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cone 10 to c.6 again

updated sun 13 apr 08


Lili Krakowski on sat 12 apr 08

Some nice person--lost track of the original post--wanted help moving a c.10
glaze down
to c. 6.

Sheffield Slip 36.0
Custer Feldspar 22.0
Gerstley Borate 3.0
Wollastonite 14.0
Flint 14.0
Kaolin (EPK) 3.0
Whiting 8.00
Add: Cobalt Carbonate 2.0 and Milled Rutile 1.0

I had to look up Sheffield slip on the Internet, and found only the info
that it is more refractory than Albany Slip. Still I used Albany as given by
Digital Fire for this calculation.

Recipe Name: test

Cone: Color:
Firing: Surface:

Amount Ingredient
36 Albany Slip [Digital Fire]
22 Feldspar--Custer
3 Gerstley Borate--1999
3 Kaolin--EPK
14 Wollastonite
8 Whiting
14 Flint

100 Total

Unity Oxide
.054 Na2O
.111 K2O
.093 MgO
.742 CaO
1.000 Total

.323 Al2O3
.034 B2O3
.039 Fe2O3

3.013 SiO2
.006 TiO2
0 P2O5

Calculations by GlazeMaster(tm)

So, one thing to try is to replace some of the Sheffield with RedArt.

Then, because the clothing dryer takes forever, I figured out the following.

46.3 Albany slip [Digital Fire]
0 Nepheline Syenite
12 Frit--Ferro 3134
10 Frit--Ferro 3110
13 Whiting
3.7 Bentonite

85 Total

Unity Oxide
.156 Na2O
.055 K2O
.102 MgO
.687 CaO
1.000 Total

.231 Al2O3
.13 B2O3
.048 Fe2O3

2.057 SiO2
.007 TiO2

8.9 Ratio
78.3 Exp

Calculations by GlazeMaster(tm)

What I did was to take out the Custer and the GB and used two
frits. I cannot figure out why so often, so many, hesitate to use more than
one frit in a recipe. Anyway. I raised the B2O3 which should help with the
melt,and lowered the alumina and silica. The iron is a bit higher now, not
sure that that will matter.

Be advised that I do not fire in reduction so the iron MAY matter. Try the
glaze, and please tell us if it works. It would be so nice if people
reported back, because then others can learn.

Lili Krakowski

Be of good courage