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ball milling

updated thu 6 dec 01

 

Diane Woloshyn on mon 14 dec 98

What does everyone use inside their ball mills to grind the ingredients?
Hamers says pebbles or stones. Am concerned that the glaze does not become
contaminated with same chips or grindings from the pebbles or stones. How
about small ball bearings or glass marbles? Any help would be appreciated.

Diane Florida Bird Lady

Louis Katz on mon 14 dec 98

Hi Diane
River Worn flint pebbles from France are traditional. They are hard and the
small amount of silica that they add to a glaze could be calculated and
compensated for.
I have always used a slightly overfired porcelain recipe. Although I have
often used it unwedged I would suggest wedging it to remove air bubbles and
help the pebbles wear better.
For turning glass into cullet or dark materials steel shot are available. Also
commercial fused alumina media can be purchased.
It is critical that you have enough grinding medial in the ball mill . If you
have too little the balls travel up the side of the mill and slip down the
side of the mill wearing the mill. When you have enough media the balls travel
up and tumble dow the other side.
There is really good information on this in Pioneed Pottery by Cardew.


Diane Woloshyn wrote:

> ----------------------------Original message----------------------------
> What does everyone use inside their ball mills to grind the ingredients?
>

--
Louis Katz
lkatz@falcon.tamucc.edu
NCECA Director At Large
Texas A&M-CC Division of Visual and Performing Arts Webmaster (512) 994-5987

Dan / Joanne Taylor on tue 15 dec 98

You need grinding media in a ball-mill that has some "tooth", like pebbles of
porcelain. Glass or steel is too smooth. I use high fire, very dense
porcelain balls of various sizes. Industry says you should fill your mill jar
half full of balls, half of which (by weight) are the largest, and two other
sizes 50/50. I'm not sure what ratio I use and I don't think you have to be
that specific but it is most efficient if all the balls are not the same
size. You can make your own. They will wear down in time but the amount that
is left in your glaze is so miniscule as not to matter. Hope this helps.

Dan Taylor in Medicine Hat, Alberta


> What does everyone use inside their ball mills to grind the ingredients?
> Hamers says pebbles or stones. Am concerned that the glaze does not become
> contaminated with same chips or grindings from the pebbles or stones. How
> about small ball bearings or glass marbles? Any help would be appreciated.
>
> Diane Florida Bird Lady

Leon Popik on tue 15 dec 98

I have always used balls that I have rolled out of porcelain. Try to use
different sizes and fire them to cone 10.

Grimmer on tue 15 dec 98

Diane,
You can extrude 'balls' for your mill from a nice, tight porcelain body.
Use a round die about 3/8" in diameter. Cut the long coils into cylinders
about 3/8" long, fire to maturity in a pile on a shelf or in a bowl, and
then run them in your mill by themselves for 12 hours or so to knock off any
rough points. Now you are in business.
steve grimmer
marion illinois

----------
>From: Diane Woloshyn
>To: CLAYART@LSV.UKY.EDU
>Subject: Ball Milling
>Date: Mon, Dec 14, 1998, 8:02 AM
>

>----------------------------Original message----------------------------
>What does everyone use inside their ball mills to grind the ingredients?
>Hamers says pebbles or stones. Am concerned that the glaze does not become
>contaminated with same chips or grindings from the pebbles or stones. How
>about small ball bearings or glass marbles? Any help would be appreciated.
>
>Diane Florida Bird Lady

Frank Gaydos on tue 15 dec 98

Diane,
I'm still using the original porcelain 'balls' that came with my jar. It was
interesting to see the fingerprints of the maker in Japan on them prior to
the first tumble. They are getting smaller and smaller and I guess I will
just re-roll some more balls from porcelain when needed.

-----Original Message-----
Subject: Ball Milling

>What does everyone use inside their ball mills to grind the ingredients?

John K. Dellow on tue 15 dec 98



Diane ,you would do well to get a copy of either Michael Cardew's "Pioneer
Pottery" or Harry Davis's " The Potters Alternative" . They give detailed
information about the type, size of grinding media for ball milling.
John dellow the flower pot man :-)
http://welcome.to/jkdellow

tgschs10 on sun 7 nov 99

I'm getting more and more interested in terra sig decoration and I have been
thru the old correspondences on the subject. An item that I didn't see
discussed and haven't seen in print is making or refining terra sig using a
ball mill.

My questions are the following:
1. Can most clays be used to produce terra sig if extensivley ball milled? I
realize that some clays might lend themselves to terra sig more than others.
For those of us with access to a ball mill, it would seem to be an easier
way to produce modest amounts without all of the waste involved in making it
the conventional way.
2. If one were to use alberta slip, barnards, goldart or redart for
production of a terra sig by ball milling, how long would you recommed they
be tumbled and should the product be further separated manually?
3. This one might be for Vince Pitelka. Can one produce "super-refined terra
sig" by taking a conventional terra sig and ball milling it or just taking a
clay body and ball milling it for several hours or a day or two?
4. If stains are used with terra sig, will the product be improved with ball
milling?

An extra question not related to ball milling. I noticed that some
clayarters recommend sanding the surface in preparation of the surface, at
the workshop I recently attended in N.C. I took a raku clay decorated with
"my first terra sig". I knew they were going to smoke fire the pieces and I
wanted to avoid the breakage from rapid heating and cooling [I was correct -
some attendees lost pieces from breakage]. The raku clay body contained grog
that came to the surface and resulted in some scratching. In part I solved
this problem by applying several coats and had no flaking. Have others used
a raku body?

Vince Pitelka on mon 8 nov 99

Dear tgschs10,
Please sign your posts. It's much nicer responding to a name. I'll try to
answer your questions.

>My questions are the following:
>1. Can most clays be used to produce terra sig if extensivley ball milled? I
>realize that some clays might lend themselves to terra sig more than others.

You can usually get some fraction of terra sig out of almost any clay, but
normally you get the highest yield out of those which tend to be fine
particle-size, and those which have been air-floated, like redart and most
ball clays. A ball mill will be of enormous benefit in making terra sigs
out of other claybodies, especially very coarse ones like barnard slip that
usually tend to settle out completely.

>For those of us with access to a ball mill, it would seem to be an easier
>way to produce modest amounts without all of the waste involved in making it
>the conventional way.

I agree. You should be able to mix up a creamy slip, with deflocculant
added, ball mill it overnight, thin it to the desired consistency. If it
were me, I would still thin it to 1.2 specific gravity, let it settle
overnight, and pour or siphon off the sig, leaving any residue behind in the
bottom. With enough ball milling, there should be very little residue.

>2. If one were to use alberta slip, barnards, goldart or redart for
>production of a terra sig by ball milling, how long would you recommed they
>be tumbled and should the product be further separated manually?

This will have to be trial and error. We did some experimentation with
ball-milling terra sigs at University of Massachusetts when I was a grad
student there fifteen years ago, but I have not had access to a ball mill
until we bought one here a few months ago. I am looking forward to using it
for lots of terra sig experimentation.

>3. This one might be for Vince Pitelka. Can one produce "super-refined terra
>sig" by taking a conventional terra sig and ball milling it or just taking a
>clay body and ball milling it for several hours or a day or two?

Makes sense to me. Again, you will need to run tests. And the performance
of my terra sig recipe has as much to do with thinning it adequately (1.15
S.G.) and applying it in repeated thin coats, as it does with settling and
siphoning.

>4. If stains are used with terra sig, will the product be improved with ball
>milling?

Yes, drastically. Run tests, and let us know how it turns out.

>An extra question not related to ball milling. I noticed that some
>clayarters recommend sanding the surface in preparation of the surface, at
>the workshop I recently attended in N.C. I took a raku clay decorated with
>"my first terra sig". I knew they were going to smoke fire the pieces and I
>wanted to avoid the breakage from rapid heating and cooling [I was correct -
>some attendees lost pieces from breakage]. The raku clay body contained grog
>that came to the surface and resulted in some scratching. In part I solved
>this problem by applying several coats and had no flaking. Have others used
>a raku body?

In my ancient clay workshops and my intro classes I use a raku/sculpture
body exclusively for bonfired terra sig work. The recipe is equal parts
goldart, ball clay, fire clay, and extra fine grog. It sands beautifully,
and with enough coats of terra sig you can get a very glassy finish with no
grog bumps. As long as the terra sig is thinned adequately (1.15 S.G.) you
should have no problems with chipping or flaking.

Good luck -
- Vince

Vince Pitelka
Home - vpitelka@DeKalb.net
615/597-5376
Work - wpitelka@tntech.edu
615/597-6801 ext. 111, fax 615/597-6803
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166

iandol on tue 4 dec 01


Dear Des & Jan Howard,

You say <>

I thought potters were masters of ingenuity and not averse to making =
their own equipment.

Best regards,

Ivor Lewis. Redhill, SA

Des & Jan Howard on wed 5 dec 01


Ivor
You not wrong there.
However, I would sell a porcelain jar of the same size for about $100.

For years we had a dairy goat herd, made 5 varieties of
cheese, yoghurt, cream, butter, grew all our own vegies,
killed our own meat, share farmed on 40 ac. for the wheat,
which we ground for flour & semolina, baked the bread in a
wood stove, had gas lights, dug & mixed our own clay,
used kick wheels, wood kiln. Matter of fact the only items not
grown were tea, sugar & tobacco, we did plant the tea
& tobacco, that's another story.
But, we bought our boots & petrol.
So, gimme a break on this one, we did pay our dues
Des

iandol wrote:

> Dear Des & Jan Howard,
>
> You say <>
>
> I thought potters were masters of ingenuity and not averse to making their own equipment.

--

Des & Jan Howard
Lue Pottery
LUE NSW 2850
Australia
Ph/Fax 02 6373 6419
http://www.luepottery.hwy.com.au