Dave Finkelnburg on fri 25 aug 00
James,
I presume you intend to use this glaze at or near cone 10. If you do
the glaze arithmetic, or use a glaze calculation program like Tony Hansen's
Insight, you see this is a balanced glaze with key ingredients within, or
close to limits for C10. That's what makes it a good basic glaze recipe.
Basically, what those limits tell you is the glaze will melt, will form
some nice glass, will not excessively leach metal oxides added for color,
and will not run off the pot like water provided you don't add so much
colorant oxides that you overflux it. :-)
Per my version of Insight the Seger formula for this glaze, with the
iron and rutile added, is:
CaO 0.76
K2O 0.17
Na2O 0.07
TiO2 0.14
Al2O3 0.40
SiO2 3.90
Fe2O3 0.12
Si:Al 9.85
Expan 7.59
I hope this is helpful. By the way, I thought your question on water in
glaze was an excellent one, and well stated!
Dave Finkelnburg
J. Bowen wrote: There are many references in the literature of glazes
referring to a basic 4,3,2,1, glaze for stoneware. What makes it a basic
glaze recipe? How is such a recipe useful?
Example
Angel Eyes
Custer Feldspar 40%
Silica 30%
Whiting 20%
EPK 10%
ADD RIO 5%
Rutile 3%
Comment: Rutile blue; breaks to gold where thin. Iron painted over turns
gold.
Craig Martell on fri 25 aug 00
James asked:
>There are many references in the literature of glazes referring to a basic
>4,3,2,1, glaze for stoneware. What makes it a basic glaze recipe? How is
>such a recipe useful?
> Example
>Angel Eyes
>Custer Feldspar 40%
>Silica 30%
>Whiting 20%
>EPK 10%
Hi:
As far as what makes this a basic glaze recipe, it simply has what is
required to make a glaze. Fluxes, KNO from spar and CaO from whiting,
amphoteric or stabilizing oxide or stiffener in alumina from EPK, and glass
former from silica, EPK, and feldspar. I looked at the seger formula in
Insight and Matrix and it's a well balanced glass and with the colorants
you give, it would be a good functional glaze suitable for food use or
whatever application one would choose.
Is this what you meant?
Since this is a good, well balanced (OK, the Ca is a bit high but not too
bad!), durable glaze the best use would be determined by the maker and
their aesthetic sensibilities.
regards, Craig Martell in Oregon
James L Bowen on fri 25 aug 00
There are many references in the literature of glazes referring to a =
basic 4,3,2,1, glaze for stoneware. What makes it a basic glaze recipe? =
How is such a recipe useful?
Example
Angel Eyes
Custer Feldspar 40%
Silica 30%
Whiting 20%
EPK 10%
ADD RIO 5%
Rutile 3%
Comment: Rutile blue; breaks to gold where thin. Iron painted over turns =
gold.
Alisa and Claus Clausen on sat 26 aug 00
I read earlier on Clayart that the 40/30/20/10 glaze receipes were =
developed and/or made famous by Richard Behren.
He has book called Cermaic Glazemaking published by CM handboodks. The =
glaze mentioned int he post is
#410 Satin Matte Base Glaze
40 Volcanic ash
30 Whiting
20 flint
10 Kaolin
I am sure there are others that can elaborate on Mr. Behren. I find =
these glazes interesting as the materials are what
are usually ready on the shelf. I do not have the book, but would like =
to see it when I am in a good bookshop next.
Best regards,
Alisa Clausen
Carolyn Nygren Curran on sat 26 aug 00
If the 4-3-2-1 glaze is the same as 1-2-3-4 glaze, isn't that an old
Bernard Leach standby? The Behrens one looks like a variation on the theme
with volcanic ash.
cnc
Paul Taylor on sat 26 aug 00
Dear James
In Europe we called this a Leach cone eight glaze about 1260 c it is as
old as the hills. It is the glaze that you would know best as a one hundred
percent reliable with a huge firing range which is what makes it so useful.
Regardless of what feldspar or what china clay.
Weather it is so reliable is another question . But -- Who am I to argue
with tradition?
-- Regards Paul Taylor.
Westport Pottery, Liscarney, County Mayo. Ireland.
http://www.anu.ie/westportpottery/
> From: James L Bowen
> Reply-To: Ceramic Arts Discussion List
> Date: Fri, 25 Aug 2000 13:26:43 -0600
> To: CLAYART@LSV.CERAMICS.ORG
> Subject: 4,3,2,1 Glaze
>
> There are many references in the literature of glazes referring to a basic
> 4,3,2,1, glaze for stoneware. What makes it a basic glaze recipe? How is
> such a recipe useful?
> Example
> Angel Eyes
> Custer Feldspar 40%
> Silica 30%
> Whiting 20%
> EPK 10%
>
> ADD RIO 5%
> Rutile 3%
> Comment: Rutile blue; breaks to gold where thin. Iron painted over turns gold.
>
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
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>
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> melpots@pclink.com.
Larry Phillips on sat 26 aug 00
Dave Finkelnburg wrote:
>
> James,
> I presume you intend to use this glaze at or near cone 10.
> Basically, what those limits tell you is the glaze will melt, will form
> some nice glass, will not excessively leach metal oxides added for color,
> and will not run off the pot like water provided you don't add so much
> colorant oxides that you overflux it. :-)
Is there something similarly reliable with the ability to take colorants
for cone 5 or 6?
--
Hukt on fonix werkt fer me!
http://cr347197-a.surrey1.bc.wave.home.com/larry/
ferenc jakab on sun 27 aug 00
----- Original Message -----
From: "Alisa and Claus Clausen"
To:
Sent: Sunday, 27 August 2000 2:50 am
Subject: Re: 4,3,2,1 Glaze
I read earlier on Clayart that the 40/30/20/10 glaze receipes were developed
and/or made famous by Richard Behren.
I believe the 4321 glaze was originally set down by Bernard Leach as a basic
cone 10 recipe to use as a standard for either testing other glaze
variations against or as a stable base to be used as a point of departure
for formulating cone 8 - 10 glazes.
Feri.
Em1312@AOL.COM on mon 28 aug 00
This glaze used by Jack Troy found in this month's issue of Clay Times.....do
we assume it is red iron oxide when we see iron oxide as an ingredient ? I do
know there is also a yellow iron oxide and black iron
oxide.......????????Thank you!!!!
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