John Britt on thu 15 mar 01
Melinda,
That appears to be an Egyptian Paste recipe. The high soda content is to
allow the piece to self glaze upon drying.
As they are very unstable low fired glazes they will often "foam" after
firing.
But they do give some beautiful colors for sculpturalware.
See ya,
John
>
>----- Original Message -----
>From: "Ron Collins"
>To:
>Sent: Thursday, March 15, 2001 9:35 PM
>Subject: unusual glaze happening
>
>
>I recently mixed up a batch of glaze that we all love....EG-84 from CM
>article with a lot of recipes given by Woody Hughes. After firing, the
>pieces continue to form white powdery spots on the surface and have to be
>washed every few days.....I tried it in the first place because it only has
>8.5% imported lithium...other things are available here
>The recipe is
>Baking soda 30.5
>Lithium carbonate 8.5
>Kaolin 22.5
>Flint 38.5
>Add tin oxide 5%
>copper oxide 2.5
>bentonite 1%
>
>What would make the white powder after firing...same powdery results
whether
>06,04, over or underfired...I have only been working with and making low
>fire glazes for a year...never had this happen with stoneware...can someone
>tell me what's going on with it? Thanks so much, Melinda in Guatemala
>
Ron Collins on thu 15 mar 01
I recently mixed up a batch of glaze that we all love....EG-84 from CM =
article with a lot of recipes given by Woody Hughes. After firing, the =
pieces continue to form white powdery spots on the surface and have to =
be washed every few days.....I tried it in the first place because it =
only has 8.5% imported lithium...other things are available here =20
The recipe is
Baking soda 30.5
Lithium carbonate 8.5
Kaolin 22.5
Flint 38.5
Add tin oxide 5%
copper oxide 2.5
bentonite 1%
What would make the white powder after firing...same powdery results =
whether 06,04, over or underfired...I have only been working with and =
making low fire glazes for a year...never had this happen with =
stoneware...can someone tell me what's going on with it? Thanks so =
much, Melinda in Guatemala
Ababi on thu 15 mar 01
This is very simple the huge amount of soda bicarbonate. I have a recipe
with40%, and the sodium leaches terribly
Ababi Sharon
ababisha@shoval.ardom.co.il
http://members4.clubphoto.com/ababi306910/
----- Original Message -----
From: "Ron Collins"
To:
Sent: Thursday, March 15, 2001 9:35 PM
Subject: unusual glaze happening
I recently mixed up a batch of glaze that we all love....EG-84 from CM
article with a lot of recipes given by Woody Hughes. After firing, the
pieces continue to form white powdery spots on the surface and have to be
washed every few days.....I tried it in the first place because it only has
8.5% imported lithium...other things are available here
The recipe is
Baking soda 30.5
Lithium carbonate 8.5
Kaolin 22.5
Flint 38.5
Add tin oxide 5%
copper oxide 2.5
bentonite 1%
What would make the white powder after firing...same powdery results whether
06,04, over or underfired...I have only been working with and making low
fire glazes for a year...never had this happen with stoneware...can someone
tell me what's going on with it? Thanks so much, Melinda in Guatemala
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