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fatten up the slip a bit?

updated tue 15 may 01

 

Tony Ferguson on fri 11 may 01


Add 2% bentonite. That should do it.

Tony, Duluth MN




--- Hudson Mackenzie wrote:
> from jon whitney (nodicaprio@yahoo.com) via
> hudson@potters.org
>
> I having some trouble with my throwing slip
> cracking. It is a nice white slip base that we apply
> to the pieces right after throwing. The slip fits
> the body well when thin or medium, but has had a low
> succes rate at the thicker levels. We do use sodium
> silicate and I am currently testing with some cmc
> added to the mix, but was wondering about
> pyrotholite or any other ideas ? wonderful spring
> between the lakes
>
>
_________________________________________________________________________=
_____
> Send postings to clayart@lsv.ceramics.org
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> reached at melpots@pclink.com.


=3D=3D=3D=3D=3D
--Tony Ferguson, fergyart@yahoo.com315 N. Lake Ave. Apt 401Duluth, MN 55=
806(218) 727-6339Looking to see, buy or barter artwork go to:http://acad.=
uwsuper.edu/www/aferguso/fergyart.htm

Hudson Mackenzie on fri 11 may 01


from jon whitney (nodicaprio@yahoo.com) via hudson@potters.org

I having some trouble with my throwing slip cracking. It is a nice white slip base that we apply to the pieces right after throwing. The slip fits the body well when thin or medium, but has had a low succes rate at the thicker levels. We do use sodium silicate and I am currently testing with some cmc added to the mix, but was wondering about pyrotholite or any other ideas ? wonderful spring between the lakes

Marcia Selsor on sat 12 may 01


Vinegar will fatten up your slip.
Marcia in Montana

Hudson Mackenzie wrote:
>
> from jon whitney (nodicaprio@yahoo.com) via hudson@potters.org
>
> I having some trouble with my throwing slip cracking. It is a nice whit=
e slip base that we apply to the pieces right after throwing. The slip fi=
ts the body well when thin or medium, but has had a low succes rate at th=
e thicker levels. We do use sodium silicate and I am currently testing wi=
th some cmc added to the mix, but was wondering about pyrotholite or any =
other ideas ? wonderful spring between the lakes
>
> _______________________________________________________________________=
_______
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at melpots@pcl=
ink.com.

--
Marcia Selsor
selsor@imt.net
http://www.imt.net/~mjbmls
http://www.imt.net/~mjbmls/Tuscany2001.html
http://www.imt.net/~mjbmls/Gallery.html

Bruce Girrell on sat 12 may 01


On Fri, 11 May 2001 21:53:03 -0400, you wrote:

>I having some trouble with my throwing slip cracking.

=3D46rom the symptoms that you describe, it sounds as though the slip has
a higher shrinkage than the base clay. That implies that you need to
reduce the shrinkage of your slip by eliminating ingredients such as
bentonite (I know, someone else told you to _add_ bentonite - such is
the way of free advice). Since it is a white slip you might substitute
kaolin*.

Alternatively, and possibly easier, you might consider increasing the
shrinkage of your main clay body by adding a high shrinkage material
such as bentonite. Of course, this brings with it the possibility of
an increased rate of cracking in your ware.

You may be able to get some more specific suggestions if you tell us
the composition of your clay body and slip.

Bruce Girrell
in northern Michigan where it is cool but sunny and I'm just reading
the mail before going down to try my hand at some pots today.


*You can go too far with the addition of kaolin, though, and this
could also be a part of your problem. If the proportion of kaolin is
too high, the slip will have no mechanical strength of its own and
will crack as a result.=3D20

One time just to see what would happen, I threw a pot made from 100%
EPK. Shaping it was not too bad, though I did see some signs of
weakness. When the pot dried and I trimmed it, it looked perfect.
After the bisque firing, though, it was a mass of cracks.

Nils Lou on sun 13 may 01


I've found artists' acrylic polymer medium (one tbls/quart makes a nice
thickner. nils

On Sat, 12 May 2001, Marcia Selsor wrote:

> Vinegar will fatten up your slip.
> Marcia in Montana
>
> Hudson Mackenzie wrote:
> >
> > from jon whitney (nodicaprio@yahoo.com) via hudson@potters.org
> >
> > I having some trouble with my throwing slip cracking. It is a nice white slip base that we apply to the pieces right after throwing. The slip fits the body well when thin or medium, but has had a low succes rate at the thicker levels. We do use sodium silicate and I am currently testing with some cmc added to the mix, but was wondering about pyrotholite or any other ideas ? wonderful spring between the lakes
> >
> > ______________________________________________________________________________
> > Send postings to clayart@lsv.ceramics.org
> >
> > You may look at the archives for the list or change your subscription
> > settings from http://www.ceramics.org/clayart/
> >
> > Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
>
> --
> Marcia Selsor
> selsor@imt.net
> http://www.imt.net/~mjbmls
> http://www.imt.net/~mjbmls/Tuscany2001.html
> http://www.imt.net/~mjbmls/Gallery.html
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
>

Mark Lendsey on mon 14 may 01


I have tried adding bentonite to fatten slips.
Put water in a blender add bentonite to slip wet.
It does not take much to get results.

On Sun, 13 May 2001 13:31:25 -0700 Nils Lou writes:
> I've found artists' acrylic polymer medium (one tbls/quart makes a
> nice
> thickner. nils
>
> On Sat, 12 May 2001, Marcia Selsor wrote:
>
> > Vinegar will fatten up your slip.
> > Marcia in Montana
> >
> > Hudson Mackenzie wrote:
> > >
> > > from jon whitney (nodicaprio@yahoo.com) via hudson@potters.org
> > >
> > > I having some trouble with my throwing slip cracking. It is a
> nice white slip base that we apply to the pieces right after
> throwing. The slip fits the body well when thin or medium, but has
> had a low succes rate at the thicker levels. We do use sodium
> silicate and I am currently testing with some cmc added to the mix,
> but was wondering about pyrotholite or any other ideas ? wonderful
> spring between the lakes
> > >
> > >
>
_________________________________________________________________________
_____
> > > Send postings to clayart@lsv.ceramics.org
> > >
> > > You may look at the archives for the list or change your
> subscription
> > > settings from http://www.ceramics.org/clayart/
> > >
> > > Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
> >
> > --
> > Marcia Selsor
> > selsor@imt.net
> > http://www.imt.net/~mjbmls
> > http://www.imt.net/~mjbmls/Tuscany2001.html
> > http://www.imt.net/~mjbmls/Gallery.html
> >
> >
>
_________________________________________________________________________
_____
> > Send postings to clayart@lsv.ceramics.org
> >
> > You may look at the archives for the list or change your
> subscription
> > settings from http://www.ceramics.org/clayart/
> >
> > Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
> >
>
>
_________________________________________________________________________
_____
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your
> subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
>
________________________________________________________________
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