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sv: hansen 5x20 variations/paul/plus raku glaze

updated mon 26 mar 01


will edwards on sun 25 mar 01


I finally got Alisa's frit into my data banks. (thanks Alisa!) I also mad=
some comparisons with her frit to others and also done some recipe conver=
just to see how it performs. (I checked over 100 frits for comparisons). =
also have a new frit that I will be testing for raku glazes. they are so =
chemicals and analysis to make my brain is fried.

Frit 3134 and Frit 169 are different. But I also noted that frit 169 did =
do a
good job in the testing for a comparitive to GB based on what she has ava=
in her area. (It also made several of the glazes I played with much more
stable. (Barium is in it/Hazard) So that should be taken into considerati=
prior to jumping in and looking for 169 as a replacement for GB. (Its all=
to you)

With all the people we have on here you'd think we could find a simple
solution to GB replacements but that is not the case. However I am going =
start working on my frit solutions once more as I have always done. Frits=
the way to go regardless of what was said in the past to me for being suc=
h a
frit advocate. I like commercial replacements made for big industry due t=
o QC,
larger batch formulations, more consistency from bag to bag, analyticals =
easy to get/prove, additions of other materials and minerals can replace =
or most of the GB formula's I have worked.
Those materials and minerals are standards for the most part and not subj=
to quick change. However I love to see all the news of up-coming replacem=
and certainly enjoy getting the molecular values of the chemistry for res=
purposes. Send me some more! (I will note that given a certain GB replace=
that is a one to one as declared, it is no where near a one to one but di=
show some real good results for raku replacement glaze formulations). Add=

Magnesium Sulphate and lower the bentonite to about 3% if needed at all.
Magnesium Sulphate should be supplied in raw form (Epsom salts) and mixed=
with the dry ingredients with a household blender using warm water at 0.7=
5 to
1% of the weight of materials that you normally would use. Let sit for a =
hours and re-mix. It should be of a brushable consistency for copper lust=
and several other raku glazes.

Edward's RAKU (COPPER 1) Revised 1629deg.F. (More or less) =

Formula Weight% Recipe

0.2870 8.64% Murrays Borate 65.00
CaO 0.7036 17.95% Neph. Sye. Blue Mountain 25.00
MgO 0.0094 0.17% EPK Kaolin 5.00
Al2O3 0.1819 8.43% Borax 4.00
B2O3 0.8432 26.68% Magnesium Sulfate 1.00 (Epsom salt)
SiO2 1.3949 38.11% Copper Carbonate 2.50
TiO2 0.0005 0.03% =

K2O 0.0373 1.60% =

Na2O 0.2498 7.04% =

Al:Si 7.6685 =

Expan. 11.6122 =

ST 241.363 =

Remove from kiln and immediately reduce as usual. Since I had the MB stu=
ff I
had to find something to use it for. (All artist need to test in their ow=
methods.) The above is no more than an example to try. The Epsom salts is=
there for the trace of Magnesium among other properties. =

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