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spraying ash glazes and sieving frits

updated sat 24 feb 01


Cindy Strnad on wed 21 feb 01

Hello, Jeff.

I think the answer to your frit question is the same as the answer to your
ash question. You need a coarser sieve. I like 80 mesh, but I have
successfully sieved frits through much finer mesh. What frit are you using?
I've sieved 3134, 3124, 3110, and a couple of others I can't remember
off-hand with no difficulty.

I wonder if it may be some other glaze ingredient that's actually causing
the trouble. Wollastonite and Whiting are always a little difficult for me,
though they eventually go through with minimal residue.

As for suspending frits, all my frit recipes are high in clay content, so I
haven't had any trouble with this. If you have low clay content, you may
want to add some bentonite. Try one or two percent, and mix it up in a
blender with water before hand. I've also successfully mixed it by adding
water to the dry powder, stirring as I do. I treat it like corn starch.

As always, wear your mask. Hope this helps,

Cindy Strnad
Earthen Vessels Pottery
RR 1, Box 51
Custer, SD 57730

Jeff van den Broeck on wed 21 feb 01

Many thanks to all of you who have been so nice and quick to reply to my
question about spraying ash glazes.
I am aware that the second question in my message has been overlooked.
Perhaps my fault.
My first question was how to sieve the ash glaze. Yes Phil, I should have
known. Sorry.
My second question didn't get attention: how to pass frits through the
sieve? I always tried to avoid frits because they are so difficult to pass
through the sieve and they settle so quickly, but perhaps once more I'm not
well informed.
I would appreciate suggestions and solutions. ( I have to repeat that I
don't have a ball-mill.)
Many thanks, Jeff
Jeff van den Broeck
P,O,Box 1099, Baguio City 2600

Lili Krakowski on fri 23 feb 01

Frans Wildenhain used to say that people USED to have to sieve because raw
materials were so "rough" and many had to be mortar-and-pestled before
going into the glaze. Today (and here, somewhere in his book Leach says
same thing) materials are superfine, and unless something special is going
on, (you are using locally dug clay) you do not need to sieve except for
mixing. I sieve all my glazes when newly mixed, using a fiberglass window
screen sieve first (kitchen sieve will do) and and a "painter's sock" [ a
bag shaped a bit like those red flannel stocking they sell for mantle use
at Christmas. Used by painters to sieve paint that goes in a spray gun.]
I make sieves out of them. (NO no the painters! The socks!! Not the
felt ones; the nylon ones from the hardware store!

At teh suggestion of some book (sorry, author; is it you Emmanule Cooper,
or you Harry Fraser?) I let the just mixed glaze
sit and rest and absorb the water at least 24 hours in plenty of water
beforesieving the first time.

I do a fresh sieving every time I use the glaze if it has stood
around for a few days. I also sieve any glazes that are classroom glazes,
as students do not always remove all dust from their pots, and they drop
things into the bucket.

Lili Krakowski