Ingeborg Foco on tue 4 sep 01
Dear Ron,
=20
=20
I am not presently subscribed to the list but hope this will be posted =
on my behalf.=20
=20
A very long time ago, you revised Pete's Cranberry to lower expansion =
in hopes of eliminating the crazing if I was willing to post the results =
to the group. I have a valid excuse for taking so very long to test the =
second revision but will spare you the sorry tale. By now most of you =
have probably moved on to other things but a promise is a promise and =
here are the results:
All glazes were fired to Cone 10 in a reduction atmosphere
#204=20
G200 -42.0
3123 - 18
Whiting - 9.5
EPK - 13.5
Silica - 17.0=20
Total - 100.0 plus 0.25 Copper carb and 3.0 tin
#205
G200 - 40.0
3134 - 17.5
Wollastonite - 13.0
OM #4 20.5
Silica - 9.0
total - 100 plus tin and copper carb same as above.
#204 Results: =20
The upright samples as well as flat tiles have a smooth glossy surface =
free from visible crazing. The color is a bright red with depth, =
similar to an oil spot glaze. Where thick and pooled on upright tiles, =
large oil spots that are surrounded by threads of green/brown. Several =
samples showed dark maroon within the oil spots.=20
It is an attractive red but different from the original Pete's =
Cranberry.
#205 Results:
Very similar in color to #204 Flat tiles have less depth and one shows =
crazing albeit very large veins.
#206 Results:
I took #204 & #205 and mixed them together and found samples to be =
identical to #204 and #205 =20
After the freeze and thaw test all samples are crazed. It is not easy =
to see but the lines are visible with a magnifying glass, good lighting =
and or good eye sight. All of the crazing is very large instead of the =
small tight lines of the original glaze. I would say the glaze is much =
improved in that area but also different. I think it is still an =
attractive glaze.
I also tested David Hendley's "Simply Red" to see how it compared to the =
above samples. Simply Red is a very stable glaze. The color is more of =
a pale raspberry with gray flecks and undertones. As far as I could =
tell, it did not craze. It is a very nice copper red but somehow does =
not have the, well, vavavoom that Pete's cranberry packs.
I should mention that my clay body is an iron bearing gray stoneware =
consequently it does not show up any copper red glaze quite as nicely as =
a white body would.
Sincerely=20
Ingeborg
Ron Roy on wed 5 sep 01
So - the questions are - do you want me to do two more and get rid of the
crazing? and - the frit in #204 is it 3124?
If the crazing lines are far apart it means it will take a fairly small
adjustment to eliminate it.
RR
>I am not presently subscribed to the list but hope this will be posted on
>my behalf.
>
> A very long time ago, you revised Pete's Cranberry to lower expansion in
>hopes of eliminating the crazing if I was willing to post the results to
>the group. I have a valid excuse for taking so very long to test the
>second revision but will spare you the sorry tale. By now most of you
>have probably moved on to other things but a promise is a promise and
>here are the results:
>
>All glazes were fired to Cone 10 in a reduction atmosphere
>
>#204
>
>G200 -42.0
>3123 - 18
>Whiting - 9.5
>EPK - 13.5
>Silica - 17.0
>Total - 100.0 plus 0.25 Copper carb and 3.0 tin
>
>
>#205
>
>G200 - 40.0
>3134 - 17.5
>Wollastonite - 13.0
>OM #4 20.5
>Silica - 9.0
>total - 100 plus tin and copper carb same as above.
>
>#204 Results:
>
>The upright samples as well as flat tiles have a smooth glossy surface
>free from visible crazing. The color is a bright red with depth, similar
>to an oil spot glaze. Where thick and pooled on upright tiles, large oil
>spots that are surrounded by threads of green/brown. Several samples
>showed dark maroon within the oil spots.
>It is an attractive red but different from the original Pete's Cranberry.
>
>#205 Results:
>
>Very similar in color to #204 Flat tiles have less depth and one shows
>crazing albeit very large veins.
>
>#206 Results:
>
>I took #204 & #205 and mixed them together and found samples to be
>identical to #204 and #205
>
>After the freeze and thaw test all samples are crazed. It is not easy to
>see but the lines are visible with a magnifying glass, good lighting and
>or good eye sight. All of the crazing is very large instead of the small
>tight lines of the original glaze. I would say the glaze is much improved
>in that area but also different. I think it is still an attractive glaze.
>
>
>I also tested David Hendley's "Simply Red" to see how it compared to the
>above samples. Simply Red is a very stable glaze. The color is more of a
>pale raspberry with gray flecks and undertones. As far as I could tell,
>it did not craze. It is a very nice copper red but somehow does not have
>the, well, vavavoom that Pete's cranberry packs.
>
>I should mention that my clay body is an iron bearing gray stoneware
>consequently it does not show up any copper red glaze quite as nicely as a
>white body would.
>
>Sincerely
>
>Ingeborg
>
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Ron Roy
RR# 4
15084 Little Lake Rd..
Brighton,
Ontario, Canada
KOK 1H0
Residence 613-475-9544
Studio 613-475-3715
Fax 613-475-3513
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