Ingeborg Foco on mon 31 mar 03
Hi,
I have done three days of testing trying to come up with colors that will
work with my tile mural. This morning I unloaded more test samples and
things are getting closer.The tile colors were somewhat blotchy but I
attribute that to not having screened the samples.
I went to do further tests with the mixed glazes but found all ten samples
solid in their styrofoam cup. Solid like rock. It is as if some kind of
catalyst hardened the glaze overnight.
Really bizarre. Adding water seemed not to do much at least not in the
short term. I took one sample and heated it and was able to melt it back
down to a liquid state. I left the rest to see if water would soften them in
the long term.
Has anyone ever had this happen and if so how can it be prevented. The base
recipe is :
Spodumene 50
Gerstley Borate 30
Flint 20
Zircopax 10
then the various Mason Stains from 2% - 10%.
Thanks in advance for any insight.
Ingeborg
the Potter's Workshop & Gallery
P.O. Box 510
3058 Stringfellow Road
St. James City, Florida 33956
239-283-2775
Tony Hansen on mon 31 mar 03
That is a lot of spodumene and if I remember correctly
that stuff likes to settle solid.
I think it would be better to use a fritted glaze
for low fire, one that has a high and low expansion
frit so you can juggle their amounts to tune the
thermal expansion you need. Check this page:
http://digitalfire.ab.ca/cermat/education/226.php
> Hi,
> I have done three days of testing trying to come up with colors that will
> work with my tile mural. This morning I unloaded more test samples and
> things are getting closer.The tile colors were somewhat blotchy but I
> attribute that to not having screened the samples.
> I went to do further tests with the mixed glazes but found all ten samples
> solid in their styrofoam cup. Solid like rock. It is as if some kind of
> catalyst hardened the glaze overnight.
> Really bizarre. Adding water seemed not to do much at least not in the
> short term. I took one sample and heated it and was able to melt it back
> down to a liquid state. I left the rest to see if water would soften them in
> the long term.
> Has anyone ever had this happen and if so how can it be prevented. The base
> recipe is :
> Spodumene 50
> Gerstley Borate 30
> Flint 20
> Zircopax 10
> then the various Mason Stains from 2% - 10%.
> Thanks in advance for any insight.
========
Tony Hansen, Digitalfire Corporation, http://digitalfire.com
Tony Hansen on mon 31 mar 03
What frits do you have?
> Thanks so much for the info. I looked at all of the applicable information
> on your site. Normally I work in cone 10 reduction so this is all new to
> me. The Mason stain rep suggested using 78% frit 3124 and 12% kaolin. I
> didn\'t have any 3124 on hand and thought I would work with this recipe given
> to me. (I have ample supply of those ingredients) Supposedly it was, I
> think Pete Pinnel\'s but I\'m not sure now...at any rate, someone a lot more
> famous than me. So I figured it has to be a winner. Wrong obviously.
> I guess I will bite the bullet and have some proper frit shipped in. I\'m
> not moving a head on this project this way. I\'m in the middle of now where
> and everything has to be shipped in at no small expense.
> Again, thank you.
> Sincerely,
>
> Ingeborg
> the Potter\'s Workshop & Gallery
> P.O. Box 510
> 3058 Stringfellow Road
> St. James City, Florida 33956
> 239-283-2775
>
> > That is a lot of spodumene and if I remember correctly
> > that stuff likes to settle solid.
> > I think it would be better to use a fritted glaze
> > for low fire, one that has a high and low expansion
> > frit so you can juggle their amounts to tune the
> > thermal expansion you need. Check this page:
> > http://digitalfire.ab.ca/cermat/education/226.php
> >
>
>
========
Tony Hansen, Digitalfire Corporation, http://digitalfire.com
Ron Roy on thu 3 apr 03
Hi Ingeborg,
Hold up - the expansion of your glaze is way low for any kind of normal
pottery clay - look for shivering. Part of the problem is no clay in the
recipe - I have reformed it to raise the expansion and added clay and
bentonite to stop the settling.
Spod - 25.0
G200 - 25.0 (you can use Custer)
Frit 3134 - 38.0
EPK - 8.0
Silica - 4.0
Zircopax - 10.0
Bentonite - 2.0
Total 112.0
Do I assume this is for cone 6? I can make it a better glaze but you need
to test it first and do the freezer test to see if there is any fit
problem.
Make sure you screen all through 80M - twice!
RR
>I have done three days of testing trying to come up with colors that will
>work with my tile mural. This morning I unloaded more test samples and
>things are getting closer.The tile colors were somewhat blotchy but I
>attribute that to not having screened the samples.
>
> I went to do further tests with the mixed glazes but found all ten samples
>solid in their styrofoam cup. Solid like rock. It is as if some kind of
>catalyst hardened the glaze overnight.
>Really bizarre. Adding water seemed not to do much at least not in the
>short term. I took one sample and heated it and was able to melt it back
>down to a liquid state. I left the rest to see if water would soften them in
>the long term.
>
>Has anyone ever had this happen and if so how can it be prevented. The base
>recipe is :
>
>Spodumene 50
>Gerstley Borate 30
>Flint 20
>Zircopax 10
>
>then the various Mason Stains from 2% - 10%.
>
>Thanks in advance for any insight.
>
>
>Ingeborg
>the Potter's Workshop & Gallery
>P.O. Box 510
>3058 Stringfellow Road
>St. James City, Florida 33956
>
>239-283-2775
>
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Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
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