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large bubbles

updated sun 11 dec 05

 

Jacqueline Miller on thu 8 dec 05


A fellow student applied slip to cone 6 Standard clay body that usually
takes this slip well. It looked fine after the bisque. She put on a satin
clear that has been fine in the past. The piece came out with large bulbous
bubbles. She broke the piece and the clay looked fine but the slip plus
glaze layer had lifted off to make the bubble. The instructor thought the
clay may have been contaminated with a low fire clay. She expected to see
bubbling of the clay itself but there was none. Any thoughts? Could the cla=
y
have been contaminated, not bubble but rather just shrink more causing the
slip and glaze not to fit?

Ruth Ballou on fri 9 dec 05


How and when was the slip applied? Was it brushed on or dipped and
poured? Was the pot leather hard or bone dry? Slip has the best
chance of adhering when it is applied no later than leather hard.
Some slips may adhere better if they are brushed on rather than dipped.

Ruth Ballou
Belgium


On Dec 9, 2005, at 3:36 AM, Jacqueline Miller wrote:

> A fellow student applied slip to cone 6 Standard clay body that
> usually
> takes this slip well. It looked fine after the bisque. She put on a
> satin
> clear that has been fine in the past. The piece came out with large
> bulbous
> bubbles. She broke the piece and the clay looked fine but the slip
> plus
> glaze layer had lifted off to make the bubble. The instructor
> thought the
> clay may have been contaminated with a low fire clay. She expected
> to see
> bubbling of the clay itself but there was none. Any thoughts? Could
> the clay
> have been contaminated, not bubble but rather just shrink more
> causing the
> slip and glaze not to fit?
>
> ______________________________________________________________________
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> Send postings to clayart@lsv.ceramics.org
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>

Jacqueline Miller on sat 10 dec 05


It was brushed on at leather hard. I think she put on three coats.
Jackie


On 12/9/05, Ruth Ballou wrote:
>
> How and when was the slip applied? Was it brushed on or dipped and
> poured? Was the pot leather hard or bone dry? Slip has the best
> chance of adhering when it is applied no later than leather hard.
> Some slips may adhere better if they are brushed on rather than dipped.
>
> Ruth Ballou
> Belgium
>
>
> On Dec 9, 2005, at 3:36 AM, Jacqueline Miller wrote:
>
> > A fellow student applied slip to cone 6 Standard clay body that
> > usually
> > takes this slip well. It looked fine after the bisque. She put on a
> > satin
> > clear that has been fine in the past. The piece came out with large
> > bulbous
> > bubbles. She broke the piece and the clay looked fine but the slip
> > plus
> > glaze layer had lifted off to make the bubble. The instructor
> > thought the
> > clay may have been contaminated with a low fire clay. She expected
> > to see
> > bubbling of the clay itself but there was none. Any thoughts? Could
> > the clay
> > have been contaminated, not bubble but rather just shrink more
> > causing the
> > slip and glaze not to fit?
> >
> > ______________________________________________________________________
> > ________
> > 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.
>