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raku crackle glaze

updated fri 12 oct 01


Roger King on mon 17 mar 97

I'm looking for a low fire (06-07) white crackle glaze that preferably
has large (not fine) crazing marks in Raku. Any input is greatly
Kevin King

TONICLAYS@AOL.COM on sat 21 jul 01

A common crackle glaze was 20%neph sye and 80% Gerstley borate. I have only
tested the laguna borate sub and the Murray's borate sub. Both gave a good
crackle but the Murray's (with bentonite added, about 2%) was a little easier
to work with and stayed in suspension better and longer. We do enjoy
rakuing here and if you need more help check out some good books as resources
for info like Piepenburg's raku book (lots of recipes), or Steven Branfman's
book also. Also check the clayart archives for recipes and info on the
substitutions to help you decide. Happy raku-ing. Toni Smith , just back
from Ann Arbor where the art fair filled my head with ideas and inspiration.
Talked to some very friendly(considering the heat) potters who were also very
talented, hard workers.

Ababi on thu 11 oct 01

I have 100 most relayable white crackle raku glazes,it seems that the
problem is not on the relayable-ness of the glaze but on the smoothness
of the ware
---------- Original Message ----------

>Since you claim to be the 'raku guru' I thought I would inquire if you
>a dependable crackle glaze that you could share.



Ababi on thu 11 oct 01

Dear Carolsan - too!
It is not that simple after all. If the frit is without alumina-fine
but if the frit has alumina not good. If it is inside a ball no
problem, outside, might be.
The main point. if you burnish the ware or at least cover with smooth
slip, the glaze kind of (literately) floating on the ware, and only
eventually . relax, somehow, and has big areas, means big crackles.
David Jones in his book suggest to test raku glazes according to this
way, more or less, the book is not in front of me.
Frit, mainly borax, I have a good one without borax, I tried it too..
So frit + kaolin. Start from 85% frit 15 kaolin up to 95-100frit 5-0
Of coarse a glaze addict tries also 42.5 frit a + the 42.5% frit b+ the
Kaolin, but this is only instead of cigarets
Again the book is not in front of me. Of coarse, none kaolin might
cause flaking off- of the glaze.
The way my local adviser says that it is very simple,it is true, but it
is still difficult! Yet it is a glaze that you must test yourself.
I mailed a few times the Slip I use (basically from VC). If you want I
will send you off list.
Ababi Sharon
Kibbutz Shoval- Israel
officially Glaze addict

---------- Original Message ----------

>Dear Carolsan,.
>Reliable Raku crackle glaze. From Steve Mills.
>85 Any Frt
>15 China Clay
>1 Bentonite

>or I use it like this
>100 Any Frit (I use a Boron Frit, melts at ca. 700c.)
>4 Bentonite

>Opacify both with 12 to 15% Zircopax

>Best regards,
>Alisa in Denmark