Paul on sun 21 jul 02
Hello,
Could anyone knowledgeable about glaze formulation please give some advice
on how to correct a crazing problem i am having? I have a slip glaze i use
that recently started crazing, and at this point i have added at least 30%
silica to the formula and it is still crazing. I have always found that
adding silica to my glazes more or less takes care of crazing issues, but in
this case it is not working. The recipe is approximately: whiting 10/ mixed
ash 30/ earthenware slip 30/ silica 30. Any suggestions? thanks!
Paul
Gavin Stairs on sun 21 jul 02
I have a question, rather than an answer. Did your recently change
your ash supply? Perhaps to an unwashed ash, or maybe a different
wood, or less grass or something?
If so, it may be that the alkali content of the ash has gone up too far
for you to reach with your silica adjustment. Not all ashes are
alike, and unwashed ash is particularly high in soda.
Gavin
At 10:48 AM 21/07/2002, Paul wrote:
Hello,
Could anyone knowledgeable about glaze formulation please give some
advice on how to correct a crazing problem i am having? ... The recipe is
approximately: whiting 10/ mixed ash 30/ earthenware slip 30/
silica 30. Any suggestions? thanks!
Paul
Gavin Stairs
Gavin Stairs Fine Editions
525 Canterbury Road
London, Ontario
Canada N6G 2N5
telephone: (519) 434-8555.
email: stairs@stairs.on.ca
Gavin Stairs Fine Editions is a small, computer press specializing in
book design and fine, hand-made books.
William Hendry on fri 26 jul 02
Paul, I'm curious, have you done anything different than before that might
make the glaze craze; eg, different clay body, different kiln, different
supplier of one of the raw materials, etc,?
William
----- Original Message -----
From: "Paul"
To:
Sent: Sunday, July 21, 2002 10:48 AM
Subject: CRAZING/SLIP GLAZE
> Hello,
> Could anyone knowledgeable about glaze formulation please give some advice
> on how to correct a crazing problem i am having? I have a slip glaze i use
> that recently started crazing, and at this point i have added at least 30%
> silica to the formula and it is still crazing. I have always found that
> adding silica to my glazes more or less takes care of crazing issues, but
in
> this case it is not working. The recipe is approximately: whiting 10/
mixed
> ash 30/ earthenware slip 30/ silica 30. Any suggestions? thanks!
> Paul
>
>
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