. Take a good chunk of the short porcelain,
> poke a few finger holes in it, and give it a few squirts of the Epsom salt
> solution, wedge thoroughly, and repeat the plasticity tests. Wonder of
> wonders.
> Best wishes -
> - Vince
>
> Vince Pitelka
> Appalachian Center for Crafts
> Tennessee Technological University
> 1560 Craft Center Drive, Smithville TN 37166
> Home - vpitelka@dtccom.net
> 615/597-5376
> Work - wpitelka@tntech.edu
> 615/597-6801 ext. 111, fax 615/597-6803
> http://www.craftcenter.tntech.edu/
>
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vince pitelka on fri 8 feb 02
> would epsom salts in clay bodies corrode electric kiln elements?
Susan -
We are talking about a minute amount of a non-volatile acidic compound, so
no, Epsom salts would not damage electric kiln elements at all. Remember
that silica is acidic, and clay/glaze is mostly silica. That's why you want
to keep glaze off of your kiln elements.
Best wishes -
- Vince
Vince Pitelka
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
Home - vpitelka@dtccom.net
615/597-5376
Work - wpitelka@tntech.edu
615/597-6801 ext. 111, fax 615/597-6803
http://www.craftcenter.tntech.edu/
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