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fused porcelain and glaze fit

updated thu 31 jul 03

 

Craig Martell on mon 28 jul 03


Hi:

There have been some discussions about making porcelain bodies lately so I
thought I might throw in one more thing I've been looking at. I'll keep
this real short though.

There's a big difference with the vitrirication of stoneware and porcelain
bodies. Since porcelain is very low in iron, it's possible to take the
vitrification to the zero point with good advantage. You then have a
glassy, fused body with a lower expansion than a more crystalline body with
a slight percentage of absorbtion. Glazes will fit better. My recent
experiments with several different porcelain bodies are telling me that
this is indeed the case. Before I forget, I am firing this stuff to cone
10 reduction.

More info later, followed by a myriad of rumors.

Craig Martell Hopewell, Oregon

David Beumee on tue 29 jul 03


7/28/03 9:20:57 PM, Craig Martell wrote:
You then have a
>glassy, fused body with a lower expansion than a more crystalline body with
>a slight percentage of absorbtion. Glazes will fit better.

A wonderful insight on the difference between stoneware and porcelain.
I've managed to formulate a rather high percentage of high expansion
glazes, because I have had to lower the expansion of several glazes to fit the
lower expansion porcelain clay that I now realize becomes so simply by virtue
of it being porcelain.

David Beumee
Earth Alchemy Pottery
Lafayette, CO

>Hi:
>
>There have been some discussions about making porcelain bodies lately so I
>thought I might throw in one more thing I've been looking at. I'll keep
>this real short though.
>
>There's a big difference with the vitrirication of stoneware and porcelain
>bodies. Since porcelain is very low in iron, it's possible to take the
>vitrification to the zero point with good advantage. You then have a
>glassy, fused body with a lower expansion than a more crystalline body with
>a slight percentage of absorbtion. Glazes will fit better. My recent
>experiments with several different porcelain bodies are telling me that
>this is indeed the case. Before I forget, I am firing this stuff to cone
>10 reduction.
>
>More info later, followed by a myriad of rumors.
>
>Craig Martell Hopewell, Oregon
>
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