martin howard on thu 16 mar 00
We usually receive recipes in postings.
But for those of us away from the USA, formulae are usually the most useful.
We do not necessarily have access or wish to use the raw materials mentioned
in the recipes, wonderful as they may be.
We prefer to use our raw materials, because we know them, and can then make
use of unity formulae more simply than recipes.
Do I speak for others in the UK and elsewhere with access to glaze software?
Martin Howard
Webb's Cottage Pottery
Woolpits Road
Great Saling
BRAINTREE
Essex CM7 5DZ
01371 850 423
martin@webbscottage.co.uk
www.webbscottage.co.uk Should be ready for 2000 :-) or 2001
David Hendley on fri 17 mar 00
Martin, I of course agree with you that it's nice to have the
formula of a glaze posted as well the recipe. The truth, however,
is that a majority of people who do ceramic work do not
deal in glaze formulae because they don't even understand
the difference, much less how a formula relates to a recipe.
If you will look back over suggestions and discussions of
glazes on Clayart, you will find that the real knowledgeable
pros do include the formula as well as the recipe.
If you have a glaze calc program with a good data base of
materials, it is a simple matter to convert any recipe using
American ingredients into a formula. You can then design
a new glaze with the same formula, but with your own
desired ingredients.
--
David Hendley
Maydelle, Texas
hendley@tyler.net
http://www.farmpots.com/
----- Original Message -----
From: martin howard
To:
Sent: Thursday, March 16, 2000 11:36 AM
Subject: Recipes or Formulae
| ----------------------------Original message----------------------------
| We usually receive recipes in postings.
|
| But for those of us away from the USA, formulae are usually the most
useful.
| We do not necessarily have access or wish to use the raw materials
mentioned
| in the recipes, wonderful as they may be.
| We prefer to use our raw materials, because we know them, and can then
make
| use of unity formulae more simply than recipes.
|
| Do I speak for others in the UK and elsewhere with access to glaze
software?
|
| Martin Howard
| Webb's Cottage Pottery
| Woolpits Road
| Great Saling
| BRAINTREE
| Essex CM7 5DZ
| 01371 850 423
| martin@webbscottage.co.uk
| www.webbscottage.co.uk Should be ready for 2000 :-) or 2001
|
ferenc jakab on fri 17 mar 00
Martin,
recipes are fine here in Oz, we have access to many of the materials
mentioned. and access to formulae if not, our problem is with the clay
bodies mentioned since these are very different as yours must be too.
Feri.
David Hewitt on fri 17 mar 00
Martin,
I share your view that it is very desirable to have an analysis with a
recipe, provided that it is based on the analysis of the raw materials
used by the originator in that recipe. This certainly does help in the
'transporting' of glaze recipes.
It is, of course, also very important to have the recipe. An analysis
alone is not enough. It is very important to know the source of the
individual oxides in an analysis that the originator of the recipe has
used as this can significantly affect the finished glaze. Which feldspar
do you select? Do you source the MgO from dolomite, magnesium carbonate
or talc? Which frit was used? It is also important to know the type of
clay body used by the originator, and this is also not often included.
'Transporting' glaze recipes is not easy and I have tried to cover many
of the potential problem areas by an article on my web site under this
heading.
David
In message , martin howard writes
>----------------------------Original message----------------------------
>We usually receive recipes in postings.
>
>But for those of us away from the USA, formulae are usually the most useful.
>We do not necessarily have access or wish to use the raw materials mentioned
>in the recipes, wonderful as they may be.
>We prefer to use our raw materials, because we know them, and can then make
>use of unity formulae more simply than recipes.
>
>Do I speak for others in the UK and elsewhere with access to glaze software?
>
>Martin Howard
>Webb's Cottage Pottery
>Woolpits Road
>Great Saling
>BRAINTREE
>Essex CM7 5DZ
>01371 850 423
>martin@webbscottage.co.uk
>www.webbscottage.co.uk Should be ready for 2000 :-) or 2001
>
--
David Hewitt
madwa on sat 18 mar 00
Hi Martin
I concur absolutely with you re: unity formulae - if I am interested in any
of the recipes, I enter them in Matrix and make up my own recipe using raw
materials found in New Zealand. There are, however, several raw materials
used in the USA which are easily replaced by some raw materials here, in
which case there is no problem. Even so, I still enter the recipe into
Matrix to see if it's a recipe I'd really want to use, and to see if the
glaze would fit the clay body I use.
Sharry Madden
from Sweet New Zealand
John K Dellow on sun 19 mar 00
David Hendley wrote :-
If you have a glaze calc program with a good data base of
> materials, it is a simple matter to convert any recipe using
> American ingredients into a formula. You can then design
> a new glaze with the same formula, but with your own
> desired ingredients.
Unfortunately that does not always work. A friend in the IRC
"pottery chat " room gave me the recipe of his "Fairhope Rutile
Blue " glaze .
Using the known analysis of his raw materials using Insight I
recalculated to the current australian raw materials. I also made
up a test batch by a straight sub of aussie materials on a %
basses . Fired both and scanned the test pieces & sent to him.
The recalculated glaze was not correct and the straight % sub
looked to him to be very close to his original. Even thought my
recalculation was almost a perfect match and the % sub was quite
different, go figure !.
John Dellow "the flower pot man"
Home Page http://www.welcome.to/jkdellow
http://digitalfire.com/education/people/dellow/
Ron Roy on mon 20 mar 00
This is to the group John - I'm not saying this is what happened to you.
There is a bug in all this - we assume everyones analysis for any
particular material is the same or close to ours. Many texts and glazes
programs have incorrect analysis for some materials - I could use two
glaring examples - one from a book on glazes - with an incorrect frit
analysis and a calculation program that was shipped for years with an
incorrect analysis for Gerstley Borate.
Sometimes - when you check 2 or 3 books they all have the same mistake - it
means the authors have been using other books to get some of their
information.
In the end - the analysis used should be verified with the mine - the
company that mines g200 spar has a web page for instance - and you can get
that one and EPK there.
I make sure I have an analysis from the mine or frit maker - or check as
many sources as possible till I am as certain as I can be.
It is easy to type a wrong number in - check out any data base and you will
fine errors sooner or later.
And of course make sure you have an LOI and a program that will take it
into account.
Wish I had the time to check a few data bases - perhaps someone would be
willing to pay me to check theirs - then we could all get on the same page.
Forget I said that - who would want a job like that?
RR
>----------------------------Original message----------------------------
>David Hendley wrote :-
> If you have a glaze calc program with a good data base of
>> materials, it is a simple matter to convert any recipe using
>> American ingredients into a formula. You can then design
>> a new glaze with the same formula, but with your own
>> desired ingredients.
>
> Unfortunately that does not always work. A friend in the IRC
>"pottery chat " room gave me the recipe of his "Fairhope Rutile
>Blue " glaze .
> Using the known analysis of his raw materials using Insight I
>recalculated to the current australian raw materials. I also made
>up a test batch by a straight sub of aussie materials on a %
>basses . Fired both and scanned the test pieces & sent to him.
>The recalculated glaze was not correct and the straight % sub
>looked to him to be very close to his original. Even thought my
>recalculation was almost a perfect match and the % sub was quite
>different, go figure !.
>
>
> John Dellow "the flower pot man"
>Home Page http://www.welcome.to/jkdellow
>http://digitalfire.com/education/people/dellow/
Ron Roy
93 Pegasus Trail
Scarborough
Ontario, Canada
M1G 3N8
Evenings 416-439-2621
Fax 416-438-7849
David Hendley on mon 20 mar 00
Hey John -----
I know, I know, going from recipe, to formula, back to
recipe doesn't always work, but it's a good place to start.
As they say "Glazes don't travel well".
A real weak link for most people is that they don't keep
their materials data base up-to-date.
How, by the way, do you scan your glaze test pieces?
Can it be done with a scanner, or do you mean you have
a digital camera?
--
David Hendley
Maydelle, Texas
hendley@tyler.net
http://www.farmpots.com/
On the road to Denver by the time you read this!
Bring you rain gear to Denver - chance of rain all week.
----- Original Message -----
From: John K Dellow
To:
Sent: Sunday, March 19, 2000 10:49 AM
Subject: Re: Recipes or Formulae
| ----------------------------Original message----------------------------
| David Hendley wrote :-
| If you have a glaze calc program with a good data base of
| > materials, it is a simple matter to convert any recipe using
| > American ingredients into a formula. You can then design
| > a new glaze with the same formula, but with your own
| > desired ingredients.
|
| Unfortunately that does not always work. A friend in the IRC
| "pottery chat " room gave me the recipe of his "Fairhope Rutile
| Blue " glaze .
| Using the known analysis of his raw materials using Insight I
| recalculated to the current australian raw materials. I also made
| up a test batch by a straight sub of aussie materials on a %
| basses . Fired both and scanned the test pieces & sent to him.
| The recalculated glaze was not correct and the straight % sub
| looked to him to be very close to his original. Even thought my
| recalculation was almost a perfect match and the % sub was quite
| different, go figure !.
|
|
| John Dellow "the flower pot man"
| Home Page http://www.welcome.to/jkdellow
| http://digitalfire.com/education/people/dellow/
|
John K Dellow on tue 21 mar 00
To further elaborate on this thread , one needs to keep old
dated material definitions.
A problem here in australia for those who were potting in the
70's or are using recipes from that period or earlier is the
closing down of the Broken Hill feldspar mine. A new supply of
Potash Feldspar was sauced from Western australia which had a
very different analysis.
Australian potters can down load 2 of my TMT's for Insight from
my site at digitalfire ( the URL is at the bottom of this post) .
I complied 3 ,"pre 80's ,80's & 90's. Some of these analysis came
from books but most from Data sheets.
John
Ron Roy wrote:
>
> ----------------------------Original message----------------------------
> This is to the group John - I'm not saying this is what happened to you.
>
> There is a bug in all this - we assume everyones analysis for any
> particular material is the same or close to ours. Many texts and glazes
> programs have incorrect analysis for some materials - I could use two
> glaring examples - one from a book on glazes - with an incorrect frit
> analysis and a calculation program that was shipped for years with an
> incorrect analysis for Gerstley Borate.
>
> Sometimes - when you check 2 or 3 books they all have the same mistake - it
> means the authors have been using other books to get some of their
> information.
>
> In the end - the analysis used should be verified with the mine - the
> company that mines g200 spar has a web page for instance - and you can get
> that one and EPK there.
>
> I make sure I have an analysis from the mine or frit maker - or check as
> many sources as possible till I am as certain as I can be.
>
> It is easy to type a wrong number in - check out any data base and you will
> fine errors sooner or later.
>
> And of course make sure you have an LOI and a program that will take it
> into account.
>
> Wish I had the time to check a few data bases - perhaps someone would be
> willing to pay me to check theirs - then we could all get on the same page.
> Forget I said that - who would want a job like that?
>
> RR
>
> >----------------------------Original message----------------------------
> >David Hendley wrote :-
> > If you have a glaze calc program with a good data base of
> >> materials, it is a simple matter to convert any recipe using
> >> American ingredients into a formula. You can then design
> >> a new glaze with the same formula, but with your own
> >> desired ingredients.
> >
> > Unfortunately that does not always work. A friend in the IRC
> >"pottery chat " room gave me the recipe of his "Fairhope Rutile
> >Blue " glaze .
> > Using the known analysis of his raw materials using Insight I
> >recalculated to the current australian raw materials. I also made
> >up a test batch by a straight sub of aussie materials on a %
> >basses . Fired both and scanned the test pieces & sent to him.
> >The recalculated glaze was not correct and the straight % sub
> >looked to him to be very close to his original. Even thought my
> >recalculation was almost a perfect match and the % sub was quite
> >different, go figure !.
> >
> >
> > John Dellow "the flower pot man"
> >Home Page http://www.welcome.to/jkdellow
> >http://digitalfire.com/education/people/dellow/
>
> Ron Roy
> 93 Pegasus Trail
> Scarborough
> Ontario, Canada
> M1G 3N8
> Evenings 416-439-2621
> Fax 416-438-7849
--
John Dellow "the flower pot man"
Home Page http://www.welcome.to/jkdellow
http://digitalfire.com/education/people/dellow/
martin howard on tue 21 mar 00
Ron Roy is right in that there must be bugs somewhere if the recipes,
formulae and analyses of the RMs are not such that we can move from one view
of the glaze to another, seamlessly.
So, three things we could all do, as a group, is
1 notify the discussion list of published errors in RM analyses. The
answer could just be that the author of the book or software had a different
source of the RM from you. So really we might need to have each RM that we
buy analysed separately, if we cannot trust the supplier to provide a
correct one :-((
2 let us all know, and particularly the author of the soft ware know of
any bugs found in older or current versions and the author to then let us
know when they have been corrected and how we can get hold of the up to date
version.
3 Always put the formulae as well as the glaze recipes when posting to
the list, if that is possible. Most of us have a computer program for doing
that, but you, the poster of the glaze, will get more of us to try it out
and show interest if the formula travels with the recipe, as a close
inseparable couple.
Martin Howard
Webb's Cottage Pottery
Woolpits Road
Great Saling
BRAINTREE
Essex CM7 5DZ
01371 850 423
martin@webbscottage.co.uk
www.webbscottage.co.uk Should be ready for 2000 :-) or 2001
Sharon31 on wed 22 mar 00
Hello potters!
Over the last year I tested many glazes.Some of the materials Are not
available or very expensive here.If I would not have access To the formula
many of your glazes would stay in the computer.I must be honest and say that
without ceramic software, I am blind(From the chemistry aspect.)
To John!
My supplier
just started to import Australian Spodumen.Do you have a different analysis
from this one I have in Insight?
.......................SPODUMENE:
CaO 0.12* 0.05%
Li2O 35.59 7.70%
K2O 0.18* 0.12%
Na2O 0.70* 0.31%
TiO2 0.02 0.01%
Al2O3 35.57 26.35%
SiO2149.77 65.38%
Fe2O3 0.06 0.07%
Thanks,
Ababi
sharon@shoval.org.il
http://www.israelceramics.org/main.asp?what=gallery
http://clay.justnet.com/cgallery/asharon.htm
----- Original Message -----
From: John K Dellow
To:
Sent: Tuesday, March 21, 2000 07:57
Subject: Re: Recipes or Formulae
> ----------------------------Original message----------------------------
> To further elaborate on this thread , one needs to keep old
> dated material definitions.
> A problem here in australia for those who were potting in the
> 70's or are using recipes from that period or earlier is the
> closing down of the Broken Hill feldspar mine. A new supply of
> Potash Feldspar was sauced from Western australia which had a
> very different analysis.
> Australian potters can down load 2 of my TMT's for Insight from
> my site at digitalfire ( the URL is at the bottom of this post) .
> I complied 3 ,"pre 80's ,80's & 90's. Some of these analysis came
> from books but most from Data sheets.
> John
> Ron Roy wrote:
> >
> > ----------------------------Original message----------------------------
> > This is to the group John - I'm not saying this is what happened to you.
> >
> > There is a bug in all this - we assume everyones analysis for any
> > particular material is the same or close to ours. Many texts and glazes
> > programs have incorrect analysis for some materials - I could use two
> > glaring examples - one from a book on glazes - with an incorrect frit
> > analysis and a calculation program that was shipped for years with an
> > incorrect analysis for Gerstley Borate.
> >
> > Sometimes - when you check 2 or 3 books they all have the same mistake -
it
> > means the authors have been using other books to get some of their
> > information.
> >
> > In the end - the analysis used should be verified with the mine - the
> > company that mines g200 spar has a web page for instance - and you can
get
> > that one and EPK there.
> >
> > I make sure I have an analysis from the mine or frit maker - or check as
> > many sources as possible till I am as certain as I can be.
> >
> > It is easy to type a wrong number in - check out any data base and you
will
> > fine errors sooner or later.
> >
> > And of course make sure you have an LOI and a program that will take it
> > into account.
> >
> > Wish I had the time to check a few data bases - perhaps someone would be
> > willing to pay me to check theirs - then we could all get on the same
page.
> > Forget I said that - who would want a job like that?
> >
> > RR
> >
> > >----------------------------Original
message----------------------------
> > >David Hendley wrote :-
> > > If you have a glaze calc program with a good data base of
> > >> materials, it is a simple matter to convert any recipe using
> > >> American ingredients into a formula. You can then design
> > >> a new glaze with the same formula, but with your own
> > >> desired ingredients.
> > >
> > > Unfortunately that does not always work. A friend in the IRC
> > >"pottery chat " room gave me the recipe of his "Fairhope Rutile
> > >Blue " glaze .
> > > Using the known analysis of his raw materials using Insight I
> > >recalculated to the current australian raw materials. I also made
> > >up a test batch by a straight sub of aussie materials on a %
> > >basses . Fired both and scanned the test pieces & sent to him.
> > >The recalculated glaze was not correct and the straight % sub
> > >looked to him to be very close to his original. Even thought my
> > >recalculation was almost a perfect match and the % sub was quite
> > >different, go figure !.
> > >
> > >
> > > John Dellow "the flower pot man"
> > >Home Page http://www.welcome.to/jkdellow
> > >http://digitalfire.com/education/people/dellow/
> >
> > Ron Roy
> > 93 Pegasus Trail
> > Scarborough
> > Ontario, Canada
> > M1G 3N8
> > Evenings 416-439-2621
> > Fax 416-438-7849
>
> --
>
> John Dellow "the flower pot man"
> Home Page http://www.welcome.to/jkdellow
> http://digitalfire.com/education/people/dellow/
John K Dellow on thu 23 mar 00
Ababi,
the only Australian analysis I have dates from the 1970's.
It is a little different from the one you have.
SPODUMENE:
CaO 0.008 0.1%
Li2O 0.907 6.8%
MgO 0.013 0.1%
K2O 0.029 0.7%
Na2O 0.030 0.5%
Fe2O3 0.013 0.5%
Al2O3 1.111 28.3%
SiO2 4.181 62.7%
If you go to Lawrence Ewings' Matrix site
http://home.clear.net.nz/pages/Matrix2000/Page2.htm
he has 5 different analysis listed. I don't know how recent they
are though.
John Dellow
Sharon31 wrote:
>
> ----------------------------Original message----------------------------
> Hello potters!
> Over the last year I tested many glazes.Some of the materials Are not
> available or very expensive here.If I would not have access To the formula
> many of your glazes would stay in the computer.I must be honest and say that
> without ceramic software, I am blind(From the chemistry aspect.)
> To John!
> My supplier
> just started to import Australian Spodumen.Do you have a different analysis
> from this one I have in Insight?
> .......................SPODUMENE:
>
> CaO 0.12* 0.05%
> Li2O 35.59 7.70%
> K2O 0.18* 0.12%
> Na2O 0.70* 0.31%
> TiO2 0.02 0.01%
> Al2O3 35.57 26.35%
> SiO2149.77 65.38%
> Fe2O3 0.06 0.07%
> Thanks,
> Ababi
> sharon@shoval.org.il
> http://www.israelceramics.org/main.asp?what=gallery
> http://clay.justnet.com/cgallery/asharon.htm
>
John Dellow "the flower pot man"
Home Page http://www.welcome.to/jkdellow
http://digitalfire.com/education/people/dellow/
ferenc jakab on sat 25 mar 00
The formula for Aus Spod that I have differs from John's only in that Li is
0.9. It's from Matrix V2.
Feri.
Ron Roy on mon 27 mar 00
Excellent point John,
Just to further illustrate the value of both old and new analysis:
Lets say you have a glaze with a material that will no longer be
available or you find a new cheaper or better material that supplies
the oxides you need - lets use Gerstley Borate as an example.
What you need from GB is boron - all other oxides can be
supplemented. If you have the analysis for the version of GB you have
been using it becomes a relatively simple task (relative to your
skill using the molecular formula) to replicate the glaze.
If you have a good picture (molecular wise) of the old glaze your
chances of duplicating it will be very good. In some cases it is
possible to completely change ALL the materials in a glaze and it
will still have ALL the characteristics, look, feel, expansion, flow
etc. of the old one.
In the case of glazes with problems in the bucket you can eliminate
those problems by changing some materials - Neph Sy and GB are two
examples of materials that can cause problems in the bucket and on
the ware.
RR
>----------------------------Original message----------------------------
> To further elaborate on this thread , one needs to keep old
>dated material definitions.
> A problem here in australia for those who were potting in the
>70's or are using recipes from that period or earlier is the
>closing down of the Broken Hill feldspar mine. A new supply of
>Potash Feldspar was sauced from Western australia which had a
>very different analysis.
> Australian potters can down load 2 of my TMT's for Insight from
>my site at digitalfire ( the URL is at the bottom of this post) .
>I complied 3 ,"pre 80's ,80's & 90's. Some of these analysis came
>from books but most from Data sheets.
> John
>Ron Roy wrote:
> >
> > ----------------------------Original message----------------------------
> > This is to the group John - I'm not saying this is what happened to you.
> >
> > There is a bug in all this - we assume everyones analysis for any
> > particular material is the same or close to ours. Many texts and glazes
> > programs have incorrect analysis for some materials - I could use two
> > glaring examples - one from a book on glazes - with an incorrect frit
> > analysis and a calculation program that was shipped for years with an
> > incorrect analysis for Gerstley Borate.
> >
> > Sometimes - when you check 2 or 3 books they all have the same mistake - it
> > means the authors have been using other books to get some of their
> > information.
> >
> > In the end - the analysis used should be verified with the mine - the
> > company that mines g200 spar has a web page for instance - and you can get
> > that one and EPK there.
> >
> > I make sure I have an analysis from the mine or frit maker - or check as
> > many sources as possible till I am as certain as I can be.
> >
> > It is easy to type a wrong number in - check out any data base and you will
> > fine errors sooner or later.
> >
> > And of course make sure you have an LOI and a program that will take it
> > into account.
> >
> > Wish I had the time to check a few data bases - perhaps someone would be
> > willing to pay me to check theirs - then we could all get on the same page.
> > Forget I said that - who would want a job like that?
> >
> > RR
> >
> > >----------------------------Original message----------------------------
> > >David Hendley wrote :-
> > > If you have a glaze calc program with a good data base of
> > >> materials, it is a simple matter to convert any recipe using
> > >> American ingredients into a formula. You can then design
> > >> a new glaze with the same formula, but with your own
> > >> desired ingredients.
> > >
> > > Unfortunately that does not always work. A friend in the IRC
> > >"pottery chat " room gave me the recipe of his "Fairhope Rutile
> > >Blue " glaze .
> > > Using the known analysis of his raw materials using Insight I
> > >recalculated to the current australian raw materials. I also made
> > >up a test batch by a straight sub of aussie materials on a %
> > >basses . Fired both and scanned the test pieces & sent to him.
> > >The recalculated glaze was not correct and the straight % sub
> > >looked to him to be very close to his original. Even thought my
> > >recalculation was almost a perfect match and the % sub was quite
> > >different, go figure !.
> > >
> > >
> > > John Dellow "the flower pot man"
> > >Home Page http://www.welcome.to/jkdellow
> > >http://digitalfire.com/education/people/dellow/
> >
> > Ron Roy
> > 93 Pegasus Trail
> > Scarborough
> > Ontario, Canada
> > M1G 3N8
> > Evenings 416-439-2621
> > Fax 416-438-7849
>
>--
>
> John Dellow "the flower pot man"
>Home Page http://www.welcome.to/jkdellow
>http://digitalfire.com/education/people/dellow/
Ron Roy
93 Pegasus Trail,
Scarborough, Ontario
Canada. M1G 3N8
Tel: 416-439-2621
Fax: 416-438-7849
Ron Roy on mon 27 mar 00
Hi Ababi,
You threw me a curve with this: When I compared the molecular formula
from the analysis I have for Aussi spod it was quite different -
because you had not included Li2O in unity with the fluxes - you
should change your insight unity on fluxes to include it.
When I compare them from the standpoint of % they are close.
If you want the analysis I am using email me (ronroy@total.net) when
I get home in a few days and I will sent it.
RR
>----------------------------Original message----------------------------
>Hello potters!
>Over the last year I tested many glazes.Some of the materials Are not
>available or very expensive here.If I would not have access To the formula
>many of your glazes would stay in the computer.I must be honest and say that
>without ceramic software, I am blind(From the chemistry aspect.)
>To John!
>My supplier
>just started to import Australian Spodumen.Do you have a different analysis
>from this one I have in Insight?
>.......................SPODUMENE:
>
> CaO 0.12* 0.05%
> Li2O 35.59 7.70%
> K2O 0.18* 0.12%
> Na2O 0.70* 0.31%
> TiO2 0.02 0.01%
> Al2O3 35.57 26.35%
> SiO2149.77 65.38%
> Fe2O3 0.06 0.07%
>Thanks,
>Ababi
>sharon@shoval.org.il
>http://www.israelceramics.org/main.asp?what=gallery
>http://clay.justnet.com/cgallery/asharon.htm
>
>----- Original Message -----
>From: John K Dellow
>To:
>Sent: Tuesday, March 21, 2000 07:57
>Subject: Re: Recipes or Formulae
>
>
> > ----------------------------Original message----------------------------
> > To further elaborate on this thread , one needs to keep old
> > dated material definitions.
> > A problem here in australia for those who were potting in the
> > 70's or are using recipes from that period or earlier is the
> > closing down of the Broken Hill feldspar mine. A new supply of
> > Potash Feldspar was sauced from Western australia which had a
> > very different analysis.
> > Australian potters can down load 2 of my TMT's for Insight from
> > my site at digitalfire ( the URL is at the bottom of this post) .
> > I complied 3 ,"pre 80's ,80's & 90's. Some of these analysis came
> > from books but most from Data sheets.
> > John
> > Ron Roy wrote:
> > >
> > > ----------------------------Original message----------------------------
> > > This is to the group John - I'm not saying this is what happened to you.
> > >
> > > There is a bug in all this - we assume everyones analysis for any
> > > particular material is the same or close to ours. Many texts and glazes
> > > programs have incorrect analysis for some materials - I could use two
> > > glaring examples - one from a book on glazes - with an incorrect frit
> > > analysis and a calculation program that was shipped for years with an
> > > incorrect analysis for Gerstley Borate.
> > >
> > > Sometimes - when you check 2 or 3 books they all have the same mistake -
>it
> > > means the authors have been using other books to get some of their
> > > information.
> > >
> > > In the end - the analysis used should be verified with the mine - the
> > > company that mines g200 spar has a web page for instance - and you can
>get
> > > that one and EPK there.
> > >
> > > I make sure I have an analysis from the mine or frit maker - or check as
> > > many sources as possible till I am as certain as I can be.
> > >
> > > It is easy to type a wrong number in - check out any data base and you
>will
> > > fine errors sooner or later.
> > >
> > > And of course make sure you have an LOI and a program that will take it
> > > into account.
> > >
> > > Wish I had the time to check a few data bases - perhaps someone would be
> > > willing to pay me to check theirs - then we could all get on the same
>page.
> > > Forget I said that - who would want a job like that?
> > >
> > > RR
> > >
> > > >----------------------------Original
>message----------------------------
> > > >David Hendley wrote :-
> > > > If you have a glaze calc program with a good data base of
> > > >> materials, it is a simple matter to convert any recipe using
> > > >> American ingredients into a formula. You can then design
> > > >> a new glaze with the same formula, but with your own
> > > >> desired ingredients.
> > > >
> > > > Unfortunately that does not always work. A friend in the IRC
> > > >"pottery chat " room gave me the recipe of his "Fairhope Rutile
> > > >Blue " glaze .
> > > > Using the known analysis of his raw materials using Insight I
> > > >recalculated to the current australian raw materials. I also made
> > > >up a test batch by a straight sub of aussie materials on a %
> > > >basses . Fired both and scanned the test pieces & sent to him.
> > > >The recalculated glaze was not correct and the straight % sub
> > > >looked to him to be very close to his original. Even thought my
> > > >recalculation was almost a perfect match and the % sub was quite
> > > >different, go figure !.
> > > >
> > > >
> > > > John Dellow "the flower pot man"
> > > >Home Page http://www.welcome.to/jkdellow
> > > >http://digitalfire.com/education/people/dellow/
> > >
> > > Ron Roy
> > > 93 Pegasus Trail
> > > Scarborough
> > > Ontario, Canada
> > > M1G 3N8
> > > Evenings 416-439-2621
> > > Fax 416-438-7849
> >
> > --
> >
> > John Dellow "the flower pot man"
> > Home Page http://www.welcome.to/jkdellow
> > http://digitalfire.com/education/people/dellow/
Ron Roy
93 Pegasus Trail,
Scarborough, Ontario
Canada. M1G 3N8
Tel: 416-439-2621
Fax: 416-438-7849
Sharon31 on tue 28 mar 00
Hello Ron!
I chacked, in Insight: Li2O-Part of the RO .Is that what you meant?
The hardest term, for me, to understand, I had to read all the letter,(but I
succeeded at last!) was "Aussi spod"!
Anyway If you meant somthing else, please write to me.
Thanks for paying attention,
Ababi
----- Original Message -----
From: Ron Roy
To:
Sent: Monday, March 27, 2000 10:58
Subject: Re: Recipes or Formulae
> ----------------------------Original message----------------------------
> Hi Ababi,
>
> You threw me a curve with this: When I compared the molecular formula
> from the analysis I have for Aussi spod it was quite different -
> because you had not included Li2O in unity with the fluxes - you
> should change your insight unity on fluxes to include it.
>
> When I compare them from the standpoint of % they are close.
>
> If you want the analysis I am using email me (ronroy@total.net) when
> I get home in a few days and I will sent it.
>
> RR
>
>
>
> >----------------------------Original message----------------------------
> >Hello potters!
> >Over the last year I tested many glazes.Some of the materials Are not
> >available or very expensive here.If I would not have access To the
formula
> >many of your glazes would stay in the computer.I must be honest and say
that
> >without ceramic software, I am blind(From the chemistry aspect.)
> >To John!
> >My supplier
> >just started to import Australian Spodumen.Do you have a different
analysis
> >from this one I have in Insight?
> >.......................SPODUMENE:
> >
> > CaO 0.12* 0.05%
> > Li2O 35.59 7.70%
> > K2O 0.18* 0.12%
> > Na2O 0.70* 0.31%
> > TiO2 0.02 0.01%
> > Al2O3 35.57 26.35%
> > SiO2149.77 65.38%
> > Fe2O3 0.06 0.07%
> >Thanks,
> >Ababi
> >sharon@shoval.org.il
> >http://www.israelceramics.org/main.asp?what=gallery
> >http://clay.justnet.com/cgallery/asharon.htm
> >
> >----- Original Message -----
> >From: John K Dellow
> >To:
> >Sent: Tuesday, March 21, 2000 07:57
> >Subject: Re: Recipes or Formulae
> >
> >
> > > ----------------------------Original
message----------------------------
> > > To further elaborate on this thread , one needs to keep old
> > > dated material definitions.
> > > A problem here in australia for those who were potting in the
> > > 70's or are using recipes from that period or earlier is the
> > > closing down of the Broken Hill feldspar mine. A new supply of
> > > Potash Feldspar was sauced from Western australia which had a
> > > very different analysis.
> > > Australian potters can down load 2 of my TMT's for Insight from
> > > my site at digitalfire ( the URL is at the bottom of this post) .
> > > I complied 3 ,"pre 80's ,80's & 90's. Some of these analysis came
> > > from books but most from Data sheets.
> > > John
> > > Ron Roy wrote:
> > > >
> > > > ----------------------------Original
message----------------------------
> > > > This is to the group John - I'm not saying this is what happened to
you.
> > > >
> > > > There is a bug in all this - we assume everyones analysis for any
> > > > particular material is the same or close to ours. Many texts and
glazes
> > > > programs have incorrect analysis for some materials - I could use
two
> > > > glaring examples - one from a book on glazes - with an incorrect
frit
> > > > analysis and a calculation program that was shipped for years with
an
> > > > incorrect analysis for Gerstley Borate.
> > > >
> > > > Sometimes - when you check 2 or 3 books they all have the same
mistake -
> >it
> > > > means the authors have been using other books to get some of their
> > > > information.
> > > >
> > > > In the end - the analysis used should be verified with the mine -
the
> > > > company that mines g200 spar has a web page for instance - and you
can
> >get
> > > > that one and EPK there.
> > > >
> > > > I make sure I have an analysis from the mine or frit maker - or
check as
> > > > many sources as possible till I am as certain as I can be.
> > > >
> > > > It is easy to type a wrong number in - check out any data base and
you
> >will
> > > > fine errors sooner or later.
> > > >
> > > > And of course make sure you have an LOI and a program that will take
it
> > > > into account.
> > > >
> > > > Wish I had the time to check a few data bases - perhaps someone
would be
> > > > willing to pay me to check theirs - then we could all get on the
same
> >page.
> > > > Forget I said that - who would want a job like that?
> > > >
> > > > RR
> > > >
> > > > >----------------------------Original
> >message----------------------------
> > > > >David Hendley wrote :-
> > > > > If you have a glaze calc program with a good data base of
> > > > >> materials, it is a simple matter to convert any recipe using
> > > > >> American ingredients into a formula. You can then design
> > > > >> a new glaze with the same formula, but with your own
> > > > >> desired ingredients.
> > > > >
> > > > > Unfortunately that does not always work. A friend in the IRC
> > > > >"pottery chat " room gave me the recipe of his "Fairhope Rutile
> > > > >Blue " glaze .
> > > > > Using the known analysis of his raw materials using Insight I
> > > > >recalculated to the current australian raw materials. I also made
> > > > >up a test batch by a straight sub of aussie materials on a %
> > > > >basses . Fired both and scanned the test pieces & sent to him.
> > > > >The recalculated glaze was not correct and the straight % sub
> > > > >looked to him to be very close to his original. Even thought my
> > > > >recalculation was almost a perfect match and the % sub was quite
> > > > >different, go figure !.
> > > > >
> > > > >
> > > > > John Dellow "the flower pot man"
> > > > >Home Page http://www.welcome.to/jkdellow
> > > > >http://digitalfire.com/education/people/dellow/
> > > >
> > > > Ron Roy
> > > > 93 Pegasus Trail
> > > > Scarborough
> > > > Ontario, Canada
> > > > M1G 3N8
> > > > Evenings 416-439-2621
> > > > Fax 416-438-7849
> > >
> > > --
> > >
> > > John Dellow "the flower pot man"
> > > Home Page http://www.welcome.to/jkdellow
> > > http://digitalfire.com/education/people/dellow/
>
> Ron Roy
>
> 93 Pegasus Trail,
> Scarborough, Ontario
> Canada. M1G 3N8
>
> Tel: 416-439-2621
> Fax: 416-438-7849
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