Paul Bush on sun 20 jun 99
Help please. I've bought all the chemicals, got my gram scale,
collected a bunch of recipes I want to use, but nowhere can I find
information regarding how many grams of chemicals and how much water
equals a particular quantity of mixed glaze.
I've heard to use anywhere from 100 to 400 grams for a test batch, but
what about a typical batch size to nearly fill a 5 gallon bucket. Is
there a constant number of grams and quantity of water that will always
yield a 5 gallon batch, or does it differ from recipe to recipe
(assuming I want dipping or pouring consistency in all cases)? None of
my reference books give this information, nor could I find a thread in
the archives.
Thanks,
Paul Bush
Portland, OR
Bryan on sun 20 jun 99
I use 15-20 lbs per five gallon bucket. I dry mix a batch that uses as many
full bags of glaze raw materials as possible, with in reason
Bryan.
-----Original Message-----
From: Paul Bush
To: CLAYART@LSV.UKY.EDU
Date: Sunday, June 20, 1999 10:16 AM
Subject: Glaze batch sizes
>----------------------------Original message----------------------------
>Help please. I've bought all the chemicals, got my gram scale,
>collected a bunch of recipes I want to use, but nowhere can I find
>information regarding how many grams of chemicals and how much water
>equals a particular quantity of mixed glaze.
>
>I've heard to use anywhere from 100 to 400 grams for a test batch, but
>what about a typical batch size to nearly fill a 5 gallon bucket. Is
>there a constant number of grams and quantity of water that will always
>yield a 5 gallon batch, or does it differ from recipe to recipe
>(assuming I want dipping or pouring consistency in all cases)? None of
>my reference books give this information, nor could I find a thread in
>the archives.
>
>Thanks,
>
>Paul Bush
>Portland, OR
>
Donn Buchfinck on mon 21 jun 99
A good way to look at it is to look at the recipie.
10 thousand grams of a normal cone 10 glaze that has a quantity of clay in it
will fill a 5 gallon bucket.
but say a myolica glaze that has mostly frit in it will only fill 2/3rds of a
5 gallon bucket. with 10 thousand grams
also if the glaze settles real bad, put 2 table spoons of muriatic acid in
the glaze when it is mixed up, and it will settle no more
500 gram batch is a good amount to mix in a blender
you can play with the colorants and it will not affect the mix too much when
you dip the test tile
save all the tests in a bucket, when you are done test that, you might get a
real good scrap glaze
Donn Buchfinck
Chris Schafale on mon 21 jun 99
Hi Paul,
For starters, as a broad generalization, you can plan on about
900-1000 ml (=grams) of water for each 1000 grams of glaze materials.
This will vary somewhat from one glaze to another, and you may want
to start at the lower end and then thin to working consistency.
Don't rely on how the the glaze looks, though -- measure the specific
gravity by weighing a 100 ml sample and dividing the weight by 100 --
some glaze ingredients, like Gerstley Borate most notably, will make
the glaze appear very thick. You'll have to experiment some with
each glaze to find the specific gravity that works best, but
somewhere in the 1.45 - 1.55 range seems to usually work.
I find that a 10,000 gram batch pretty consistently fills a
5-gallon bucket. (But I have also learned to my sorrow that it
really pays to test repeatedly in medium-sized batches, like
2000 grams, before you mix a 10000 gram batch -- the small
batches usually aren't really enough to get a good feel for how the
glaze will work on real pots, and it is really annoying to end up
with 10000 grams of something you can't use.)
Best of luck, and feel free to email me if I can help -- I'm about 2
steps ahead of you in this process.
Chris
> ----------------------------Original message----------------------------
> Help please. I've bought all the chemicals, got my gram scale,
> collected a bunch of recipes I want to use, but nowhere can I find
> information regarding how many grams of chemicals and how much water
> equals a particular quantity of mixed glaze.
>
> I've heard to use anywhere from 100 to 400 grams for a test batch, but
> what about a typical batch size to nearly fill a 5 gallon bucket. Is
> there a constant number of grams and quantity of water that will always
> yield a 5 gallon batch, or does it differ from recipe to recipe
> (assuming I want dipping or pouring consistency in all cases)? None of
> my reference books give this information, nor could I find a thread in
> the archives.
>
> Thanks,
>
> Paul Bush
> Portland, OR
>
>
Light One Candle Pottery
Fuquay-Varina, NC
candle@intrex.net
Andrew Buck on mon 21 jun 99
Paul,
The amount of water and the volume of glaze produced will be a little
different for each glaze recipe. That said, usually a 10,000 gram batch
will fill a five gallon bucket to a usable level and 10,000 grams is a
easy amount, mathematically, to figure, from percentages, how much of each
material to weigh out.
Andy Buck
Raincreek Pottery
Port Orchard, Washington
On Sun, 20 Jun 1999, Paul Bush wrote:
> ----------------------------Original message----------------------------
> Help please. I've bought all the chemicals, got my gram scale,
> collected a bunch of recipes I want to use, but nowhere can I find
> information regarding how many grams of chemicals and how much water
> equals a particular quantity of mixed glaze.
>
> I've heard to use anywhere from 100 to 400 grams for a test batch, but
> what about a typical batch size to nearly fill a 5 gallon bucket. Is
> there a constant number of grams and quantity of water that will always
> yield a 5 gallon batch, or does it differ from recipe to recipe
> (assuming I want dipping or pouring consistency in all cases)? None of
> my reference books give this information, nor could I find a thread in
> the archives.
>
> Thanks,
>
> Paul Bush
> Portland, OR
>
Penny Hosler on mon 21 jun 99
Paul,
I was told, and it's seemed to work out fairly well so far, that a
10,000 grams of material (not counting water)usually works for a 5-gal
bucket of glaze. Whatever your recipe, add 2 zeros on the end of each
of the ingredients. For example, Tony's 5x20 recipe would mean you'd
use 2000 grams of each item rather than 20 grams. It's kind of a "oh
wow, duh" method, but I like it. However, don't dump in enough water
to fill the bucket. Just add water until it's right, sometimes only
getting 4 gals.
If I buy a pre-mixed dry glaze, I get about 4-5 gals from 25 lbs of
mix.
As for consistency, here's the scoop (from Tony Hansen, My Hero) --
"Glazes can require vastly different amounts of water. A high clay
glaze,
for example, will take a lot more water, a high frit one a lot less.
Remember, the goal is to get an even layer on your pot that is stuck
on well and not cracked. Make it the thickness required to make that
happen. I would make it about like buttermilk. Stick your dry finger
in and pull it out and you should have a nice even covering with maybe
one drip. If you can add more water and still get a nice even covering
with one drip then do it. Remember also, if the glaze cracks during
drying you have to reduce its plasticity. That means using some
calcined kaolin for raw. You can make calcined kaolin by bisque firing
some regular kaolin in a planter. Tune the mix of raw and calcined
kaolin to give the compromise between hardness and lack of cracking
that you want."
Penny in Sequim, WA
Penny in Sequim, WA
----- Original Message -----
From: Paul Bush
To:
Sent: Sunday, June 20, 1999 8:15 AM
Subject: Glaze batch sizes
> ----------------------------Original
message----------------------------
> Help please. I've bought all the chemicals, got my gram scale,
> collected a bunch of recipes I want to use, but nowhere can I find
> information regarding how many grams of chemicals and how much water
> equals a particular quantity of mixed glaze.
>
> I've heard to use anywhere from 100 to 400 grams for a test batch,
but
> what about a typical batch size to nearly fill a 5 gallon bucket.
Is
> there a constant number of grams and quantity of water that will
always
> yield a 5 gallon batch, or does it differ from recipe to recipe
> (assuming I want dipping or pouring consistency in all cases)? None
of
> my reference books give this information, nor could I find a thread
in
> the archives.
>
> Thanks,
>
> Paul Bush
> Portland, OR
>
Lois Ruben Aronow on mon 21 jun 99
------------------
I usually do 6000 grams for a 5 gallon bucket. I don't measure my
water. After the dry mix, I put enough in to cover well and let it
sit overnight. (I prefer to err on the side of less for slaking).
Then, I sieve it and I keep adding water as I go until I get the
consistency I like.
Yes, there are guidelines for how much water. But every person is
different and every glaze is different. Keep experimenting and you
will discover what works best for you and your pots.
=3EI've heard to use anywhere from 100 to 400 grams for a test batch, but
=3Ewhat about a typical batch size to nearly fill a 5 gallon bucket. Is
=3Ethere a constant number of grams and quantity of water that will always
=3Eyield a 5 gallon batch, or does it differ from recipe to recipe
=3E(assuming I want dipping or pouring consistency in all cases)? None of
=3Emy reference books give this information, nor could I find a thread in
=3Ethe archives.
=3E
=3EThanks,
=3E
=3EPaul Bush
=3EPortland, OR
David Hendley on mon 21 jun 99
Paul,
most people mix up 10,000 gram batches in 5 gallon buckets.
This is actually not 'nearly full' - it's more like about 3 1/2 to 4
gallons, but that leaves plenty of room for dipping.
It also makes for easy arithmetic since most glaze recipes are stated
in 100 gram batches.
I mix up 15,000 gram batches in 5 gallon buckets if,
1 -- I know it is a good, reliable glaze that I want to use often, and
2 -- I'm mixing up a completely new batch. In other words, I don't
have much left over from the last time I made the glaze.
This still leave enough room in the bucket for dipping small to
medium pots.
Remember that 15,000 grams, or even 10,000 grams, is a LOT of
glaze if you are doing pottery as a hobby and not producing a lot
of work.
David Hendley
Maydelle, Texas
hendley@tyler.net
http://www.farmpots.com
At 11:15 AM 6/20/99 EDT, you wrote:
>----------------------------Original message----------------------------
>Help please. I've bought all the chemicals, got my gram scale,
>collected a bunch of recipes I want to use, but nowhere can I find
>information regarding how many grams of chemicals and how much water
>equals a particular quantity of mixed glaze.
>
>I've heard to use anywhere from 100 to 400 grams for a test batch, but
>what about a typical batch size to nearly fill a 5 gallon bucket. Is
>there a constant number of grams and quantity of water that will always
>yield a 5 gallon batch, or does it differ from recipe to recipe
>(assuming I want dipping or pouring consistency in all cases)? None of
>my reference books give this information, nor could I find a thread in
>the archives.
>
>Thanks,
>
>Paul Bush
>Portland, OR
>
David Hendley
Maydelle, Texas
hendley@tyler.net
http://www.farmpots.com
Laura Speirs on mon 21 jun 99
Dear Paul,
Most of us, I think, start w/l00 gm batches mixed with enough water to get
the consistency you're used to glazing with. Then put it on a bisqued test
tile or little test
bowl and mark the bottom of each tile w/iron oxide mixed in water or an
underglaze with the number of the glaze you're using. If that turns out
well, then mix l000 gms and see what you get.
Do not, under any circumstances, do the dumb thing I did, i.e. mix a 5
gallon bucket (20 lbs of glaze materials) based on a l00 gm test. The
beautiful fleshy pink w/gold stripes glaze I got at l00 gms turned into a
glassy pool on my kiln shelf and was a total loss of glaze materials, time,
and hopes. I learned that lesson but good!
Testing glazes is a tedious, often thankless job, but it has to be done by
all of us since even water in different areas of the country can make a huge
difference in results. Unless you have lots and lots of colorants in your
recipe, 20 lbs usually fills the 5- gallon bucket.
Good luck.
Laura in Oregon
-----Original Message-----
From: Paul Bush
To: CLAYART@LSV.UKY.EDU
Date: Sunday, June 20, 1999 8:16 AM
Subject: Glaze batch sizes
>----------------------------Original message----------------------------
>Help please. I've bought all the chemicals, got my gram scale,
>collected a bunch of recipes I want to use, but nowhere can I find
>information regarding how many grams of chemicals and how much water
>equals a particular quantity of mixed glaze.
>
>I've heard to use anywhere from 100 to 400 grams for a test batch, but
>what about a typical batch size to nearly fill a 5 gallon bucket. Is
>there a constant number of grams and quantity of water that will always
>yield a 5 gallon batch, or does it differ from recipe to recipe
>(assuming I want dipping or pouring consistency in all cases)? None of
>my reference books give this information, nor could I find a thread in
>the archives.
>
>Thanks,
>
>Paul Bush
>Portland, OR
>
William Hewlett on mon 21 jun 99
------------------
I think the easyest way to determine the amount of water for the amount of
dry glaze you have is to gradually add water to the bucket,( ware rubber
gloves and a mask) Slowely add water and mix it up as water is being added
until it is the consistancy of coffee cream. So it really doesn't matter
if you have 100 grams (which I use for a text glaze) or 5,000 grams, mix to
the consistancy of coffee cream. With class room glaze buckets, I tend to
water it down more because beginning students usually put the glaze on too
thick, and it starts to crack off the pots, they have to wash it off and
start over, and that is a waist of glaze. After it is mixed up, I have the
same size bucket, and strain it all through a 60 mesh strainer, and it's
ready to go.
Joyce A
Mission, TX
Herb Moses on mon 21 jun 99
Here is a little of my seat of the pants methodology:
I start with 100 gram batches for most tests. I put it in a tupperware,
seal tightly, and shake to distribute well. I dribble the water in until it
is the consistency I want (heavy cream, or thinner).
For glazes I am more sure of, I use a 1000 gram batch in a small bucket. I
find that if I want to test a known base with a new colorant, 100 grams just
isn't enough to check for color subtleties. Again, I add water to the dry
ingredients.
For mixing 10000 gram batches, I mix the ingredients together, and add them
to the water. For those five gallon buckets, I start with a little less
than half full of water, and that is usually correct.
Good luck.
Herb
http://www.usapottery.com
Palm Springs Pottery
Now Open!
198 S. Indian Canyon Drive
Palm Springs, CA 92262
----- Original Message -----
From: Paul Bush
To:
Sent: Sunday, June 20, 1999 8:15 AM
Subject: Glaze batch sizes
> ----------------------------Original message----------------------------
> Help please. I've bought all the chemicals, got my gram scale,
> collected a bunch of recipes I want to use, but nowhere can I find
> information regarding how many grams of chemicals and how much water
> equals a particular quantity of mixed glaze.
>
> I've heard to use anywhere from 100 to 400 grams for a test batch, but
> what about a typical batch size to nearly fill a 5 gallon bucket. Is
> there a constant number of grams and quantity of water that will always
> yield a 5 gallon batch, or does it differ from recipe to recipe
> (assuming I want dipping or pouring consistency in all cases)? None of
> my reference books give this information, nor could I find a thread in
> the archives.
>
> Thanks,
>
> Paul Bush
> Portland, OR
>
Stephen Mills on mon 21 jun 99
At Bath Potters we work on the basis of 3 kilos (approx. 6.6lbs) of
powdered material to a UK gallon (4.5 litres).
Steve
Bath
UK
I'll bet my partner Mike answers this one as well!
In message , Paul Bush writes
>----------------------------Original message----------------------------
>Help please. I've bought all the chemicals, got my gram scale,
>collected a bunch of recipes I want to use, but nowhere can I find
>information regarding how many grams of chemicals and how much water
>equals a particular quantity of mixed glaze.
>
>I've heard to use anywhere from 100 to 400 grams for a test batch, but
>what about a typical batch size to nearly fill a 5 gallon bucket. Is
>there a constant number of grams and quantity of water that will always
>yield a 5 gallon batch, or does it differ from recipe to recipe
>(assuming I want dipping or pouring consistency in all cases)? None of
>my reference books give this information, nor could I find a thread in
>the archives.
>
>Thanks,
>
>Paul Bush
>Portland, OR
>
--
Steve Mills
Bath
UK
home e-mail: stevemills@mudslinger.demon.co.uk
work e-mail: stevemills@bathpotters.demon.co.uk
own website: http://www.mudslinger.demon.co.uk
BPS website: http://www.bathpotters.demon.co.uk
Rick hugel on mon 21 jun 99
To the right of each ingredient is a number which you can take to mean the
percentage of the total amount of glaze you want to mix. For Example:
Feldspar 25
Whiting 25
Ball Clay 25
Flint 25
What ever the numbers are they should add up to 100. Any oxides for
coloring are listed as "ADD". Now say you want to mix a 10 pound batch of
a glaze, you calculate Feldspar's 25 as 25percent of 10 pounds equals 2.5
pounds. Do the same for each ingredient and the oxides. Wearing rubber
gloves, mix the dry ingredients together well, kind of make the whole patch
even across the top and then add water all at one time until it just covers
the dry batch. Let it sit so that the water seeps all through the
materials. After a while the top of the materials may become exposed as
the water soaks in - just add a little more water if that happens. After a
few hours or better yet overnight, all the materials should have absorbed
all the water needs and you should be able to stir it. And it will
probably be rather thick. You now have to pass the entire batch through a
sieve of at least 80 mesh and there may still be some lumps of the
materials in the batch. Using a bathroom brush sieve the batch and any
lumps dump back into the original bucket. If the batch is too thick it
will be hard to sieve so you should add a LITTLE water to thin it out.
After everything is sieved, break up any lumps you may have with a spoon
and a little water and run that through the sieve. You will always have
some residue left over, so figure out where you are going to dump it. Now
test the final batch for thickness. Most glazes are about the consistency
of paint after having been thinned for application. You can also take a
few broken pieces of bisqued ware and test this way. Dip different pieces
into the glaze for different time periods starting with 1 second and
extending to 5 or even more seconds. This is really difficult to set down
to a definit dipping time pattern because each pot and its size and the
combination of glazes used differs with each potter, so you will have to do
a bit of experimenting until you have matched the glaze consistency to the
dipping time. After dipping each piece and letting it dry, make a scratch
in it to see how thick it glaze is. Again, you will have to test fire your
glazes to find out the correct thickness for each glaze. After you have
been mixing glazes for a while, you will not have to do the scratching test
anymore unless it is a new glaze you are mixing for the first time. And
yes, different ingredients will require more or less water to reach the
same consitency. Hope this helps. Go to it!
Rick
>----------------------------Original message----------------------------
>I use 15-20 lbs per five gallon bucket. I dry mix a batch that uses as many
>full bags of glaze raw materials as possible, with in reason
>Bryan.
>-----Original Message-----
>From: Paul Bush
>To: CLAYART@LSV.UKY.EDU
>Date: Sunday, June 20, 1999 10:16 AM
>Subject: Glaze batch sizes
>
>
>>----------------------------Original message----------------------------
>>Help please. I've bought all the chemicals, got my gram scale,
>>collected a bunch of recipes I want to use, but nowhere can I find
>>information regarding how many grams of chemicals and how much water
>>equals a particular quantity of mixed glaze.
>>
>>I've heard to use anywhere from 100 to 400 grams for a test batch, but
>>what about a typical batch size to nearly fill a 5 gallon bucket. Is
>>there a constant number of grams and quantity of water that will always
>>yield a 5 gallon batch, or does it differ from recipe to recipe
>>(assuming I want dipping or pouring consistency in all cases)? None of
>>my reference books give this information, nor could I find a thread in
>>the archives.
>>
>>Thanks,
>>
>>Paul Bush
>>Portland, OR
>>
Mike Bailey on tue 22 jun 99
In message , Paul Bush writes
>----------------------------Original message----------------------------
>Help please. I've bought all the chemicals, got my gram scale,
>collected a bunch of recipes I want to use, but nowhere can I find
>information regarding how many grams of chemicals and how much water
>equals a particular quantity of mixed glaze.
>
>I've heard to use anywhere from 100 to 400 grams for a test batch, but
>what about a typical batch size to nearly fill a 5 gallon bucket. Is
>there a constant number of grams and quantity of water that will always
>yield a 5 gallon batch, or does it differ from recipe to recipe
>(assuming I want dipping or pouring consistency in all cases)? None of
>my reference books give this information, nor could I find a thread in
>the archives.
>
>
Dear Paul.
The main variable that determines the water:powder ratio is usually the
amount of clay in the recipe. To take the extremes.
100 gms of a glaze without any clay in the recipe might need as little
as 80 gms of water to get a normal stoneware dipping glaze.
100 gms of a high ball clay glaze / engobe might need 200 gms of water.
Most glazes, though, need for 100 gms of glaze between 100 and 120 gms
of water.
from this you can see that a kilo of glaze typically needs around 1
litre of water which gives about 1.5 litres of slop glaze.
If we are mixing our units (my old physics teacher would have a fit!)
3kgs of dry glaze powder makes about a gallon of slop glaze.
Hope this helps,
Best wishes.
Mike
--
Mike Bailey. Bath. U.k.
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