Jeff Tsai on sun 20 jan 02
You'll have to retest this as my notebook with all the notes on this glaze
are missing, but here it is:
6.25% OM-4 Ball
76.80% Cedar Heights Redart
16.95% Flint
14% Cobalt Carb
14% Copper carb
64% Manganese Diox
I stopped using this glaze because of it's expense. It's also not the most
wonderful glaze to apply. I painted it on, too thin and it's black, too thick
and I mean real thick, and the manganese might start to bubble in a heavily
reduced atmosphere.
-jeff
Ceramic Design Group on sun 20 jan 02
on 1/20/02 8:08 AM, Jeff Tsai at DemJeffHQ@AOL.COM wrote:
> You'll have to retest this as my notebook with all the notes on this glaze
> are missing, but here it is:
>
> 6.25% OM-4 Ball
> 76.80% Cedar Heights Redart
> 16.95% Flint
>
> 14% Cobalt Carb
> 14% Copper carb
> 64% Manganese Diox
>
> I stopped using this glaze because of it's expense. It's also not the most
> wonderful glaze to apply. I painted it on, too thin and it's black, too thick
> and I mean real thick, and the manganese might start to bubble in a heavily
> reduced atmosphere.
Personally I would stay away from this glaze like the plague. This glaze
should be never used. Just look at the percentage of manganese dioxide and
copper carb in a "glaze base" that is ever so dubious even without the
effort of putting into Insight or Hyperglaze.
Please lets not make a habit of posting such mis-formulations on this list.
Jonathan
Jonathan Kaplan, president
Ceramic Design Group
PO Box 775112
Steamboat Springs CO 80477
voice and fax 970 879-9139
info@ceramicdesigngroup.net
Plant Location:
1280 13th Street Unit 13
Steamboat Springs CO 80487
(please use this address for all deliveries via UPS, comman carrier, Fed Ex,
etc.)
"Custom design and manufacturing for the ceramic arts, giftware and pottery
industries. Molds, models, and tooling for slip casting, jiggering and
hydraulic pressing. Consultation on clay and glaze formulation, production
systems,firing, and kilns.
Richard Aerni on sun 20 jan 02
Don't really want to be the glaze police here, but note the _64%_ Manganese
Dioxide in the recipe. If you don't have adequate ventilation around your
kiln, or if you intend the work for any kind of functionality, I'd think
long and hard before risking your health, and your customers', with this
glaze.
Richard Aerni
Bloomfield, NY
----- Original Message -----
> You'll have to retest this as my notebook with all the notes on this glaze
> are missing, but here it is:
>
> 6.25% OM-4 Ball
> 76.80% Cedar Heights Redart
> 16.95% Flint
>
> 14% Cobalt Carb
> 14% Copper carb
> 64% Manganese Diox
>
> I stopped using this glaze because of it's expense. It's also not the most
> wonderful glaze to apply. I painted it on, too thin and it's black, too
thick
> and I mean real thick, and the manganese might start to bubble in a
heavily
> reduced atmosphere.
>
> -jeff
.com.
>
Jocelyn McAuley on sun 20 jan 02
> Personally I would stay away from this glaze like the plague. This glaze
> should be never used. Just look at the percentage of manganese dioxide and
> copper carb in a "glaze base" that is ever so dubious even without the
> effort of putting into Insight or Hyperglaze.
>
> Please lets not make a habit of posting such mis-formulations on this list.
Jonathan,
why is this being labeled as a "mis-formulation", and why shouldn't it be
posted? Is it the lack of toxicity warning with the posted recipe that
has gotten your interest?
thanks
--
Jocelyn McAuley ><<'> jocie@worlddomination.net
Eugene, Oregon
http://www.ceramicism.com
Jeff Tsai on tue 22 jan 02
Ivor Wrote:
Lets be honest about this stuff.
It is not a glaze.
It may provide a highly decorative surface but it is not a glaze.
It may stick like the proverbial and be equally as bright when pasted on a barn door but it still not a glaze. And as you say, it will probably be unstable in most user conditions.
Best regards,
Ivor.
I have to admit I dread almost ever disagreeing with people on this list as I have a rather limited experience in comparison to most of them. Glazes, especially, are not my area of expertise (or even mediocritise). I also have tried not to answer on list responses to this glaze other than my apology for my mistake which in itself I was unsure of because I didn't want to seem like I was defending why I put it online for any reason.
Honestly, I don't even like or use this glaze, and I'm willing to admit of lot of its faults. It applies badly, it can bubble, it can run, it is a health hazard and not safe without proper safety precautions for mixing or firing and definitely not for food. It probably leaches, it probably doesn't "fit" well, there's probably some instability to it otherwise as well. But I can't understand why it wouldn't be considered a glaze.
I can understand why no one would use it for a dish. but as far as I know, and I have learned humility in having been often corrected throughout my life and if I'm wrong, this occassion is no exception, a glaze is basically the same oxides as in a clay added with a fluxing agent to melt at a particular temperature. This glaze has those components and I think is categorically a glaze, a bad one, but a glaze.
I don't know that glaze is limited to shiney surfaces, or food safe, or colorful, or heigenic or safe. I'm not defending the use of this glaze...I hope I've made this clear, just that it still is a glaze even if no production potter would use it.
-jeff
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