iandol on sun 25 jun 00
Craig,
Thanks for contacting Ian Currie. I knew there had to be a logic behind =
the pattern. Reading now makes sense. I'm sure the rest of the readers =
will appreciate Ian's long and humorous posting. Must break out the =
syringes and have a go.
All the best
Ivor
iandol on tue 27 jun 00
Lawrence, thanks for that information.
I appreciate that by entering things into Matrix, or any other up to =
date glaze program to which I can gain access, I can simulate the system =
devised by Ian.
However, this does not solve my problem. Your Matrix program will not =
explain why the spatial increments between the dots in the parallelogram =
area are not uniform, why they tend to spread away from each other like =
an expanding universe as they move away from the origin.
The original research paper of Stull and Howat would make interesting =
reading and perhaps show why this happens.
I would like to know how you explain the spatial discrepancy in the =
plot?
Best regards and thanks for your interest.=20
Ivor Lewis.
Lawrence Ewing on tue 27 jun 00
Ivor,
The latest version of Matrix Glaze Calcuation Software (Matrix V3) has a
facility for automatically generating all of the volumetric blending data
needed to make a Currie Standard Recipe Grid based on any glaze you have
previously entered and saved in Matrix.
In addition the the blending data Matrix will calculate the recipe unity
formula for each glaze in the grid and displays the grid recipes and
formulae on graphs.
his feature has enabled students at our school to explore variations on a
favourite glaze focusing on changes in the Al2O3 and SiO2 content of the
glaze.
You can check this feature out at the Matrix website
http://www.Matrix2000.co.nz
Click on the >>> recent developments in Matrix V3 link to see the window
used to generate the blend.
The Matrix website also has some examples of Currie Standard Recipe Grids
created by students at Otago Polytechnic School of Art in New Zealand.
Regards,
Lawrence Ewing
Senior Lecturer
Ceramics Department
School of Art
Otago Polytechnic
Dunedin
New Zealand
email: lewing@clear.net.nz
MATRIX GLAZE CALCULATION SOFTWARE:
http://www.Matrix2000.co.nz
GLAZETEACH:
http://www.Matrix2000.co.nz/GlazeTeach
MATRIX TUTORIALS:
http://www.Matrix2000.co.nz/MatrixTutorials
MATRIX ADDITIONAL MATERIALS RESOURCE:
http://www.Matrix2000.co.nz/MatrialsWeb/default.htm
Lawrence Ewing on fri 30 jun 00
Ivor,
There is a relatively simple answer to your question relating to the uneven
distribution of glazes generated using volumetric blending methods.
****************************************************************************
**
In the following first example a simple line blend is generated using
volumetric blending techniques with the original glaze labelled C and the
'target' glaze labelled D
We start with the C glaze in which any clay and silica materials are removed
and the recipe is converted to one totalling 100
Feldspar 50.98
Whiting 49.02
Next we add 100% silica for the D glaze then CONVERT THE GLAZE AGAIN TO
TOTAL 100
Feldspar 25.49
Whiting 24.51
Silica 50.00
When these glazes are volumetrically blended to make 7 samples we get the
following recipes:
Feldspar Whiting Silica
1.C 50.98 49.02
2. 46.73 44.94 8.33
3. 42.48 40.85 16.67
4. 38.24 36.76 25.00
5. 33.99 32.68 33.33
6. 29.74 28.60 41.67
7.D 25.49 24.51 50.00
The silica additions are constant increments of 8.33.
The unity formula for each of the above glazes show a constant flux group of
KNO 0.1544, CaO 0.8456 and a constant Al2O3 level of 0.1771.
The SiO2 mols vary unevenly as follows:
SiO2
1.C 0.9420
2. 1.2016
3. 1.5132
4. 1.8939
5. 2.3699
6. 2.9818
7.D 3.7977
****************************************************************************
**
In second example a similar line blend is generated using volumetric
blending techniques with the original glaze labelled C and the 'target'
glaze labelled D except that this time WE DO NOT CONVERT THE D GLAZE TO
TOTAL 100 after adding the silica.
We start with the C glaze in which any clay and silica materials are removed
and the recipe is converted to one totalling 100
Feldspar 50.98
Whiting 49.02
Next we add 100% silica for the D recipe
Feldspar 50.98
Whiting 49.02
Silica 100.00
When these glazes are volumetrically blended to make 7 samples we get the
following recipes:
Feldspar Whiting Silica
1.C 50.98 49.02
2. 50.98 49.02 16.67
3. 50.98 49.02 33.33
4. 50.98 49.02 50.00
5. 50.98 49.02 66.67
6. 50.98 49.02 83.33
7.D 50.98 49.02 100.00
The silica additions are constant increments of 16.67.
The unity formula for each of the above glazes show a constant flux group of
KNO 0.1544, CaO 0.8456 and a constant Al2O3 level of 0.1771.
The SiO2 mols vary unevenly as follows:
SiO2
1.C 0.9420
2. 1.4180
3. 1.8939
4. 2.3699
5. 2.8458
6. 3.3218
7.D 3.7977
The silica material additions in this example result in a constant increment
of 0.476 mols of SiO2 in the unity formulae for the glazes in the blend.
CONCLUSION
The simple action of converting the D corner glaze in the blend to total 100
before blending results in an uneven distributiion of molecular parts for
the SiO2 in the unity formulae.
I hope this throws some light on the phenomenon Ivor.
Regards,
Lawrence Ewing
Senior Lecturer
Ceramics Department
School of Art
Otago Polytechnic
Dunedin
New Zealand
email: lewing@clear.net.nz
MATRIX GLAZE CALCULATION SOFTWARE:
http://www.Matrix2000.co.nz
GLAZETEACH:
http://www.Matrix2000.co.nz/GlazeTeach
MATRIX TUTORIALS:
http://www.Matrix2000.co.nz/MatrixTutorials
MATRIX ADDITIONAL MATERIALS RESOURCE:
http://www.Matrix2000.co.nz/MatrialsWeb/default.htm
-----Original Message-----
From: Ceramic Arts Discussion List [mailto:CLAYART@LSV.CERAMICS.ORG]On
Behalf Of iandol
Sent: Tuesday, June 27, 2000 6:40 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: Ian Currie Glaze Test Method
Lawrence, thanks for that information.
I appreciate that by entering things into Matrix, or any other up to date
glaze program to which I can gain access, I can simulate the system devised
by Ian.
However, this does not solve my problem. Your Matrix program will not
explain why the spatial increments between the dots in the parallelogram
area are not uniform, why they tend to spread away from each other like an
expanding universe as they move away from the origin.
The original research paper of Stull and Howat would make interesting
reading and perhaps show why this happens.
I would like to know how you explain the spatial discrepancy in the plot?
Best regards and thanks for your interest.
Ivor Lewis.
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