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glaze calculation th 5x20

updated wed 3 oct 01

 

Cindy Strnad on sat 29 sep 01


Dear Nikki,

You are making it harder than it needs to be. EPK
works just fine--it's what I use in Tony H's 5x20,
anyway. If you're having trouble with a clear
glaze not being as clear as you like, you might
want purer/cleaner materials, but Tony H. has a
special recipe for clear anyway. Just use the EPK.
If you don't like the results, you can try
something pricier.

Cindy Strnad
Earthen Vessels Pottery
RR 1, Box 51
Custer, SD 57730
USA
cindy@earthen-vessels-pottery.com
http://www.earthen-vessels-pottery.com

Nikki Simmons on sat 29 sep 01


Hello Clayart,

Oh boy Oh boy, am I getting confused. I have been getting glaze tests ready
for the past several weeks/months (I have a small child so I do it as I have
time), and now I am trying to figure out how to use Insight. I would
appreciate some help. I have several questions coming. Here's the first
question.

I want to try Tony's 5x20 Clear Glaze. (For those that are new see:
http://digitalfire.com/education/glaze/cone6.htm )

Base Transparent Glossy 5x20
FRIT 3134 20
PIONEER KAOLIN 20
SILICA 20
CUSTER FELDSPAR 20
WOLLASTONITE 20

At one point he mentions replacing EPK Kaolin with Pioneer Kaolin, a cleaner
kaolin. So I talked to my supplier (L&R Specialties in Nixa Missouri), and
they only carry and suggested Diamond. So I brought some home.

My question is: can someone help me compare the analysis of Pioneer versus
EPK versus Diamond. I would prefer to use EPK because it is cheap and I
always have on hand for other glazes. This is an instance of where I am not
sure how to evaluate if it will benefit me to buy the Diamond or just stick
with EPK. I should mention that L&R could not supply me with an analysis
sheet, so I am going with the numbers I am finding in Insight.

Sincerely,
Nikki Simmons
nsimmons@mid-mo.net

Ababi on sat 29 sep 01


You don't have to take it too seriously.
As a "Glaze addict" I have many materials. When I made the 20/5 I used
20 Norwegian potash feldspar with only estimated analyses. I use this
feldspar regularly. Only for special cases I use Custer feldspar.
I used 20 English Kaolin CC31
I used 20 Quartz
20 Wolastonite
20 Frit 3134
It turned good. I think you go too far.
You tell me: Ababi , you convinced me to buy a program. I spent the money,
and now I am stuck!
Tony Hansen allowed me to copy from his book so here is:
DIAMOND KAOLIN
Description: SECONDARY INTERMEDIATE PSD
Date: 09/05/97
Supplier: K&T CLAYS
Raw Weight: 267.92
Family: 2-Kaolin
ANALYSIS & UNITY FORMULA
CaO....... 0.15% 0.01
K2O....... 0.18% 0.01
MgO....... 0.10% 0.01
Na2O...... 0.08% 0.00
TiO2...... 1.40% 0.05
Al2O3..... 37.90% [ 1.00]
SiO2...... 45.60% 2.04
Fe2O3..... 0.70% 0.01
LOI....... 13.50%
Tony Hansen writes that the manufacturer claims this material is a
substitute for
GK Pioneer Kaolin.

Now
PIONEER KAOLIN
Description: GENERAL PURPOSE KAOLIN
ANALYSIS & UNITY FORMULA
CaO....... 0.24% 0.01
MgO....... 0.14% 0.01
Na2O...... 0.04% 0.00
Na2O...... 0.14% 0.01
TiO2...... 1.43% 0.05
Al2O3..... 38.51% [ 1.00]
SiO2...... 45.68% 2.01
Fe2O3..... 0.44% 0.01
LOI....... 13.92%

OK. Give it sometime, you will learn, with the time these annoying numbers
will get meaning, might be like a poem- that how I feel about them.
I give you here a recipe. You try to convert it and use with your materials,
you might not succeed, but you will learn.
First insert this frit

FRIT 6004


K2O 0.47* 15.50%
Na2O 0.53* 11.50%
Al2O3 0.10 3.50%
B2O3 1.05 25.50%
SiO2 2.09 44.00%

Now try to convert this recipe to your materials. You might not succeed to
do it exactly, but let us see:
Untitled Recipe
=================
SILICA.............. 36.5 36.53%
FRIT 6004........... 15.7 15.75%
ENGLISH KAOLIN CC31. 26.1 26.07%
WHITING............. 21.7 21.66%
========
100.0

CaO 0.77* 13.91%
K2O 0.12* 3.69%
Na2O 0.10* 2.07%
TiO2 0.00 0.03%
Al2O3 0.35 11.28%
B2O3 0.21 4.60%
SiO2 3.33 64.20%
Fe2O3 0.00 0.24%
text "1000"
Si:Al 9.66
SiB:Al 10.26
Expan 7.21

As the time passes whenever you will get a new recipe you will look for
these numbers:
According to my firing:
CaO 0.77* 13.91%
K2O 0.12* 3.69% ...Do I have enough flux?
Na2O 0.10* 2.07%
TiO2 0.00 0.03%
Al2O3 0.35 11.28% ....What about alumina
B2O3 0.21 4.60%
SiO2 3.33 64.20%
Fe2O3 0.00 0.24%

text "1000"$ ..........too expensive!!!!
Si:Al 9.66
SiB:Al 10.26 ...this is fine!
Expan 7.21 ....not enough expansive?
Great fun, better than TV
Ababi Sharon
ababisharon@hotmail.com
http://members4.clubphoto.com/ababi306910/
http://www.milkywayceramics.com/cgallery/asharon.htm
http://www.israelceramics.org/



----- Original Message -----
From: "Nikki Simmons"
To:
Sent: Saturday, September 29, 2001 05:35
Subject: Glaze Calculation TH 5x20


> Hello Clayart,
>
> Oh boy Oh boy, am I getting confused. I have been getting glaze tests
ready
> for the past several weeks/months (I have a small child so I do it as I
have
> time), and now I am trying to figure out how to use Insight. I would
> appreciate some help. I have several questions coming. Here's the first
> question.
>
> I want to try Tony's 5x20 Clear Glaze. (For those that are new see:
> http://digitalfire.com/education/glaze/cone6.htm )
>
> Base Transparent Glossy 5x20
> FRIT 3134 20
> PIONEER KAOLIN 20
> SILICA 20
> CUSTER FELDSPAR 20
> WOLLASTONITE 20
>
> At one point he mentions replacing EPK Kaolin with Pioneer Kaolin, a
cleaner
> kaolin. So I talked to my supplier (L&R Specialties in Nixa Missouri),
and
> they only carry and suggested Diamond. So I brought some home.
>
> My question is: can someone help me compare the analysis of Pioneer versus
> EPK versus Diamond. I would prefer to use EPK because it is cheap and I
> always have on hand for other glazes. This is an instance of where I am
not
> sure how to evaluate if it will benefit me to buy the Diamond or just
stick
> with EPK. I should mention that L&R could not supply me with an analysis
> sheet, so I am going with the numbers I am finding in Insight.
>
> Sincerely,
> Nikki Simmons
> nsimmons@mid-mo.net
>
>
____________________________________________________________________________
__
> 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.
>

Ron Roy on sun 30 sep 01


Hi Nikki,

This is going to be easy - keep using the EPK - it's the whitest burning
kaolin that we have tested - including pioneer and grolleg.

The kaolins - as a group of claysare very close in their analysis - when
substituting I would suggest one for one.

I also suggest testing that glaze with different kaolins just to see if
there is a difference - I don't think anyone will notice the difference -
certainly not at cone 6 oxidation.

Pioneer is not a plastic kaolin and may tend to encourage crawling.

The 325 m silica we get here in NA is almost the same as the 200M - I have
only use the 200m. I have done some testing with the two and cannot see any
difference at cone 6, 8 or 10.

RR


>Oh boy Oh boy, am I getting confused. I have been getting glaze tests ready
>for the past several weeks/months (I have a small child so I do it as I have
>time), and now I am trying to figure out how to use Insight. I would
>appreciate some help. I have several questions coming. Here's the first
>question.
>
>I want to try Tony's 5x20 Clear Glaze. (For those that are new see:
>http://digitalfire.com/education/glaze/cone6.htm )
>
>Base Transparent Glossy 5x20
>FRIT 3134 20
>PIONEER KAOLIN 20
>SILICA 20
>CUSTER FELDSPAR 20
>WOLLASTONITE 20
>
>At one point he mentions replacing EPK Kaolin with Pioneer Kaolin, a cleaner
>kaolin. So I talked to my supplier (L&R Specialties in Nixa Missouri), and
>they only carry and suggested Diamond. So I brought some home.
>
>My question is: can someone help me compare the analysis of Pioneer versus
>EPK versus Diamond. I would prefer to use EPK because it is cheap and I
>always have on hand for other glazes. This is an instance of where I am not
>sure how to evaluate if it will benefit me to buy the Diamond or just stick
>with EPK. I should mention that L&R could not supply me with an analysis
>sheet, so I am going with the numbers I am finding in Insight.
>
>Sincerely,
>Nikki Simmons
>nsimmons@mid-mo.net

Ron Roy
RR# 4
15084 Little Lake Rd..
Brighton,
Ontario, Canada
KOK 1H0
Residence 613-475-9544
Studio 613-475-3715
Fax 613-475-3513

Paul Lewing on mon 1 oct 01


on 10/1/01 12:33 PM, Valerie Hawkins at vhawkins1@CAROLINA.RR.COM wrote:

> A somewhat related question - is there a difference between 'china clay' and
> 'grolleg'?

Valerie,
"China clay" and "kaolin" are words for the same kind of white high-fire
clay. "Grolleg" is a particular brand of china clay from England, just as
EPK (Edgar Plastic Kaolin, from Edgar, Florida) is a brand of kaolin.
Paul Lewing, Seattle
who had the pleasure of attending an Ian Currie workshop this last weekend
in Tacoma, and the further pleasure of taking him on a hike in Mt. Rainier
National Park on Friday. What a lovely man, and I can hardly wait to make
some of those grid tiles.

Valerie Hawkins on mon 1 oct 01


A somewhat related question - is there a difference between 'china clay' and
'grolleg'?

-----Original Message-----
From: Ceramic Arts Discussion List [mailto:CLAYART@LSV.CERAMICS.ORG]On
Behalf Of Ron Roy
Sent: Sunday, September 30, 2001 7:39 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: Glaze Calculation TH 5x20


Hi Nikki,

This is going to be easy - keep using the EPK - it's the whitest burning
kaolin that we have tested - including pioneer and grolleg.

The kaolins - as a group of claysare very close in their analysis - when
substituting I would suggest one for one.

I also suggest testing that glaze with different kaolins just to see if
there is a difference - I don't think anyone will notice the difference -
certainly not at cone 6 oxidation.

Pioneer is not a plastic kaolin and may tend to encourage crawling.

The 325 m silica we get here in NA is almost the same as the 200M - I have
only use the 200m. I have done some testing with the two and cannot see any
difference at cone 6, 8 or 10.

RR


>Oh boy Oh boy, am I getting confused. I have been getting glaze tests
ready
>for the past several weeks/months (I have a small child so I do it as I
have
>time), and now I am trying to figure out how to use Insight. I would
>appreciate some help. I have several questions coming. Here's the first
>question.
>
>I want to try Tony's 5x20 Clear Glaze. (For those that are new see:
>http://digitalfire.com/education/glaze/cone6.htm )
>
>Base Transparent Glossy 5x20
>FRIT 3134 20
>PIONEER KAOLIN 20
>SILICA 20
>CUSTER FELDSPAR 20
>WOLLASTONITE 20
>
>At one point he mentions replacing EPK Kaolin with Pioneer Kaolin, a
cleaner
>kaolin. So I talked to my supplier (L&R Specialties in Nixa Missouri), and
>they only carry and suggested Diamond. So I brought some home.
>
>My question is: can someone help me compare the analysis of Pioneer versus
>EPK versus Diamond. I would prefer to use EPK because it is cheap and I
>always have on hand for other glazes. This is an instance of where I am
not
>sure how to evaluate if it will benefit me to buy the Diamond or just stick
>with EPK. I should mention that L&R could not supply me with an analysis
>sheet, so I am going with the numbers I am finding in Insight.
>
>Sincerely,
>Nikki Simmons
>nsimmons@mid-mo.net

Ron Roy
RR# 4
15084 Little Lake Rd..
Brighton,
Ontario, Canada
KOK 1H0
Residence 613-475-9544
Studio 613-475-3715
Fax 613-475-3513

____________________________________________________________________________
__
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.

Ron Roy on tue 2 oct 01


Grolleg is a china clay - not much difference chemically between them all -
EPK, Tile 6, Pioneer, Helmer and Grolleg - You would not notice any
difference in a glaze using any of them.

Grolleg has less TiO2 and is therefore prefered for translucent porcelain
bodies.

RR

>A somewhat related question - is there a difference between 'china clay' and
>'grolleg'?


Ron Roy
RR# 4
15084 Little Lake Rd..
Brighton,
Ontario, Canada
KOK 1H0
Residence 613-475-9544
Studio 613-475-3715
Fax 613-475-3513