Russel Fouts on wed 1 jan 03
I'm pretty sure it isn't acting as a flux at that temp. Is it working as
an opacifier?
It's only 2 percent in the glaze I'm thinking of.
Thanks and Happy New Year Everyone.
--
Russel Fouts
Mes Potes & Mes Pots
Brussels, Belgium
Tel: +32 2 223 02 75
Mobile: +32 476 55 38 75
Http://www.mypots.com
Home of "The Potters Portal"
Over 1800 Pottery Links!
Updated frequently
"Is the Hokey Pokey really what it's all about?"
Russel Fouts on fri 3 jan 03
Thanks Tom,
That was my suspicion. Tony's site lists it as a filler for low temp
bodies but says nothing about low temp glazes. The CaO is only 4%. The
other opacifier is Zircopax at 11%. Would the opacifying effect be much
different with the CaO left out?
Russel
Tom Buck wrote:
>
> yes, Russ, at C07/05 range the CaO (from whiting at high temp, complete
> before 1000 oC) doesn't function as a flux oxide, but as a "filler" or
> opacifier. Eppler, a glaze expert in industry for 30 years, says CaO
> doesn't begin to act as flux until Cone 01/1.
> and Happy New Year to you. peace Tom
>
> Tom Buck ) -- primary address.
> "alias" or secondary address.
> tel: 905-389-2339 (westend Lake Ontario, province of Ontario, Canada).
> mailing address: 373 East 43rd Street, Hamilton ON L8T 3E1 Canada
--
Russel Fouts
Mes Potes & Mes Pots
Brussels, Belgium
Tel: +32 2 223 02 75
Mobile: +32 476 55 38 75
Http://www.mypots.com
Home of "The Potters Portal"
Over 1800 Pottery Links!
Updated frequently
"Is the Hokey Pokey really what it's all about?"
Linda Arbuckle on sat 4 jan 03
In Ceramic Science for the Potter by Lawrence, the Appendix A-2 shows a
eutectic for 73% boron and 27%calcium oxides that melts at 980 C or 1796
F cone 09-08 depending on whether you're using large or small cones). If
the Ca in whiting forms a eutectic it can function as a flux at lowfire
temps.
Linda Arbuckle, Professor
University of Florida
School of Art and Art History
P.O. Box 115801
Gainesville, FL 32611
http://www.arts.ufl.edu/artex02/html/ceramics/arbuckle.html
(352) 392-0201 x 219
Edouard Bastarache on sat 4 jan 03
Hello,
I have made c/04 glazes containing more than 40% washed hardwood ash,
mainly made up of calcium oxide. A boron frit plus a potassium spar were
also added, and china clay, ex:
Hardwood ash (washed) 42.5
Custer spar 13
Frit #3134 31
EPK 13.5
Totals 100
Later,
"Ils sont fous ces Quebecois"
Edouard Bastarache
Irreductible Quebecois
Indomitable Quebeker
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
http://sorel-tracy.qc.ca/~edouardb/
http://perso.wanadoo.fr/smart2000/index.htm
----- Original Message -----
From: Linda Arbuckle
To:
Sent: Saturday, January 04, 2003 1:54 PM
Subject: What's the function of Whiting in a ^05 Glaze?
> In Ceramic Science for the Potter by Lawrence, the Appendix A-2 shows a
> eutectic for 73% boron and 27%calcium oxides that melts at 980 C or 1796
> F cone 09-08 depending on whether you're using large or small cones). If
> the Ca in whiting forms a eutectic it can function as a flux at lowfire
> temps.
>
>
>
> Linda Arbuckle, Professor
>
> University of Florida
>
> School of Art and Art History
>
> P.O. Box 115801
>
> Gainesville, FL 32611
>
> http://www.arts.ufl.edu/artex02/html/ceramics/arbuckle.html
>
> (352) 392-0201 x 219
>
>
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Russel Fouts on sun 5 jan 03
Edouard
>> I have made c/04 glazes containing more than 40% washed hardwood ash,
mainly made up of calcium oxide. A boron frit plus a potassium spar were
also added, and china clay, ex:
Hardwood ash (washed) 42.5
Custer spar 13
Frit #3134 31
EPK 13.5
Totals 100
>>
Low temp ash glazes, those must be really interesting.
However, isn't 3134 a ^016 glaze all by itself? At ^04 wouldn't it be
the flux and not the calcium? The Calcium is probably a filler and being
the wood ash would adds some "interest".
Based on what Tom wrote and this, I'm beginning think that the whiting
is just a filler at that temperature.
Other than the 73% boron and 27%calcium eutectic melting at 980c
mentioned above by Linda.
Russel
----- Original Message -----
From: Linda Arbuckle
To:
Sent: Saturday, January 04, 2003 1:54 PM
Subject: What's the function of Whiting in a ^05 Glaze?
--
Russel Fouts
Mes Potes & Mes Pots
Brussels, Belgium
Tel: +32 2 223 02 75
Mobile: +32 476 55 38 75
Http://www.mypots.com
Home of "The Potters Portal"
Over 1800 Pottery Links!
Updated frequently
"Is the Hokey Pokey really what it's all about?"
Edouard Bastarache on sun 5 jan 03
Hello Russell,
These glazes look great, indeed; I have also never heard the word
"filler" in glaze technology.
Calcium contributes to the hardness and durability of glazes. It also
renders
low-fired glazes high in lead oxide or sodium oxide harder and more
insoluble,
which is not a bad thing after all.
The idea to use so much wood ash was to help someone get off welfare by
making and selleing low-fired wares. To do this we decided to use as much
waste materials as possible, such as hardwood ash from his house furnace
and, different waste materials from the local steel industries, as colouring
materials.
I remember telling him CaO was not a low-temp. flux, but that we
would "melt the calcium" by using strong low-temp fluxes such as sodium,
potassium, lithium, boron and even lead for non-utilitarian wares.
Later,
"Ils sont fous ces Quebecois"
Edouard Bastarache
Irreductible Quebecois
Indomitable Quebeker
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
http://sorel-tracy.qc.ca/~edouardb/
http://perso.wanadoo.fr/smart2000/index.htm
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