will edwards on sun 10 sep 00
In reference to Mary Simmons reporting on Murrays borate I would like to =
ask
everyone to please post anything they have on the new uses of any of the
substitute GB compounds.
I compiled some information that isn't very appealing to the readers rega=
rding
what testing I have done on certain replacements. However not to confuse =
the
scientific data with observational results I can say they are a mass
difference in specifics regarding the various stages I have tested glazes=
in
using these replacements.
First - MB proved to over-flux the glaze on an equal basis as perscribe b=
y the
marketer's of the product. I took pictures of several different firings a=
t
different temperatures to show the vast changes along side those with equ=
al
parts of GB and in no way could they compare.
I was also told by another on this group it will work. That was all I was=
told. (Mel) Give me some examples regarding this if you will? I was told =
to
include x amount of bentonite in the glaze if the glaze didn't contain en=
ough
bentonite/clays in the mix.
No scale I used would allow me to formulate with enough bentonite to disp=
lace
the problem without completely altering any of the one to one ways of wor=
king
this out. What I am saying is they were more than enough clay in the mix =
to
start with in one particular recipe and then adding additional bentonite
didn't resolve anything either. Changed the pattern and used another set =
of
recipes and another kiln with digital controls and a down-draft fired to =
^6
Oxidation and had the same problem once more. Fluid glaze out of balance
running like molten lava.
What we want to know (especially me) is who has had results using what bo=
rate
compounds and how did they obtain them if using the MB or LB. Also perso=
nally
I am one proud person to shed myself of all GB related glazes knowing wha=
t I
do now. The future will hold a better place for replacments only if and w=
hen
each person is willing to fully part with complete analysis of both the r=
ecipe
for the glaze or in the least an accurate accounting of the materials of =
the
compound in order to try and work out a way to make it work.
So far I have not used any more of the 100 pd's of this stuff we bought. =
I
have been working night and day on my own replacing every one of my glaze=
s one
by one using techniques that are scientific but also relies on visual res=
ults
in the end firing. I have matched the glaze's of many of my recipes with
touching any GB or MB but would be tempting to have a frit that has a sim=
ilar
trait as the old stand-by GB.
I never take someones word for anything and this one time I did I made th=
e
mistake of losing over 20 gallons of various glazes. Many containing expe=
nsive
oxides. (My fault?) Maybe.... Also someone elses fault for marketing a
material without completely disclosing all the information needed for
calculating a balanced glaze due to lack of information somewhere along t=
he
path to the market place. Does anyone here including KPS have the full na=
me
and information regarding the manufacturer of Murray's Borate so I can di=
scuss
the exact values on a one to one basis? Less the bentonite of course...
William Edwards
____________________________________________________________________
Get free email and a permanent address at http://www.netaddress.com/?N=3D=
1
Mert & Holly Kilpatrick on mon 11 sep 00
I have tested Berry Rust, Maple Syrup, the Eggplant Purple base with several
colorants, Phoenix and AACC #2 Floating Blue to replace the Gerstley Borate.
I have completed some tests, have more to do. I am finding that each glaze
is different, there isn't one solution for all the glazes. For the
Gillespie, I subbed 1 for 1 with GB, because I don't have the analysis. For
Laguna and Murrays borate and Frit 3134 I used GlazeChem to reformulate the
glaze as close as possible to the GB-version formula. Of course, it is all
experimental because I don't know how closely my GB analysis was to my
actual GB.
The Berry Rust seems much the same on test cups with Laguna and Gillespie
borate, with Murrays and Frit 3134 it hardened so much in the containers I
didn't even bother to test it. Maple Syrup was much better with Gillespie,
the others were very milky. The Eggplant Purple base seems to do well with
Frit 3134. I tried Phoenix with Gillespie and it was a failure, I will try
others. So far I think I like the Floating Blue with Laguna, which makes a
different glaze really, but I need to run through the Floating Blue tests
again, I tried to do too much on each test cup, with the result that I can't
tell what's what.
It's time-consuming! I would also like to get some Cady-cal and if I had
more time, I would like to ball mill some ulexite and try Tony Hansen's
concoction.
Holly, in PA
----- Original Message -----
From: will edwards
....What we want to know (especially me) is who has had results using what
borate
compounds and how did they obtain them if using the MB or LB.....
William Edwards
Norman van der Sluys on mon 11 sep 00
One problem is that Gerstley Borate has been used in more than one way. For
example, I have recipes using it as a secondary flux in mid-range stoneware glazes
(reduction.) I also do raku and most of my glazes use 80% GB and are fired to
around 1800 oF. To expect a substitute material to behave the same (as if GB
behaved the same from batch to batch!) is asking too much. The material you want
is not Laguna Borate or Gillespie Borate or any other Borate, but
good old Gerstley Borate, of a composition consistent with that used in the
original formulation of the glaze. It aint gonna happen!
Sometimes the tuition at the school of hard knocks is quite high, and it is irksome
when we get that unexpected "refresher course." The fact is, we must always test,
test, test.
will edwards wrote:
> In reference to Mary Simmons reporting on Murrays borate I would like to ask
> everyone to please post anything they have on the new uses of any of the
>
> First - MB proved to over-flux the glaze on an equal basis as perscribe by the
> marketer's of the product. I took pictures of several different firings at
> different temperatures to show the vast changes along side those with equal
> parts of GB and in no way could they compare.
> Changed the pattern and used another set of
> recipes and another kiln with digital controls and a down-draft fired to ^6
> Oxidation and had the same problem once more. Fluid glaze out of balance
> running like molten lava.
>
--
Norman van der Sluys
by the shore of Lake Michigan
Tom Buck on wed 13 sep 00
Well, Mr Taylor, your comments on Gerstley Borate are not correct in
total.
Gerstley Borate, an ore mined (until this year) in California,
USA, was a mix of ulexite (NaCaB5O9.8H2O) and colemanite (Ca2B6O11.5H2O),
plus some limestone, plus some shale/clay, plus some unknown (ie,
unanalyzed for) "inerts".
This odd combination gave Raku potters some interesting results
but upset mainline potters because of its erratic behaviour. It offgassed
hugely, as you suggested, between 28 and 34% of its total weight went up
the flue.
In North America, there is a major push to replace the GB, and
several companies offer new materials. See my brief report elsewhere on
Clayart, and go to http://www.gerstleyborate. com/
for full details.
til later. peace. Tom B.
Tom Buck )
tel: 905-389-2339 (westend Lake Ontario, province of Ontario, Canada).
mailing address: 373 East 43rd Street,
Hamilton ON L8T 3E1 Canada
Paul Taylor on wed 13 sep 00
Dear ALL
To add to Normans Post.
I have a suspicion Gerstely Borate has a considerable loss on ignition 20%
water off in the atmosphere unless the substitutes have a similar loss they
are not the same - Gerstely borate is a Colemanite I think
2CaO.3B2O3.2H2O.
Even if the manufactured substitutes have the same chemicals in them they
will not be in the same structure melting at the same rate as a natural frit
(Collins dictionary) that has a well defined structure. I also suspect that
the water in the structure adds to the melting process. This the substitutes
can not emulate.
Even so all is not lost. The substitutes should eventually give similar
glazes with greater reliability but with considerable adjustments to the
recipe.
Other Colemanites do exist but they too will not be able to be
substituted directly weight for weight. Allowances will have to be made by
adding whiting or a calcium borate frit.
Peoples Experience seems to back my reasoning. Am I wrong?
-- Regards Paul Taylor.
Westport Pottery, Liscarney, County Mayo. Ireland.
http://www.anu.ie/westportpottery/
Ps to all. Please paragraph your posts and put a blank line in between the
paragraphs. I have great difficulty reading large blocks of type from a
screen.
> From: Norman van der Sluys
> Reply-To: Ceramic Arts Discussion List
> Date: Mon, 11 Sep 2000 08:09:09 -0400
> To: CLAYART@LSV.CERAMICS.ORG
> Subject: Re: Borates
>
> One problem is that Gerstley Borate has been used in more than one way. For
> example, I have recipes using it as a secondary flux in mid-range stoneware
> glazes
> (reduction.) I also do raku and most of my glazes use 80% GB and are fired to
> around 1800 oF. To expect a substitute material to behave the same (as if GB
> behaved the same from batch to batch!) is asking too much. The material you
> want
> is not Laguna Borate or Gillespie Borate or any other Borate,
> but
> good old Gerstley Borate, of a composition consistent with that used in the
> original formulation of the glaze. It aint gonna happen!
>
> Sometimes the tuition at the school of hard knocks is quite high, and it is
> irksome
> when we get that unexpected "refresher course." The fact is, we must always
> test,
> test, test.
>
> will edwards wrote:
>
>> In reference to Mary Simmons reporting on Murrays borate I would like to ask
>> everyone to please post anything they have on the new uses of any of the
>>
>> First - MB proved to over-flux the glaze on an equal basis as perscribe by
>> the
>> marketer's of the product. I took pictures of several different firings at
>> different temperatures to show the vast changes along side those with equal
>> parts of GB and in no way could they compare.
>> Changed the pattern and used another set of
>> recipes and another kiln with digital controls and a down-draft fired to ^6
>> Oxidation and had the same problem once more. Fluid glaze out of balance
>> running like molten lava.
>>
>
> --
> Norman van der Sluys
>
> by the shore of Lake Michigan
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
Sharon31 on thu 14 sep 00
Hello Tom!
I ask myself, I know it is basically bad to use soluble materials, I use
them in small amounts, when I cannot connect directly between a given recipe
and my boron or K2O sources.
In Don Goodrich, there is a recipe:
**********************************************
GERSTLEY BORATE SUBSTITUTION
Boric acid 90.25 (soluble)
Whiting 48.69
from Brian Harper
****************************************************
What do you think about it? As a last solution?
Thanks
Ababi Sharon
sharon@shoval.org.il
http://www.milkywayceramics.com/cgallery/asharon.htm
----- Original Message -----
From: Tom Buck
To:
Sent: Thursday, September 14, 2000 05:56
Subject: Re: Borates
> Well, Mr Taylor, your comments on Gerstley Borate are not correct in
> total.
> Gerstley Borate, an ore mined (until this year) in California,
> USA, was a mix of ulexite (NaCaB5O9.8H2O) and colemanite (Ca2B6O11.5H2O),
> plus some limestone, plus some shale/clay, plus some unknown (ie,
> unanalyzed for) "inerts".
> This odd combination gave Raku potters some interesting results
> but upset mainline potters because of its erratic behaviour. It offgassed
> hugely, as you suggested, between 28 and 34% of its total weight went up
> the flue.
> In North America, there is a major push to replace the GB, and
> several companies offer new materials. See my brief report elsewhere on
> Clayart, and go to http://www.gerstleyborate. com/
> for full details.
> til later. peace. Tom B.
>
> Tom Buck )
> tel: 905-389-2339 (westend Lake Ontario, province of Ontario, Canada).
> mailing address: 373 East 43rd Street,
> Hamilton ON L8T 3E1 Canada
>
>
____________________________________________________________________________
__
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
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