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problem glazes and ghastly borate

updated wed 30 apr 97

 

Karl P. Platt on sun 20 apr 97




Kill your television
> ....after I thoroughly mix.... little floating lumps that are not seen
when mixed,...stick to my hand. I have pots with little lumps.
> It's nothing that I can rub in and smooth out....What is happening? I
put a little epsom salts in one but it has not helped. One recipe includes
> G.Borate.....The other one has g.borate, silica, zircopax. Could it
be the water?

Could it be the Ghastley Borate?

KPP -- STILL wondering why anyone uses this stuff. Is it cheap or what?

Craig Martell on tue 22 apr 97

At 10:23 AM 4/20/97 EDT, Karl Platt wrote:
>----------------------------Original message----------------------------

>Could it be the Ghastley Borate?
>
>KPP -- STILL wondering why anyone uses this stuff. Is it cheap or what?


Yes, Gerstley Borate is cheaper than Boron frits and easier in most cases to
calculate into a glaze. I've used this source of Boron for many years and
have found it to be a very useful material. Sure, it can cause problems and
has it's own idiosyncrasies but in most cases is of benefit if a glaze calls
for Boron. It's a lot easier to deal with than Magnesium Carb.!!

Maybe you should make some pots and try a variety of glazes with and without
Gerstley Borate in order to get an idea of why anyone would use GB. Whether
or not this stuff is referred to as Gerstley or "Ghastley", I'll keep using
it because, in the main, it works pretty well.

Regards, Craig Martell-Oregon

Marget and Peter Lippincott on wed 23 apr 97

Karl P. Platt wrote:
>
> ----------------------------Original message----------------------------
>
> Kill your television
> > ....after I thoroughly mix.... little floating lumps that are not seen
> when mixed,...stick to my hand. I have pots with little lumps.
> > It's nothing that I can rub in and smooth out....What is happening? I
> put a little epsom salts in one but it has not helped. One recipe includes
> > G.Borate.....The other one has g.borate, silica, zircopax. Could it
> be the water?
>
> Could it be the Ghastley Borate?
>
> KPP -- STILL wondering why anyone uses this stuff. Is it cheap or what?
Karl:
I assume you are advocating use of a boron frit. Which one or ones work
the best, and what proceedure should I use to determine the amount to
sub for the GB. Don't frits have other stuff in them which would have
to be taken into account too?
For the glaze gurus --it there a simple way to make the substitution
with a certain frit?
Peter Lippincott, the mudpuppy, in Arkansas

Tony Hansen on thu 24 apr 97

> Don't frits have other stuff in them which would have
> to be taken into account too..
> is there a simple way to make the substitution
> with a certain frit?

Visit the web page at
www.ceramicsoftware.com/magic/cornwall.htm
for an example of how to substitute a mix of other materials
for cornwall stone. The same principles apply to frits.

It is even simpler to just introduce the new frit, then look
at the formula in a ceramic calculation program and change the
amounts of other materials in the recipe to compensate formula
changes imposed by the new frit.

--
=================================================================
Tony Hansen, IMC thansen@mlc.awinc.com
INSIGHT5/Magic of Fire II demos at www.ceramicsoftware.com