Lezlie Finet on tue 30 aug 05
A question about glaze mixing=85
I=92ve been reading about the solubility issues associated with some
commonly used glaze ingredients (such as Gerstley Borate, Neph Sy and
Lithium Carb) that causes some glazes to deteriorate over time.
My own experience seems to prove this out as well, especially with a
couple of my favorite raku glazes.
Thus the idea of fresh-mixing my glazes makes sense, or more practically,
weighing out larger batches of the dry ingredients, and mixing small
amounts with water as needed.
My question is: how do you combine your ingredients so they are THOROUGHLY
distributed, especially in recipes which call for small %s of oxides or
additives. How can I be assured the chemicals are TOTALLY blended? (other
than stirring & whisking & shaking & whipping the heck out of the poor
mess for an excessive amount of time).
I=92m trying not to be too anal about it, but the goal IS consistent
results, right?
How do y=92all do it?
Thanks muchly,
Lezlie in Spokane, WA
Michael Wendt on tue 30 aug 05
Lezlie,
The easy way is to get a cheap cement mixer that has never been used and
blend in it. The even tip down to allow dumping. No need to add the coloring
oxides to the base recipe.
Cover the mouth with an elastic edged sheet of vinyl to reduce dust.
Blend for various times and keep track of the times. If a shorter time
produces spotty results, use the next longer time that gives uniform
mixtures in the tests.
Regards,
Michael Wendt
Wendt Pottery
2729 Clearwater Ave
Lewiston, Idaho 83501
USA
wendtpot@lewiston.com
www.wendtpottery.com
Lezlie asked:
My question is: how do you combine your ingredients so they are THOROUGHLY
distributed, especially in recipes which call for small %s of oxides or
additives. How can I be assured the chemicals are TOTALLY blended? (other
than stirring & whisking & shaking & whipping the heck out of the poor
mess for an excessive amount of time).
I'm trying not to be too anal about it, but the goal IS consistent
results, right?
How do y'all do it?
Thanks muchly,
Lezlie in Spokane, WA
Noel on tue 30 aug 05
>My question is: how do you combine your ingredients so they are THOROUGHLY
>distributed, especially in recipes which call for small %s of oxides or
>additives. How can I be assured the chemicals are TOTALLY blended? (other
>than stirring & whisking & shaking & whipping the heck out of the poor
>mess for an excessive amount of time).
At Brian Gartside's workshop he suggested dry mixing a large batch of base
glaze and then shaking it very well in a plastic garbage bag and storing it
until needed.
Just a thought.
Noel Gilliam
Hickory Flat, Georgia
Charter Member Potters Council
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Paul Lewing on tue 30 aug 05
on 8/30/05 9:33 AM, Lezlie Finet at LaFrog99@YAHOO.COM wrote:
> how do you combine your ingredients so they are THOROUGHLY
> distributed
I have a friend who dry mixes large quantities of materials by putting them
in a drum with a lid that seals tightly. He puts a board in the barrel that
just fits in diagonally, seals it up, and rolls the barrel up and down the
hall for a while.
Paul Lewing, Seattle
Tom at Hutchtel.net on tue 30 aug 05
Everything I've ever read says you cannot do a thorough job of mixing dry
ingredients without high energy mixers like many clay manufacturers have.
The only way is to at least put a wet mix through a screen twice.
Ron, any opinion on this?
Tom Wirt
Hutchinson, MN
twirt@hutchtel.net
www.claycoyote.com
----- Original Message -----
Subject: Re: Dry-mixing Glaze Batches
> >My question is: how do you combine your ingredients so they are
> >THOROUGHLY
>>distributed, especially in recipes which call for small %s of oxides or
>>additives. How can I be assured the chemicals are TOTALLY blended? (other
>>than stirring & whisking & shaking & whipping the heck out of the poor
>>mess for an excessive amount of time).
>
>
> At Brian Gartside's workshop he suggested dry mixing a large batch of base
> glaze and then shaking it very well in a plastic garbage bag and storing
> it
> until needed.
> Just a thought.
David Hendley on tue 30 aug 05
Unless you are mixing hundreds of pounds of glaze, as Michael Wendt
may well do, a cement mixer is complete overkill for dry-mixing glaze.
I put my ingredients in a container that has a lid, which holds twice as
much as I will be mixing. A 5 gallon pickle bucket is good for 5-6000
grams. I do a little mixing of the dry powders each time a new
ingredient is added. Then the lid is snapped on and the bucket can be
rolled around the yard (good exercise) for a few minutes.
I don't know, it might make sense to put some fist-sized rocks in
the bucket, so you would have a "ball mill" mixing effect, but this
method has always worked for me.
I do it for two reasons:
1. It helps to disperse the soda ash (which can turn into hard
chunks) and bentonite (which clumps badly) if they are not
mixed in with the other ingredients.
2. I use the same base for several colors, so I leave out the coloring
ingredients and add them in when making the smaller batches. This
saves time, not making many small batches of the same recipe.
David Hendley
I don't know nothin' but the blues, cobalt that is.
david@farmpots.com
http://www.farmpots.com
----- Original Message -----
> My question is: how do you combine your ingredients so they are THOROUGHLY
> distributed, especially in recipes which call for small %s of oxides or
> additives. How can I be assured the chemicals are TOTALLY blended? (other
> than stirring & whisking & shaking & whipping the heck out of the poor
> mess for an excessive amount of time).
>
> I'm trying not to be too anal about it, but the goal IS consistent
> results, right?
Craig Martell on wed 31 aug 05
Lezlie was asking:
>A question about glaze mixing=85
Hello Lezlie:
I don't dry mix glazes anymore but I can tell you how I used to do it.
Normally I'd do a 10,000 gram batch which yields about 5 gallons of=20
glaze. I would weigh out all the ingredients and put them in a 5 gallon=20
plastic bucket. I had a lid for the buckets that had a hole in the center=
=20
just large enough for a jiffy mixer shaft to pass thru. I would put the=20
mixer in the bucket, put the lid on tight, attach the half inch drill and=20
dry mix for several minutes. The lid kept the dust down but I'd usually do=
=20
this outside. You can then add the mixed dry stuff to water and do all the=
=20
rest of what you need to do.
Now, for a 10,000 gram batch I add 10,000 milliliters of water to the=20
bucket first. Then, if I'm adding bentonite or macaloid, or vee gum=20
etc, I weigh that out and dump it in the water and blunge with the Jiffy=20
mixer until it's totally mixed. Then, I add the clay, if there is any, and=
=20
blunge that too. Then I add all the rest of the stuff and blunge the whole=
=20
batch and sieve thru a 100 mesh screen at least twice, sometimes thrice,=20
adjust the specific gravity and start glazing.
I ball mill the ash glazes so I don't do any blunging at all with those. I=
=20
just put water in the mill and add all the dry stuff and mill for about an=
=20
hour and that's it.
I haven't seen any difference in the glazes with regard to the finished=20
pieces. From these results I've concluded that dry mixing is not at all=20
necessary, with one exception. If I have a glaze or glazes that I use a=20
lot of I can mix 150 lb batches dry in my stainless steel clay mixer and=20
store them until needed. I just weigh out the right batch size, add to=20
water, and mix, sieve, and..............you know all the rest by now.
regards, Craig Martell Hopewell, Oregon
pottery@GARYRFERGUSON.COM on wed 31 aug 05
I do this quite a bit with my Raku glazes.
My dry mix batch size is small enough to put in a quart freezer bag and then
shake the heck out of it. Then I shake it again before I take any out to
mix with water. I'm sure you could to the same thing with plastic buckets
with lids.
This is a great way to have premixed glazes available without them turning
to concrete in the bottom of the glaze bucket (if they have been mixed with
glaze.
Gary Ferguson
http://www.garyrferguson.com
Clay Artist
Nampa, ID 83687
Just Raku Newsletter http://www.justraku.com
Raku Glazes: http://www.rakuglazes.com
Raku Secrets: http://www.rakusecrets.com
Got Raku? http://www.cafepress.com/gotraku
----- Original Message -----
From: "Lezlie Finet"
To:
Sent: Tuesday, August 30, 2005 10:33 AM
Subject: Dry-mixing Glaze Batches
A question about glaze mixing.
I've been reading about the solubility issues associated with some
commonly used glaze ingredients (such as Gerstley Borate, Neph Sy and
Lithium Carb) that causes some glazes to deteriorate over time.
Ron Roy on wed 31 aug 05
Hi Tom,
In school the explanation for sieving was - to get the lumps out and mix it
well.
I have never mixed glazes materials well before adding water for instance -
the sieving did that part very well.
Mixing dry clay is different - the batch must be well mixed before the
water is added in the situation where just enough water is added for
plasticity.
In a liquid mix system the stirring must do the mixing.
One of the main problems in clay mixing is the tendency for some materials
to ball up - that must be avoided at all costs - and premixing is certainly
the answer in that respect.
Not that I'm an expert in this area by the way - I just have some
experience problem solving when things go wrong.
RR
>Everything I've ever read says you cannot do a thorough job of mixing dry
>ingredients without high energy mixers like many clay manufacturers have.
>The only way is to at least put a wet mix through a screen twice.
>
>Ron, any opinion on this?
>
>Tom Wirt
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
John Kudlacek on thu 1 sep 05
Leslie,
Still one more suggestion for dry mixing glazes....small amounts.
I put the glaze ingredients in a Quaker Oats oatmeal box. I put a few
fired porcelain marbles with the materials, in essence making a small ball
mill. Then, of course, snap on the lid and shake.
John Kudlacek
Lezlie Finet on thu 1 sep 05
Thanks to all who responded to my query for methods of dry-mixing glazes.
It=92s interesting to realize how many ways a question can be interpreted! I=
guess I wasn=92t very clear.
Thank you, David (who saw my 'the Birds & the Beads' pieces in Mendocino
so knows the scale I'm working on), for translating my real intentions.
Michael, I too had to chuckle at your cement mixer suggestion - the amount
of glaze you & Barb spill on the floor would probably equal one of my
usual-sized batches (not that you=92re that sloppy!)
And Craig, a 150 lb. batch would last=85 well, let=92s just say I don=92t ha=
ve
THAT many years left.
See, I love to test different glaze combinations and I do lots of multiple-
layering experiments. I use quite an array of glazes, but some
infrequently, thus the need to keep the more soluble ones from
deteriorating over time. I=92m doing mostly raku these days - brushing &
trailing, not dipping or spraying - so large quantities of glaze are not
necessary.
I think the rolling bucket and the shake-n-bake bag suggestions will be
the most efficient way to go for my purposes=85 I=92ll let y=92all know if n=
ot.
Thanks again, Lezlie
in Washington... the REAL one.
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