Mary Higgins on fri 15 feb 02
Mel,
I live just over an hour South of Axner's. They are in Oviedo, which is =
just East of Orlando. I would like to help test the new clay, if it is =
cone 6. My elderly kiln is rated to 2300 F, but I don't want to go =
higher than about cone 6 or 7.
Thanks,
Mary in Central Florida.
mhiggins@ithink.net
Khaimraj Seepersad on sun 17 feb 02
Hello to All ,
Gavin ,
I have some experience with the 40 to 60 %
Talc and ball clay bodies fired to cone 04 .
If there is too much talc , after 6 months to a
year , the body actually powders , especially
under moist or wet conditions.
Very few glazes held on this body [ cone 06 types]
developing cracks and moss lines.
[ used as a casting body ]
Also glazes often came of in flakes, as there seemed
to be no or little interaction between the body
and glaze.
Even the silly figurines developed cracks with
time in the glaze.
Seems to need some frit to help the talc.
However , when using the Behrens' recipe for
cone 04 [ soft stone ware ] , results were very
different.
Adaptation , because of shipping costs, led
to a body of 40 % cullet to 60 % clay .
Our off - white clays , requiring a higher temperature
of 06 to 05 and red earthenware needing 08.
Combinations of 20 Talc / 20 Cullet / 60 clay
produced a higher firing body and at that time
- INFINITY [ commercial clear glaze for 06 and
above ] - seemed to fit perfectly.
[ seemed - because no tests were done on this
glaze , nor was it ever used ].
By that time I had wondered of into the world of
local clays and my own home-made frits and
home made glazes.
I was already burning and calcining ash for mixing
with B203 to create clear ash based frits.
[ 100 % mango - 100 % malphigia - 100 % poui
and so on , as well as 100 % soft stemmed garden
weeds , also 100 % banana peels ].
The talc / cullet / clay mixes , if using off white clays
could be made to be very plastic with additions of
a very plastic red earth clay , producing a yellow
type body.
My sister did throw some simple bowls , and a few
vases , but a more experienced potter considered
this body to be very "thirsty".
As usual with cullet bodies , the batches set to rock
hard within 2 or 3 days, so we prepared small batches
[ less than 20 lbs ] daily , resting the mix for two to
three hours before kneading for use.
This was washed and dried cullet . So a % of Na20 was
still able to leach out.
Wares produced were vitreous , probably through glass
bonding . Test was a white napkin , left under a bowl
for 24 hours. The bowl being filled with water coloured
deep blue with food colouring .
This was before glazing.
I don't know if this is of any use to you or anyone , but
I offer it none the less.
Khaimraj
* there are also recipes for low firing translucent and
bone ash clay bodies.
-----Original Message-----
From: Gavin Stairs
To: CLAYART@LSV.CERAMICS.ORG
Date: 18 February 2002 3:35
Subject: Clayart body
>How come nobody's stepped up with any suggestions?
>
>How about this: I suppose we consider at least three bodies: an
>earthenware, a mid-range stoneware, and a high range stoneware or
porcelain.
>
>The earthenware: possibilities:
> E1: a high talc, white body, made with about 40-60% talc and a mix of
>white burning ball clays.
> E2: a high talc, red burning body with a bit less talc and a mix of
>ball clay and high iron clay.
> E3: a high iron body, with little flux other than the natural clays.
>Of these, the high talc white would be the easiest to control, I suspect.
>
>The midrange possibilities:
> M1: a buff or light ball and refractory clay body.
> M1i: with flecks of iron
> M1g: with refractory sand (kyanite?)
> M2: a dark body using iron containing fireclays
> M2i: with big flecks of iron
> M3: a porcelain using mostly kaolin and fluxes.
>The subcategories can multiply rapidly, so we need to be careful here. I
>don't want to define the body by the amendments it carries, although that
>is often the case in commercial bodies. Here, the base recipe should be
>defined on materials of high consistency and wide availability, rather than
>on their "interesting" character.
>
>The high range:
> H1: a white to buff stoneware
> H2: a titanium bearing porcelain
>
>Other variants come to mind: casting bodies for slips, hand working and
>throwing variants, etc.
>
>Ok: which of these, or others, are the best candidates, and what materials
>should be used? The materials should not be based on cost, but on
>consistency and wide availability.
>
>My guess is that most of the Clayart members use mid-range stoneware, and
>fire to c5-6. They throw, rather than cast or hand build. They like a
>clay with a slight tooth, but not too much. They don't like iron
>spots. For them, a mix of ball clay, kaolin, flux and sand.
>
>Then there are the fire worshippers who like mainly C10 stone with the
>bones sticking out, and lots of freckles. For them, kaolin, ball and sand,
>with dirt added, and a bit of feldspar.
>
>What happens first?
>
>Gavin, intrigued in London, Ont.
>
>At 10:54 PM 17/02/2002 -0600, you wrote under Re: mel's bias:
>>it would naturally be assumed that if we
>>publish the recipe on the box, that everyone
>>in the world would have the use of the clay body
>>to make, or use, or manufacture.
>
>___________________________________________________________________________
___
>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.
>
Gavin Stairs on mon 18 feb 02
How come nobody's stepped up with any suggestions?
How about this: I suppose we consider at least three bodies: an
earthenware, a mid-range stoneware, and a high range stoneware or porcelain.
The earthenware: possibilities:
E1: a high talc, white body, made with about 40-60% talc and a mix of
white burning ball clays.
E2: a high talc, red burning body with a bit less talc and a mix of
ball clay and high iron clay.
E3: a high iron body, with little flux other than the natural clays.
Of these, the high talc white would be the easiest to control, I suspect.
The midrange possibilities:
M1: a buff or light ball and refractory clay body.
M1i: with flecks of iron
M1g: with refractory sand (kyanite?)
M2: a dark body using iron containing fireclays
M2i: with big flecks of iron
M3: a porcelain using mostly kaolin and fluxes.
The subcategories can multiply rapidly, so we need to be careful here. I
don't want to define the body by the amendments it carries, although that
is often the case in commercial bodies. Here, the base recipe should be
defined on materials of high consistency and wide availability, rather than
on their "interesting" character.
The high range:
H1: a white to buff stoneware
H2: a titanium bearing porcelain
Other variants come to mind: casting bodies for slips, hand working and
throwing variants, etc.
Ok: which of these, or others, are the best candidates, and what materials
should be used? The materials should not be based on cost, but on
consistency and wide availability.
My guess is that most of the Clayart members use mid-range stoneware, and
fire to c5-6. They throw, rather than cast or hand build. They like a
clay with a slight tooth, but not too much. They don't like iron
spots. For them, a mix of ball clay, kaolin, flux and sand.
Then there are the fire worshippers who like mainly C10 stone with the
bones sticking out, and lots of freckles. For them, kaolin, ball and sand,
with dirt added, and a bit of feldspar.
What happens first?
Gavin, intrigued in London, Ont.
At 10:54 PM 17/02/2002 -0600, you wrote under Re: mel's bias:
>it would naturally be assumed that if we
>publish the recipe on the box, that everyone
>in the world would have the use of the clay body
>to make, or use, or manufacture.
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