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horse hair cracking

updated thu 22 nov 01

 

Bruce and Lynne Girrell on mon 19 nov 01


Robert Izzi wrote:

> I have having a problem with my pot cracking near the lip of my pot
> when I am appling the hair.

We had a lot of cracking when we started doing horsehair decoration. We are
using a porcelainous clay body which exacerbated the problem. Two things
seem to have helped. First, we have added about 5% pyrophyllite to the clay
body. The other change (which I accidentally did at the same time, so I'm
not sure which has had the most effect) is that I lowered our bisque
temperature from ^06 to ^08, sometimes even as low as ^010.

We rarely have any cracking now. I might also add that we burnish our pots
and I believe that burnishing the trimming tool marks and other stress
risers out of the surface helps eliminate crack initiation.

Good luck.

Bruce Girrell
in snowy Kazakhstan

Marcia Selsor on mon 19 nov 01


Turn it upside down. It will cool slower.
Marcia In Montana
(my physicist husband was watching me and I had the same thing. He
suggested this and it works great)

Robert Izzi wrote:
>
> Holle, I have having a problem with my pot cracking near the lip of my pot
> when I am appling the hair. Any suggestions? I have tried just about
> everything I can think of to correct the cracking.
>
> Thanks Bob
>
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--
Marcia Selsor
selsor@imt.net
http://www.imt.net/~mjbmls
http://www.imt.net/~mjbmls/Tuscany2002.html

Robert Izzi on mon 19 nov 01


Holle, I have having a problem with my pot cracking near the lip of my pot
when I am appling the hair. Any suggestions? I have tried just about
everything I can think of to correct the cracking.

Thanks Bob

Robert Izzi on tue 20 nov 01


Thanks for the info,I have been bisquing my pot to cone 04 and 06 . I am
going to try lowering my bisque.

Thanks again