Runyan,Jacob on mon 11 aug 03
Hello All,
Just looking for advice here...
I am about ready to begin glazing a lot of pieces. This is
really my first time being away from a guild/school where
we had glazes that were prepped for us...and honestly, I'm
a little lost...this is where I would like to ask your
advice.
It is my final goal to do my own glaze formulation, as it's
more descriptive of who I am (I work as a chemist). I am
however, unsure as to what to do for now...should I begin
by purchasing glazes from amaco or spectrum and develop my
own glazes along side with a test kiln...or should I just
jump right in and work with glazes from books, etc...then
modify these glazes to what I want. Equipment isn't really
an issue...I have a lot of industrial lab equipment that I
have salvaged. I see it both ways...I want to start making
my own stuff for the experience, but at the same time, I
have good thrown forms...I dont want the clay/throwing time
to go to waste with bad glazes.
Thanks in advance for any advice.
-Jacob
Alisa Clausen on mon 11 aug 03
Dear Jacob.
Because you are a chemist and most probably used to blending chemicals,
etc., I would say you are already well prepared to start mixing your own
tests and glazes. However, I do not know what your expectations are. I
feel from your post that you are anticipating some bad glaze tests, which is
very realistic. Therefore, you want to commit your well thrown work to
glazes that are more reliable, such as premixed. Just for those pots you
have waiting now to be glazed.
I believe that you will find the premixed reliable. In the first glaze
firings, you will be satisfied that the glaze succeeded. However, as you go
along, I believe, that you will find premixed glazes rather shallow in
character. They suit some purposes just fine. A good clear, a consistent
liner glaze, that sort. But as I found, and maybe you will also, that
premixed glazes are like ready to wear clothing. They cover. As you get
more and more into the studio, you will probably like to see some glazes
with many nuances, a little finickey and all together disasters. This way,
you will have to learn more about glaze mixing and chemistry to achieve the
fine tuning or plain surprises that will be exciting and challenging and
therefore more satisfying, then premixed reliability. Like sewing clothing
that really suits your personality, as well as fullfilling the function they
are intended for. In time, you will tweak or mix your recipes to suit your
work and that will give you a sense of reaching your goals. These goals
change endlessly, according to your work, but you will realize goals all the
along the way, which will be highlights and boosts in your journey.
I would say start with the premixed, and in each firing, include tests of
recipes that you mixed yourself. Move along to pots with those recipes that
look promising and go on from those successful pots to bigger batches.
In my opinion, there are dissapointments and disasters in the kiln, but
nothing so terrible to stop you from making new pots and trying it again,
because you like the making pots and are open to the entire process which
includes hammers and keepers.
regards from Alisa in Denmark
Charles Moore on mon 11 aug 03
Hi, Jacob,
Before giving advice on how to start glazing, we need to know what cone
(temperature) you are firing to. Also, are you using an oxidation
kiln(usually electric) or a reduction kiln (usually gas)?
Charles
Sacramento
----- Original Message -----
From: "Runyan,Jacob"
To:
Sent: Monday, August 11, 2003 7:53 AM
Subject: Glazes----Advice
> Hello All,
>
> Just looking for advice here...
>
> I am about ready to begin glazing a lot of pieces. This is
> really my first time being away from a guild/school where
> we had glazes that were prepped for us...and honestly, I'm
> a little lost...this is where I would like to ask your
> advice.
>
> It is my final goal to do my own glaze formulation, as it's
> more descriptive of who I am (I work as a chemist). I am
> however, unsure as to what to do for now...should I begin
> by purchasing glazes from amaco or spectrum and develop my
> own glazes along side with a test kiln...or should I just
> jump right in and work with glazes from books, etc...then
> modify these glazes to what I want. Equipment isn't really
> an issue...I have a lot of industrial lab equipment that I
> have salvaged. I see it both ways...I want to start making
> my own stuff for the experience, but at the same time, I
> have good thrown forms...I dont want the clay/throwing time
> to go to waste with bad glazes.
>
> Thanks in advance for any advice.
>
> -Jacob
>
>
____________________________________________________________________________
__
> 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.
Ababi on mon 11 aug 03
A note from: Ababi Sharon - Glaze addict in Kibbutz Shoval Israel
ababisha@shoval.org.il
http://members4.clubphoto.com/ababi306910
http://www.matrix2000.co.nz/Matrix%20Demo/Ababi.htm
The advantage of being a chemist might help you to know what is under
the surface, not just "these white powder with stange names".
If you choose to mix your own I suggest you to begin with:
One temerature ( cone) in order to learn and be able to learn and to
know what might happens in this cone. Latter you can go widder and use
the conclutions to other cones.
Strat with a simple base and "play around".
See this article of Tony Hansen about his 20/5 recipe. ^6
http://www.digitalfire.ab.ca/cermat/education/114.php?PHPSESSID=c73effad
e108f7dc7856d90c06fd2084
Another glaze I can offer you as a strating point is:
CLEAR (HUDDLESTON)
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
Cone 6 1220 deg.C. -
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
FRIT 3134 50.00
EPK Kaolin 30.00
SILICA 20.00
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
Seger Weight%
KNO 0.318 5.51%
CaO 0.679 10.56%
MgO 0.003 0.03%
Al2O3 0.419 11.85%
P2O5 0.002 0.07%
B2O3 0.627 12.10%
SiO2 3.585 59.76%
TiO2 0.005 0.12%
K2O 0.004 0.10%
Na2O 0.314 5.41%
Al:Si 8.55
Expan. 7.17
ST 324.98
If you are going to use a software the whole world is in your hands!
If not you can try to substitute similar materials and learn what
happens: Instead of frit 3134 try 3110 or 3124. Instead of EPK try
redart or even the soil from your garden!
It is a lovely addiction!
Geoffrey Gaskell on tue 12 aug 03
Jacob Runyan asks if he should:
>jump right in and work with glazes from books, etc...then
>modify these glazes to what I want. Equipment isn't really
>an issue...I have a lot of industrial lab equipment that I
>have salvaged. I see it both ways...I want to start making
>my own stuff for the experience, but at the same time, I
>have good thrown forms...I dont want the clay/throwing time
>to go to waste with bad glazes.
My answer at least is yes. Moreover don't get too attached to any piece that
you have thrown. Disaster can strike at any time. When it does, just make a
new piece.
Being trained in the "scientific method" as you undoubtedly are, you should
be well equipped and used to taking extensive and painstaking notes of every
minute detail, nuance & variation of time, material & conditions of
production. William of Occam's Razor is once again an indispensible tool.
Certain reliable individuals such as Lily Krakowski & Janet Kaiser, I'm
sure, will also be very happy to provide you with a complete list of
proscribed ingredients :-)
Test tiles are standard fare for this sort of thing.
Geoffrey Gaskell
Janice M. Boyd on wed 13 aug 03
Hi Jacob!
I've recently begun preparing my own glazes, and I come from a similar
technical background (biochemistry), so i thought I would share my experience.
For me, all the weighing/calculations/chemical handling is very
straightforward. With a good balance and appropriate precautions, it's
pretty easy.
Now the parts I found hard:
1. Ingredient substitution. I had recipes calling for Gerstley Borate and
albany slip -- both no longer available. And no matter the vendor tells
you, the substitutes are not exactly the same! I've learned to check my
recipes and use ones that call for readily obtainable ingredients.
2. Recipe quality and/or compatibility. I'll try anything - once. Some of
the recipes out there (in my hands) made gorgeous glazes and some made dogs.
SOme glazes work well with one type of clay body and are disastrous on
another. And some glazes are beautiful, but not sturdy.
3. Prepping the slurry/suspension. Going from powder to nicely suspended
glaze was a challenge that I hadn't anticipated when I first began to prep
glazes. SInce nothing in glaze chemistry actually dissolves in water, you
can end up with lumpy, bumpy, gloopy messes. Things turn into unusable
puddings or settle in the bottom of the bucket, never to be resuspended
again. And I've yet to find a glaze recipe that discusses the appropriate
amount of water needed. It is done by guess and by golly. Of course, once
you've made a glaze up you'll have a good idea how much water to use -- but
the next glaze might behave completely differently.
Sooooooo ... here's two cents on what has helped me. Start out with a
couple commercially available powdered glazes -- so you can practice
prepping/sieving/water estimation. When you are comfortable with that, start
testing out recipes. If a piece is lovely and precious test the glaze on
something else first. I usually try out new glazes on a small bowl. If you
are making lots of glazes or doing lots of tests, test tiles are crucial.
And they are easier to store, so you can go back and review your results.
Good luck and happy glazing!
>
>I am about ready to begin glazing a lot of pieces. This is
>really my first time being away from a guild/school where
>we had glazes that were prepped for us...and honestly, I'm
>a little lost...this is where I would like to ask your
>advice.
>
>..should I begin
>by purchasing glazes from amaco or spectrum and develop my
>own glazes along side with a test kiln...or should I just
>jump right in and work with glazes from books, etc...then
>modify these glazes to what I want.
.I dont want the clay/throwing time
>to go to waste with bad glazes.
>
>Thanks in advance for any advice.
>
>-Jacob
>
>______________________________________________________________________________
>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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