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question re: firing of porcelain clay

updated fri 31 may 96

 

Susan Wagener on mon 13 may 96

Being new to this list (and field of pottery), please forgive me if this
question has been asked before...

As I understand it, I have three choices in firing porcelain clay.
1. Low Fire Bisque - High Fire Glaze: which is supposed to make high fire
glazes easy to apply and produce ware without crazing.

2. High Fire Bisque - Low Fire Glaze: Glazes can be difficult to apply.

and

3. Single Fire: Apply high fire glazes to bone dry greenware then single
fire to Cone 5 saving in firing costs.

Does anyone have an opinion on which is the best method or does it matter taking
into account the ease or difficulty of applying glazes. You should also know, I
do not have the luxery of owning a kiln yet...just purchased the wheel a few
weeks ago...so I have to take my wares to another location to fire. The 3rd
(Single fire) method looks most appealing but I don't want to sacrifice quality
for convenience.

Thanks ahead for any advice.

Susan Wagener
Bloomington, IN where the sun is finally helping dry out our soggy back
yard...although three more days of rain this week are in the forcast!

Lisa Skeen on tue 14 may 96

In a message dated 96-05-13 14:50:38 EDT, you write:

> 1. Low Fire Bisque - High Fire Glaze: which is supposed to make high fire
>glazes easy to apply and produce ware without crazing.

This is the technique used in our studio, and it seems to work best.

> 2. High Fire Bisque - Low Fire Glaze: Glazes can be difficult to
apply.

Never heard of this. I'd think the porcelain would vitrify and not take the
glaze very well.

> 3. Single Fire: Apply high fire glazes to bone dry greenware then
single fire to Cone 5 saving in firing costs.

I have been using the Grolleg ^6 porcelain from Kickwheel and have done this
on one or two pieces. I have had a fair number of pieces made from this clay
to crack in the drying process, though, so I don't like to do the single fire
thing to this clay body because it has to be babied so much.

Lisa
>

Michelle H. Lowe on mon 20 may 96

At 9:25 AM 5/14/96 -0400, Lisa Skeen wrote:
>> 2. High Fire Bisque - Low Fire Glaze: Glazes can be difficult to
>apply.
>
>Never heard of this. I'd think the porcelain would vitrify and not take the
>glaze very well.

This is the method that doll makers use when firing and then china painting
slipcast porcelain dolls.

Michelle Lowe, potter in the Phoenix desert \|/ |
mishlowe@indirect.com -O- | |
mishlowe@aztec.asu.edu /|\ | | |
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