Tom Wirt on tue 6 oct 98
>> Hi,
>> I have a few questions.
>>
>> 1. I've been trying to throw the juicer that Minnosota Clay shows on
>> there web page. I've done
>> three of them, but they have all cracked at the bottom around the middle
>> juicer. I imagine this is
>> a stress crack, but I dont know how to prevent it or what I'm doing
>> wrong to cause it. suggestions?
Hi Barney,
I'd guess this is a drying crack, caused by the extra wetness from the thickness
in the center. The outer wall dries first compressing the center clay. Then
when the center clay dries and shrinks it pulls away from the outer dry part.
Similar to wood drying.
I had a similar problem throwing a flat bird feeder with a raised wall in the
center...kind of like some people's chip and dips.
Either dry slowly under some loose plastic (cleaner bag or painters drop cloth)
or try carving the juicing part out from the bottom if it's solid.
Tom
Barney Adams on wed 7 oct 98
I've thrown the 4th attempt at the juicer. I've kept the base thicker this
time and used a white stoneware body. It seems to be better off, but I
wont be sure until I bisque fire it. I have a bique fired hour glass shaped
bat I use to trim bottles. I had used it to hold the juicers upside down
to dry the bottom. I think the bisque may have caused the section to dry
too fast.
Thanks
Barney>
> ----------------------------Original message----------------------------
> >> Hi,
> >> I have a few questions.
> >>
> >> 1. I've been trying to throw the juicer that Minnosota Clay shows on
> >> there web page. I've done
> >> three of them, but they have all cracked at the bottom around the middle
> >> juicer. I imagine this is
> >> a stress crack, but I dont know how to prevent it or what I'm doing
> >> wrong to cause it. suggestions?
> Hi Barney,
>
> I'd guess this is a drying crack, caused by the extra wetness from the thickne
> in the center. The outer wall dries first compressing the center clay. Then
> when the center clay dries and shrinks it pulls away from the outer dry part.
> Similar to wood drying.
>
> I had a similar problem throwing a flat bird feeder with a raised wall in the
> center...kind of like some people's chip and dips.
>
> Either dry slowly under some loose plastic (cleaner bag or painters drop cloth
> or try carving the juicing part out from the bottom if it's solid.
>
> Tom
>
Cindy Morley on thu 8 oct 98
I haven't seen the original that you are trying to replicate (solid
base??), but I have had luck by throwing a two walled piece and coning in
the inner wall until it comes to a point. When it is leather hard I carve
grooves in it. The base is no thicker than on any other pot of mine,
neither are the walls. When I set it out to dry, I usually put it on
little dowels so that air can get up underneath and dry more evenly...
Hope this helps.
P.S. I also use a white stoneware body...
At 07:36 AM 10/7/98 , you wrote:
>----------------------------Original message----------------------------
>I've thrown the 4th attempt at the juicer. I've kept the base thicker this
>time and used a white stoneware body. It seems to be better off, but I
>wont be sure until I bisque fire it. I have a bique fired hour glass shaped
>bat I use to trim bottles. I had used it to hold the juicers upside down
>to dry the bottom. I think the bisque may have caused the section to dry
>too fast.
>
>Thanks
>Barney>
>> ----------------------------Original message----------------------------
>> >> Hi,
>> >> I have a few questions.
>> >>
>> >> 1. I've been trying to throw the juicer that Minnosota Clay shows on
>> >> there web page. I've done
>> >> three of them, but they have all cracked at the bottom around the middle
>> >> juicer. I imagine this is
>> >> a stress crack, but I dont know how to prevent it or what I'm doing
>> >> wrong to cause it. suggestions?
>> Hi Barney,
>>
>> I'd guess this is a drying crack, caused by the extra wetness from the
thickne
>> in the center. The outer wall dries first compressing the center clay.
Then
>> when the center clay dries and shrinks it pulls away from the outer dry
part.
>> Similar to wood drying.
>>
>> I had a similar problem throwing a flat bird feeder with a raised wall
in the
>> center...kind of like some people's chip and dips.
>>
>> Either dry slowly under some loose plastic (cleaner bag or painters drop
cloth
>> or try carving the juicing part out from the bottom if it's solid.
>>
>> Tom
>>
>
~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~
Cindy Morley Shire-March of the Grimfells
HL Christean Jansen Kingdom of Calontir
Use the talents you possess; for the woods would be very silent if no
birds sang except the best.
http://comp.uark.edu/~cmorley cmorley@comp.uark.edu
~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~
Tom Wirt on fri 9 oct 98
-----Original Message-----
Subject: Re: drying problem
I have a bique fired hour glass shaped
bat I use to trim bottles. I had used it to hold the juicers upside down
to dry the bottom. I think the bisque may have caused the section to dry
too fast.
Thanks
Barney>
> ----------------------------Original message----------------------------
Barney, another idea on drying unusual shapes that I've used, Get some 2" foam
at a fabric store. Cut whatever out of the foam to support whatever you're
drying. The foam will let some moisture out without over drying or twisting the
pot or munching the surface texture.
Tom
Bonnie Staffel on mon 12 oct 98
----------------------------Original message----------------------------
>
> -----Original Message-----
> Subject: Re: drying problem
>
>
> I have a bique fired hour glass shaped
> bat I use to trim bottles. I had used it to hold the juicers upside down
> to dry the bottom. I think the bisque may have caused the section to dry
> too fast.
>
> Thanks
> Barney>
> > ----------------------------Original message----------------------------
>
>
> Barney, another idea on drying unusual shapes that I've used, Get some 2" foam
> at a fabric store. Cut whatever out of the foam to support whatever you're
> drying. The foam will let some moisture out without over drying or twisting t
> pot or munching the surface texture.
>
> Tom
>
>Whenever I make plates or any form which might
give trouble in drying, I apply a coat of waterwax
on the exposed rim of the pot, even handles. I
use a slip
trail squeezable bottle and a brush always kept in
a container of water. This is squirted or trailed
wherever you wish the wax, then with the brush, it is spread out as the wheel is
done as soon as the pot is finished and still on the wheel.
For good bottoms before glazing bisque, I use the same bottle and brush method,
Seems that water wax doesn't give off the fumes
in the kiln as much as the petroleum hot wax.
Bonnie Staffel
bstaffel@freeway.net
-----
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