Ababi Sharon on wed 19 sep 01
GLAZES CONE 6 by Michael Bailey is an excellent and clear book.
focusing on ^6 perhaps ^7 glazes.
When you limit yourself to one cone you can write widely and clear.
Allow the smart reader understand what you write perhaps get conclusion
about other cones too. Steve Mills is as seen in the book a great
painter (plotter).
Dori who sufferers from a bad glaze, which on my claybodies is one of
the best ^6 glaze might learn to adjust his glaze even without the
using of a software ( Two are better).
To the tests I made:
Dolomite Crystalline glaze:
Two of my materials potash and soda feldspar do not have a clear
analysis, adopted from similar materials. However,here it worked good.
DOLOMITE CRYSTALINE MATTE1 1201deg.C. Cone 6
------------------------------------------------------------------------
----------------------------
Formula Weight% Recipe
------------------------------------------------------------------------
----------------------------
KNO 0.1987 5.73% SILICA 25.00
CaO 0.5721 12.58% ENGLISH KAOLIN CC31 6.00
MgO 0.0641 1.01% ZINC OXIDE
5.00
ZnO 0.1652 5.27% FELDSPAR SODA 45.00
Al2O3 0.3057 12.21% Calcium Carbonate 17.00
SiO2 2.6834 63.20% Bentonite 2.00
TiO2 0.0002 0.01% Dolomite 5.00
K2O 0.0716 2.64% Red Iron Oxide 8.00
Na2O 0.1271 3.09%
;
Al:Si 8.7773
Expan. 7.5214
ST 373.266
I raised the dolomite as Michael Bailey offers to 7.5,10,12.5 and 15.
I got kind of crystals similar to these ones in TEMMOKU GOLD, without
Lithium Carbonate.
Similarly the crystals appears better where the glaze is thicker.
Which test was the best? You must try and see what you like.
I tried the Idea of adding too much Silica. I wanted to get crackles
but did not. I used a recipe of mine, got nice white glazes.
Knowing my kiln and my preferences I changed base glaze 1 to fit to the
foodsafe limit table of Ron Roy and John Hesselberth and try above it
one of these glazes with rutile + cobalt +RIO. I got what I liked, the
colors separated. This way I can give it to my students. clear inside and adding other glazes on the outside.
You don't have the frit I use but you can learn from the analysis.
FOODSAFE ^6 1201deg.C. Cone 6 My ^6 is 1220C
------------------------------------------------------------------------
----------------------------
Formula Weight% Recipe
------------------------------------------------------------------------
----------------------------
KNO 0.2705 6.29% FELDSPAR SODA 3.35
CaO 0.4170 8.31% ENGLISH KAOLIN CC31 22.10
MgO 0.1776 2.54% Dolomite 12.86
ZnO 0.1349 3.90% ZINC OXIDE 3.58
Al2O3 0.3033 10.97%&n
bsp; Calcium Carbonate 4.01
SiO2 3.1850 67.96% SILICA 37.25
TiO2 0.0010 0.03% FRIT 2120 16.85
K2O 0.0297 0.99%
Na2O 0.2408 5.30%
Al:Si 10.5001
Expan. 7.3395
ST 362.863
Now Orange red Iron glazes.
this is what I did:
OR 1/1 orange red iron glazes
==============================
NR POTASH FELDSPAR. 16.53 16.53%
DOLOMITE............ 1.28 1.28%
LITHIUM CARBONATE... 3.14 3.14%
BONE ASH............ 11.27 11.27%
MAGNESIUM CARBONATE. 9.30 9.30%
CRYOLITE............ 7.48 7.48%
ENGLISH KAOLIN CC31. 11.62 11.62%
QUARTZ.............. 39.39 39.39%
========
100.00
CaO 0.35* 7.53%
Li2O 0.13* 1.48%
MgO 0.32* 4.91%
K2O 0.07* 2.45%
Na2O 0.13* 3.19%
SrO 0.00* 0.02%
TiO2 0.00 0.01%
Al2O3 0.25 9.67%
; P2O5 0.11 5.94%
SiO2 2.81 64.69%
Fe2O3 0.00 0.11%
Text1 9.15
Si:Al 11.36
SiB:Al 11.36
Expan 6.28
It is easier to me to do this function of formula to recipe in Insight like I wrote before better have two program, you navigate between the knowledge of two wise developers!
I got beautiful brown glazes
The idea here is to increase the amount of the RIO. again,you test to
see what you like
Last week I got from another supplier Custer Feldspar, costs about
twice but has analysis. I will repeat the test. The way the orange glaze looks in the book makes it a "must have" glaze.
I would like to thank Mike Bailey for clearing the darkness in my brain
about the meaning and calculation of coefficient of expansion that some
good clayarter tried to save me and did not succeed. Please send him my warm words!
Ababi Sharon
Kibbutz Shoval- Israel
officially Glaze addict
ababisharon@hotmail.com
http://members4.clubphoto.com/ababi306910/
http://www.milkywayceramics.com/cgallery/asharon.htm
http://www.israelceramics.org/
Get your FREE download of MSN Explorer at http://explorer.msn.com
Marianne Lombardo on wed 19 sep 01
I have a birthday coming up soon, and when my son asked me what I would =
like I told him I would really, really like to get this book. It sounds =
like a great book.
Marianne
GLAZES CONE 6 by Michael Bailey is an excellent and clear book.=20
focusing on ^6 perhaps ^7 glazes.
John Hesselberth on wed 19 sep 01
on 9/19/01 12:57 PM, Marianne Lombardo at mlombardo@NEXICOM.NET wrote:
> I have a birthday coming up soon, and when my son asked me what I would like I
> told him I would really, really like to get this book. It sounds like a great
> book.
>
> Marianne
>
> GLAZES CONE 6 by Michael Bailey is an excellent and clear book.
> focusing on ^6 perhaps ^7 glazes.
Michael is to be complimented for his presentation in this book. There is a
lot of good information. I particularly like it that a unity formula is
given for every glaze--that is a rarity--Val Cushing is the only other
person I am aware of that has done that in recent times. This means that
people in other parts of the world that may not have access to the same
ingredients have a pretty good chance of duplicating the glaze using locally
available ingredients.
When you give unity formulas, though, it also becomes obvious how many cone
6 glazes there are floating around potter-land that are very unstable. Of
Glazes GA1-GA30, which he has collected from several potters, I would
estimate only about 30-40% of them would be good functional glazes. Now
several of those are illustrated only on sculptural work, but at least a
couple very unstable glazes are shown on functional pieces. In fact a
couple of these look so bad I may just have found my next "lemon slice"
demonstration glazes. So please be careful if you use these glazes on
functional pottery.
I think it is interesting to note that of the 11-12 I think are stable, 7
were submitted by Clayarters Paul Lewing, Tony Hansen and Ron Roy.
Bottom line: There are a lot of unstable cone 6 glazes floating
around--also a bunch of cone 10 and earthenware ones--which should not be
used on functional pottery. Learn how to tell the difference if you are a
functional potter and always test your glazes (at least with the vinegar
test--preferably leach testing).
Regards,
John
Web site: http://www.frogpondpottery.com Email: john@frogpondpottery.com
"The life so short, the craft so long to learn." Chaucer's translation of
Hippocrates, 5th cent. B.C.
Ababi on thu 20 sep 01
You can see in my recipe that I went around. I shall try it again with the
Custer feldspar and if it will not work I will try to adjust it!
An extra challenge for the glaze addict!
While using it I will remember the potter from Custer!
----- Original Message -----
From: "Joan Ashworth"
To:
Sent: Thursday, September 20, 2001 05:07
Subject: Re: GLAZES CONE 6 by Michael Bailey
Ababi
I tested Michael Bailey's recipe for an iron orange glaze using South
African Materials and 13% local red iron oxide.
It was successful - a real orange, a lovely smooth glossy glaze - nice.
I am going to try it now with 11% iron to get a slightly lighter orange.
Joan Ashworth
in Durban
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Joan Ashworth on thu 20 sep 01
Ababi
I tested Michael Bailey's recipe for an iron orange glaze using South =
African Materials and 13% local red iron oxide.
It was successful - a real orange, a lovely smooth glossy glaze - nice.
I am going to try it now with 11% iron to get a slightly lighter orange.
Joan Ashworth
in Durban
Joan Ashworth on fri 21 sep 01
Tom Buck has suggested that I post the recipe for the Orange Glaze from
Michael Bailey's book.
Here it is:
Potash feldspar 46.7
Kaolin 4
Bentonite 2
Bone ash 15
Lithium carbonate 4
Talc 16.9
Silica 11.4
The orange shade is achieved in using red iron oxide between 11.5 and 13%
As you add iron, the shade goes darker and browner, until adding 24%, when
the colour is a rather 'dull' satin brown.
South African feldspar is fairly close to the old Kingman in analysis...
Joan
in Durban
Ababi on sat 22 sep 01
The analysis from the book is:
Oxide Analysis of OR 1
======================
.................... 7.45 7.45%
.................... 1.47 1.47%
.................... 4.89 4.89%
.................... 5.36 5.36%
.................... 1.18 1.18%
.................... 9.67 9.67%
.................... 5.92 5.92%
.................... 64.06 64.06%
========
100.00
CaO 0.35* 7.45%
Li2O 0.13* 1.47%
MgO 0.32* 4.89%
K2O 0.15* 5.36%
Na2O 0.05* 1.18%
Al2O3 0.25 9.67%
P2O5 0.11 5.92%
SiO2 2.81 64.06%
Si:Al 11.24
SiB:Al 11.24
Expan 6.41
I converted it in insight. Second time will try tomorrow or Sunday
OR 3
====
CUSTER FELDSPAR..... 46.64 46.64%
LITHIUM CARBONATE... 3.51 3.51%
TALC................ 14.22 14.22%
BONE ASH............ 12.57 12.57%
WHITING............. 0.52 0.52%
ENGLISH KAOLIN CC31. 3.65 3.65%
QUARTZ.............. 18.89 18.89%
========
100.00
CaO 0.35* 7.45%
Li2O 0.13* 1.47%
MgO 0.32* 4.89%
K2O 0.14* 5.04%
Na2O 0.06* 1.39%
TiO2 0.00 0.00%
Al2O3 0.25 9.66%
P2O5 0.11 5.92%
SiO2 2.81 64.07%
Fe2O3 0.00 0.09%
Text1 6.45
Si:Al 11.25
SiB:Al 11.25
Expan 6.40
In any case, even if I will "fail" I will learn new ways. My teacher, I
believe by mistake, considered bone ash like a "terrible" strong flux. It
might be depend of the rest of the family. As I have written before a spoon
of bone ash 24 gram if I remember + a spoon of rutile 13 gram if I remember,
will give a rich dry orange. Means, you can make this glaze with flux,
alumina and silica, yet it will be , include % bone ash. Food for your mind!
Ababi
----- Original Message -----
From: "Joan Ashworth"
To:
Sent: Friday, September 21, 2001 07:13
Subject: Re: GLAZES CONE 6 by Michael Bailey
> Tom Buck has suggested that I post the recipe for the Orange Glaze from
> Michael Bailey's book.
>
> Here it is:
>
> Potash feldspar 46.7
> Kaolin 4
> Bentonite 2
> Bone ash 15
> Lithium carbonate 4
> Talc 16.9
> Silica 11.4
>
> The orange shade is achieved in using red iron oxide between 11.5 and 13%
> As you add iron, the shade goes darker and browner, until adding 24%, when
> the colour is a rather 'dull' satin brown.
>
> South African feldspar is fairly close to the old Kingman in analysis...
>
> Joan
> in Durban
>
>
____________________________________________________________________________
__
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
>
mariko cruse on sat 22 sep 01
Hello Ababi,
I appreciate your posting recipies and analysis from the Michael Bailey's
Book.
I have a couple of questions to ask: Have you ever asked three or more
people to glaze and fire a given recipe using the same clay body, but each
having his/hers own firing protocol to reach Cone 6? And then, have you
ever compare the results?
I have, and each test tiles look differently. My point is, it is very
important to know the molecular analysis, but if we dont look at the firing
schedule, I am not sure if we will be talking about the same glaze. I am
not talking about our individual taste for the outcome, nor the differences
among kilns. I am merely wishing to know under what firing protocol was
the particular glaze fired, so that those who wish to reproduce it, will
have some idea about it. I seldom get to see a detailed firing schedule for
a given recipe. Am I asking too much? Mariko
----- Original Message -----
From: "Ababi"
To:
Sent: Friday, September 21, 2001 6:38 PM
Subject: Re: GLAZES CONE 6 by Michael Bailey
> The analysis from the book is:
> Oxide Analysis of OR 1
> ======================
> .................... 7.45 7.45%
> .................... 1.47 1.47%
> .................... 4.89 4.89%
> .................... 5.36 5.36%
> .................... 1.18 1.18%
> .................... 9.67 9.67%
> .................... 5.92 5.92%
> .................... 64.06 64.06%
> ========
> 100.00
>
> CaO 0.35* 7.45%
> Li2O 0.13* 1.47%
> MgO 0.32* 4.89%
> K2O 0.15* 5.36%
> Na2O 0.05* 1.18%
> Al2O3 0.25 9.67%
> P2O5 0.11 5.92%
> SiO2 2.81 64.06%
> Si:Al 11.24
> SiB:Al 11.24
> Expan 6.41
>
> I converted it in insight. Second time will try tomorrow or Sunday
>
> OR 3
> ====
> CUSTER FELDSPAR..... 46.64 46.64%
> LITHIUM CARBONATE... 3.51 3.51%
> TALC................ 14.22 14.22%
> BONE ASH............ 12.57 12.57%
> WHITING............. 0.52 0.52%
> ENGLISH KAOLIN CC31. 3.65 3.65%
> QUARTZ.............. 18.89 18.89%
> ========
> 100.00
>
> CaO 0.35* 7.45%
> Li2O 0.13* 1.47%
> MgO 0.32* 4.89%
> K2O 0.14* 5.04%
> Na2O 0.06* 1.39%
> TiO2 0.00 0.00%
> Al2O3 0.25 9.66%
> P2O5 0.11 5.92%
> SiO2 2.81 64.07%
> Fe2O3 0.00 0.09%
>
> Text1 6.45
> Si:Al 11.25
> SiB:Al 11.25
> Expan 6.40
>
> In any case, even if I will "fail" I will learn new ways. My teacher, I
> believe by mistake, considered bone ash like a "terrible" strong flux. It
> might be depend of the rest of the family. As I have written before a
spoon
> of bone ash 24 gram if I remember + a spoon of rutile 13 gram if I
remember,
> will give a rich dry orange. Means, you can make this glaze with flux,
> alumina and silica, yet it will be , include % bone ash. Food for your
mind!
> Ababi
> ----- Original Message -----
> From: "Joan Ashworth"
> To:
> Sent: Friday, September 21, 2001 07:13
> Subject: Re: GLAZES CONE 6 by Michael Bailey
>
>
> > Tom Buck has suggested that I post the recipe for the Orange Glaze from
> > Michael Bailey's book.
> >
> > Here it is:
> >
> > Potash feldspar 46.7
> > Kaolin 4
> > Bentonite 2
> > Bone ash 15
> > Lithium carbonate 4
> > Talc 16.9
> > Silica 11.4
> >
> > The orange shade is achieved in using red iron oxide between 11.5 and
13%
> > As you add iron, the shade goes darker and browner, until adding 24%,
when
> > the colour is a rather 'dull' satin brown.
> >
> > South African feldspar is fairly close to the old Kingman in analysis...
> >
> > Joan
> > in Durban
> >
> >
>
____________________________________________________________________________
> __
> > Send postings to clayart@lsv.ceramics.org
> >
> > You may look at the archives for the list or change your subscription
> > settings from http://www.ceramics.org/clayart/
> >
> > Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
> >
>
>
____________________________________________________________________________
__
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
iandol on sun 23 sep 01
Dear Mariko Cruse,
A valuable lesson in your statement. But I would like to emphasise the =
significance of cooling rates.
Since the primary objective of most glaze firings is to ensure all the =
ingredients either melt or dissolve in a melt so that a uniform blend of =
all the elements takes place there is possibly very little variation in =
glazes made by three people at that point in time when the cones set to =
indicate maturity has been achieved. But once heating is discontinued =
and cooling starts the example with the fastest cooling rate may be the =
most glass like, transparent and smooth and the one with the slowest =
cooling rate may turn our to be totally matt and opaque. The =
intermediate example might be patchy and varied in colour.
So it may be essential for the promoters of glaze recipes to indicate =
the rates of cooling which apply to their test firing schedules.
Best regards,
Ivor Lewis. Redhill, South Australia
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