Ababi on thu 25 sep 03
In my earlier letter I wrote I did not think every glaze should be food
safe.
Some glazes like ^6 crystal glazes rarely work without lithium
carbonate so is my imitation to reduction ash glazing
http://members4.clubphoto.com/ababi306910/1360168/
the point is to know what you do why you do and what is actually in this
white powder in your hands right know!
Simple glaze recipes and "playing around".
************************************
Tony Hansen's 20/5 is a better starting point to "play around" than the
glaze I have sent in my former letter.
Please read Tony Hansen's words.
And come back.
http://www.digitalfire.ab.ca/cermat/education/114.php
When Ron Roy told me to reduce the EPK and add feldspar to the
Huddleston glaze he knew for sure that I would give some time to see if
the new recipe is balanced. I might come to 18 EPK and 12 feldspar or 22
English kaolin and 8 feldspar.
This is fine.
When a guru or teacher tells you Remove A and add B, you are amazed: How
did he/she know? After all most of those powder look the same!
True, most of them look the same.
Sugar, salt, Magnesium sulfate and Trysodium Phosphate look the same but
for your health sake you better know their right use.
Using your software or Gary Wang's you can learn more about the analysis
of the given glazes.
I want to go on presuming that you are not using software.
Frit Ferro 3110
Frit Ferro 3124
Frit Ferro 3134
Very similar names. Are they changeable one for one?
The first answer is: If you want the same results with the same amounts
of the whole recipe 20%X5 materials the answer is no way!
Just for curiosity, if you can effort it, take the recipe;
TONY'S 20.5
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
Cone 6 1222 deg.C. -
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
Ferro 3134 20.00
Custer feldspar 20.00
EPK Kaolin 20.00
Flint 20.00
Wollastonite 20.00
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
Seger Weight%
KNO 0.219 4.87%
CaO 0.756 12.98%
MgO 0.025 0.31%
Al2O3 0.378 11.79%
B2O3 0.226 4.81%
SiO2 3.547 65.24%
K2O 0.073 2.10%
Na2O 0.146 2.77%
Al:Si 9.38
Expan. 6.96
ST 352.61
And once change the frit into 3110.
20.5
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
Cone 6 1222 deg.C. -
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
frit 3110 20.00
Custer feldspar 20.00
EPK Kaolin 20.00
Flint 20.00
Wollastonite 20.00
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
Seger Weight%
KNO 0.322 6.41%
CaO 0.651 10.13%
MgO 0.028 0.31%
Al2O3 0.445 12.57%
B2O3 0.028 0.54%
SiO2 4.201 70.04%
K2O 0.099 2.58%
Na2O 0.223 3.83%
Al:Si 9.45
Expan. 7.23
ST 357.10
Higher expansion, in my kiln and my claybodies would not mater.
20.5
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
Cone 6 1222 deg.C. -
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
frit 3124 20.00
Custer feldspar 20.00
EPK Kaolin 20.00
Flint 20.00
Wollastonite 20.00
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
Seger Weight%
KNO 0.202 4.18%
CaO 0.769 11.74%
MgO 0.028 0.31%
Al2O3 0.499 13.85%
B2O3 0.151 2.85%
SiO2 4.103 67.07%
K2O 0.087 2.24%
Na2O 0.115 1.94%
Al:Si 8.21
Expan. 6.59
ST 364.26
Lower expansion a silkier rather than gloss.
Now let's become wilder:
Change the feldspar potash to feldspar soda
Or both feldspar soda and frit 3110.
Or the Wollastonite into dolomite and in the next test to talc.
I would add a small amount of coloring oxide.
When I have high soda 1-3% copper oxide.
High Mgo 0.5 cobalt oxide.
What about
The Wollastonite changing into 15 zinc and 5 flint?
I would ad 1-2% Nickel oxide.
Those are easy games you can do without learning too deep, just enough
to know what these simple changes are doing to your glazes.
Because all that was left is the name, you can try to apply them one on
the other for interesting effects
The limits will wait.
Good night
Ababi Sharon
Glaze addict
Kibbutz Shoval Israel
ababisha@shoval.org.il
http://members4.clubphoto.com/ababi306910
http://www.matrix2000.co.nz/Matrix%20Demo/Ababi.htm
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