Valerie Hawkins on mon 29 apr 02
I'm just wondering if anyone could predict the future of the manufactured
borates. (laguna borate, cadycal, etc). I rarely see a glaze recipe
incorporating these products so I'm wondering if their future is secure.
Can I develop glazes with these materials or would it be best to just use
FF3134?
Valerie
Charlotte
John Hesselberth on mon 29 apr 02
on 4/29/02 9:24 AM, Valerie Hawkins at vhawkins1@CAROLINA.RR.COM wrote:
> I'm just wondering if anyone could predict the future of the manufactured
> borates. (laguna borate, cadycal, etc). I rarely see a glaze recipe
> incorporating these products so I'm wondering if their future is secure.
> Can I develop glazes with these materials or would it be best to just use
> FF3134?
>
> Valerie
> Charlotte
Hi Valerie,
All you will get on this are opinions because no one knows for sure. So I'll
give you mine. I would not use one of the so-called replacement products. I
won't even spend time testing them.
Here is why. Gerstley Borate became uneconomical to produce--either the mine
was giving out or the market was too small--I don't think there was ever a
clear answer to that--but the bottom line is the producer could no longer
make a satisfactory profit. Now there are about 4 products trying to
replace that one product. What can their economics be?? Almost certainly
one or more of them will drop out after a couple years. Which one? The one
you used to develop your new line of glazes, of course. One of the
corollaries of Murphy's Law, I think.
Plus the market is no longer as big as it was. Many people have gone to
frits already. Since frits are used by industry the volume production of
them is large and they are much more likely to be around for a long time.
All the boron in the glazes in our new book is sourced from frits. We
didn't even consider developing glazes with the new products. And so far we
haven't found a single thing we wanted to do that we couldn't with frits.
Just one opinion,
John
web sites: http://www.masteringglazes.com and http://www.frogpondpottery.com
EMail: john@frogpondpottery.com
"Pots, like other forms of art, are human expressions: pleasure, pain or
indifference before them depends upon their natures, and their natures are
inevitably projections of the minds of their creators." Bernard Leach, A
Potter's Book.
John Hesselberth on wed 1 may 02
on 4/30/02 12:35 AM, Paul Lewing at PJLewing@WORLDNET.ATT.NET wrote:
> I do know that I have some recipes that I've
> never been able to make look as good with frits as they did with GB.
Hi Paul,
One of the things Ron and I found to be important when trying to substitute
a frit for GB is to simultaneously replace any EPK with ball clay--I use
OM-4. I also tend to favor 3134 as my source of boron since it has no
alumina. The net effect of these two changes is to allow you to put quite a
bit more clay into the recipe while holding alumina constant. Since silica
is normally added to most recipes you can reduce the silica level to hold it
constant. That added clay--in the form of ball clay--seems to replace quite
a bit, if not all, of the "magic" of GB.
This is what I did in developing our Raspberry recipe. When I tried to take
a typical GB-based chrome/tin red recipe and substitute a frit holding all
other ingredients the same--adjusting only the amounts for constant unity--I
didn't do very well. When Ron suggested replacing the EPK with ball
clay--bingo!! I think a number of people who have tried Raspberry will
agree it is a pretty nice chrome/tin red.
Give the 3134/OM-4 technique a try and see if it works for you.
Regards,
John
web sites: http://www.masteringglazes.com and http://www.frogpondpottery.com
EMail: john@frogpondpottery.com
"Pots, like other forms of art, are human expressions: pleasure, pain or
indifference before them depends upon their natures, and their natures are
inevitably projections of the minds of their creators." Bernard Leach, A
Potter's Book.
william schran on thu 2 may 02
John wrote: "Give the 3134/OM-4 technique a try and see if it works
for you." This in reference to subbing 3134 for gerstley borate and
subbing OM4 for kaolin.
John - I have "Mastering Cone 6 Glazes" and have been pleased with
the glazes. Got good results with Raspberry.
Do you believe the 3134/OM4 substitution would work well for raku
temperature glazes also?
I used Dal Tile Frit 439 and 15-20% EPK last year for raku glaze base
- worked extremely well until it was discovered the frit was soluble.
The frit has been re-formulated but it's availability is in question.
Bill
John Hesselberth on thu 2 may 02
on 5/2/02 9:40 AM, william schran at wschran@EROLS.COM wrote:
> John wrote: "Give the 3134/OM-4 technique a try and see if it works
> for you." This in reference to subbing 3134 for gerstley borate and
> subbing OM4 for kaolin.
>
> John - I have "Mastering Cone 6 Glazes" and have been pleased with
> the glazes. Got good results with Raspberry.
> Do you believe the 3134/OM4 substitution would work well for raku
> temperature glazes also?
>
> I used Dal Tile Frit 439 and 15-20% EPK last year for raku glaze base
> - worked extremely well until it was discovered the frit was soluble.
> The frit has been re-formulated but it's availability is in question.
>
Hi Bill,
I certainly think it is worth a try. I haven't worked in raku for a few
years so I haven't tested it there. If you are into glaze calc give it a
try. If you are not send me a recipe you want to convert from GB--I'll have
a go at the calculation and send it back to you to test.
John
Web sites: http://www.masteringglazes.com and http://www.frogpondpottery.com
Email: john@frogpondpottery.com
"The life so short, the craft so long to learn." Chaucer's translation of
Hippocrates, 5th cent. B.C.
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