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glaze mixing ?

updated wed 4 nov 98

 

June Perry on thu 29 oct 98

Dear Barney:

I would suggest that you're glaze test batches be no less that 200 grams. That
is what my teacher Vivika Heino taught. 100 grams leaves a bit too much room
for error and doesn't give you enough material either, if you want to test it
on a small pot and/or have some left over for testing over and under other
glazes.

Regards,
June

Barney Adams on thu 29 oct 98

Hi,
I got my triple beam scale in yesterday and now that I've weighed
every small odd and end in my studio I need to move toward doing this glaze
mixing thing. I'm really looking for suggestions as to how to organize
this. I figure on mixing a base glaze from a recipe first and doing tests.
I have bags of powders that I need to organize. What I'm not sure about
is what size batch should I mix up for a test. obviously I dont want to
mix up 25 lbs of a glaze to test. I was thinking of throwing some small
forms for my test rather than tiles. This would allow me to do the 3 dip
test to see the various thickness of application. Also understand that
my approch to glaze is similar to my throwing. I very seldom have any thing
in mind when I start but go with the flow and adjust what I'm doing based
on what's happened. I pretty much try to stay out of the way of the process
and enjoy the result. I dont hold a lot of importance in reproducing the
effect as much as reproducing the reliability.

Thanks,
Barney

Hank Ray on fri 30 oct 98

Hello Barny

most of the time.. i do 400 gram test - with two cups of water in a
blender....
some times, if i almost know what i am gonna get i do a five thousand gram
test....
some times you have to increase the amount of the test by the % of
ingrediants....
if you have in a glaze recipe that contains 0.4% of an oxide you will need to
increase the amount of grams to get an accurate result ...... you can get
away with a hundred gram test for alot of recipes..... but i suggest the
400....

pete... in oklahoma...

ps ..... about 10,000 grams for a five gallon bucket...


------------------------------------------------------------------------------
---------------

Hi,
I got my triple beam scale in yesterday and now that I've weighed
every small odd and end in my studio I need to move toward doing this glaze
mixing thing. I'm really looking for suggestions as to how to organize
this. I figure on mixing a base glaze from a recipe first and doing tests.
I have bags of powders that I need to organize. What I'm not sure about
is what size batch should I mix up for a test. obviously I dont want to
mix up 25 lbs of a glaze to test. I was thinking of throwing some small
forms for my test rather than tiles. This would allow me to do the 3 dip
test to see the various thickness of application. Also understand that
my approch to glaze is similar to my throwing. I very seldom have any thing
in mind when I start but go with the flow and adjust what I'm doing based
on what's happened. I pretty much try to stay out of the way of the process
and enjoy the result. I dont hold a lot of importance in reproducing the
effect as much as reproducing the reliability.

Thanks,
Barney

lpskeen on fri 30 oct 98

Barney Adams wrote:

>>what size batch should I mix up for a test.

Barney,
Congratulations on getting your scale. I recommend throwing some small
teabowl shaped cups off the hump for testing of glazes. This is good
for 2 reasons: first, you get to practice throwing off the hump.
Second, if you get some glazes you like, you can use the cup or sell it.

For testing purposes I usually mix up 500 or 1000g batches. Most
recipes are presented in percentage by weight format, so the math is
easy, and with that small amount, you won't waste a lot of materials.
To avoid glass in the studio, I use those orange cans that powdered
Gatorade comes in for test glazes. Also, I recommend getting one of the
small talisman sieves. It'll fit inside a cup so you don't have a big
mess to clean up.

Good luck!
--
Lisa Skeen ICQ# 15554910
Living Tree Pottery & Soaps http://www.uncg.edu/~lpskeen
"The hottest places in hell are reserved for those who, in times of
great moral crisis, maintain their neutrality." -- Dante

"The opportunity to be threatened, humiliated and to live in fear of
being
beaten to death is the only 'special right' our culture bestows on
homosexuals." - Diane Carman, Denver Post, October 10, 1998

Joy Holdread on fri 30 oct 98

In a message dated 10/29/98 6:57:46 AM US Mountain Standard Time, barn@mcs.net
writes:

> I got my triple beam scale in yesterday and now that I've weighed
> every small odd and end in my studio I need to move toward doing this glaze
> mixing thing. I'm really looking for suggestions as to how to organize
> this. I figure on mixing a base glaze from a recipe first and doing tests.
> I have bags of powders that I need to organize. What I'm not sure about
> is what size batch should I mix up for a test. Obviously I don't want to
> mix up 25 lbs of a glaze to test. I was thinking of throwing some small
> forms for my test rather than tiles. This would allow me to do the 3 dip
> test to see the various thickness of application.

I mix up 100 gram batches. I close the studio doors & windows to prevent dust
blowing and minuate shifting of the gram scale. Wear a mask & mix on large
scraps of naoghhide sp makes for easy clean up. Thrown forms off the hump
make great test tiles you can check for glaze movement. Thrown ridges show
what the glaze does on breaks. Have fun.
Joy

Sherry Lutz on fri 30 oct 98

Hi Barney,
I generally make up 100 gram batches when I'm testing. They will usually fit
into a 6oz. stryo cup. I buy the cups and lids at Sams Club if you have
those around. With a little care they can be cleaned and reused. I bought a
case of 1000 several years ago and still have enough left for another few
years - and I test quite a bit.
Sherry
-----Original Message-----
From: Barney Adams
To: CLAYART@LSV.UKY.EDU
Date: Thursday, October 29, 1998 7:56 AM
Subject: glaze mixing ?


----------------------------Original message----------------------------
Hi,
I got my triple beam scale in yesterday and now that I've weighed
every small odd and end in my studio I need to move toward doing this glaze
mixing thing. I'm really looking for suggestions as to how to organize
this. I figure on mixing a base glaze from a recipe first and doing tests.
I have bags of powders that I need to organize. What I'm not sure about
is what size batch should I mix up for a test. obviously I dont want to
mix up 25 lbs of a glaze to test. I was thinking of throwing some small
forms for my test rather than tiles. This would allow me to do the 3 dip
test to see the various thickness of application. Also understand that
my approch to glaze is similar to my throwing. I very seldom have any thing
in mind when I start but go with the flow and adjust what I'm doing based
on what's happened. I pretty much try to stay out of the way of the process
and enjoy the result. I dont hold a lot of importance in reproducing the
effect as much as reproducing the reliability.

Thanks,
Barney

Janet H Walker on sun 1 nov 98

...what size batch should I mix up for a test...

100 to 200g is plenty. Store it in a container that will facilitate
dipping your test pieces. e.g. if you make skinny cylindrical test
pieces then yoghurt containers make dandy glaze test holders.

Now, a lot of people throw test pieces or throw big bowls and cut
'em into test pieces. BUT if you hate "wasting" the throwing effort
or if you happen not to throw at all, here's an easy way to make
useful test pieces. Roll out a slab and cut it into 5 x 5 inch
square pieces. On the edge destined to become the bottom, make two
cuts straight in from the edge, maybe up to an inch long. Now
texture the slab on one half -- like scratch it with a comb or press
texture into it or whatever. Then coax the clay into a tube and
pinch it closed (thoroughly) to make a cylinder. The bottom edges
can now be spread out to make a good stable base for the piece to
sit on. The texture lets you see how glaze will pool or break.

...my approch to glaze is similar to my throwing...
...go with the flow and adjust what I'm doing based on what's happened

Since you sound like someone who is not likely to make 5 gallons of
one glaze and use it forever on everything, how about concentrating
on making a good base clear glaze that fits your clay(s) exactly.
Maybe start at Tony Hansen's web site (digitalfire.com). Then you
can tinker with it endlessly with colors and opacifiers. Probably
you'll also end up brushing on washes, slips, handfuls of ash, and
so on, in combo with your trusty glaze that fits. (It might not
still fit after some of these assaults but it will be better than
any other!)

...I need to organize...

When you are making up several recipes in the same session, here's a
tip for reducing overhead effort. Make yourself a table with the
names of all the glaze ingredients you're going to need down the
side and the names of the glazes you're making across the top. Then
fill in the table with the amounts in the appropriate spots in the
table. The table will be "spotty" because not every glaze has all
ingredients nor is every ingredient in each glaze. But, when you
have several glazes and some overlap, it really speeds things up!
Often the whiting, the EPK, and the silica are in everything and
you'll have only one or two frits and spars.

So you put some kind of placeholder under the ingredient row you're
working on and e.g. measure out all the bits of whiting and put them
into the right (labelled) containers. Then clean up the scale, put
the whiting away, and go on to the next row.

Make sense? I laid this idea on John Post one time (hi John) and he
professed surprise at how much difference it made even in his
conveniently laid out usuable glaze room. What would REALLY be nice
would be to have a little feature in the glaze database that just
printed out the sheet for you, once you give it the glazes you want
and the batch sizes you're doing. Ahhh, to dream... (Actually this
would be pretty easy to do in Filemaker Pro I suspect.)

So Barney, this may be more than you wanted to know, or it may be
mixed with lots of stuff you already know, but what the heck. Enjoy
using that scale!

Jan Walker
(Who can get the amount of stuff on the scale right in about two
tries when she's on a roll.)

Jim Cullen on tue 3 nov 98

Barn...
Stop on by sometime and we can talk. I've just started doing some extensive
testing using Ian Currie's Systematic Approach. I glaze recipe, 4 sub recipes,
and 35 tests per tile. I'm also testing it on white stoneware and 2 porcelains
at the same time.

I've been thowing small, 3 finger cups for testing.

I've also just set up my spray area so I've got tests coming out of my ears.

Give me a call. I'm in the studio every night except Thursday and Friday.

Keep Centered
CULLEN
Naperville, Illinois