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forgiving slips

updated fri 24 oct 03

 

mlkrakowski@citlink.net on tue 21 oct 03


I hope this gets through. My server has "improved" the service which
means it has tanked.


Ok. I have found that most slips fit commercially made bodies. I
expect that this is because most of them shrink around 12% and the
slips can deal with that.

Here are some slips, by volume, which I find the easiest way to do it.
All are for leatherhard pots.

Ball Clay 13 parts
Kaolin 3 parts
Silica 2 parts
Pot spar 1 part
Zirconium opacifier 1 part
Bentonite (dry) 1 part



Robin Hopper slip--adapted

Ball clay 63
Kaolin 8
Silica 17
Feldspar 13

I add some zircopax, and have found no difference between types of spar.

Ron Roy on thu 23 oct 03


It is always a good idea to test slips - compare them to the clays you are
going to put them on because there is a wide variation in the clays we make
and buy and they have very different expansions sometimes.

I'm not talking about the drying but the firing.

If your glazes fit your clays then what you need to aim for is to get your
slips to fit your glazes. Easy enough to do - make test tiles out of your
slip clay and put your glazes on them. Every time you change slips or clays
test them - pretty soon you will start getting a feel for this and your
options will begin to expand.

RR


>Ok. I have found that most slips fit commercially made bodies. I
>expect that this is because most of them shrink around 12% and the
>slips can deal with that.
>
>Here are some slips, by volume, which I find the easiest way to do it.
>All are for leatherhard pots.
>
>Ball Clay 13 parts
>Kaolin 3 parts
>Silica 2 parts
>Pot spar 1 part
>Zirconium opacifier 1 part
>Bentonite (dry) 1 part
>
>
>
>Robin Hopper slip--adapted
>
>Ball clay 63
>Kaolin 8
>Silica 17
>Feldspar 13
>
>I add some zircopax, and have found no difference between types of spar.

Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513