Leland G. Hall on thu 31 oct 02
On Thu, 31 Oct 2002 15:22:56 EST, WHC228@AOL.COM wrote:
>A further note.
>The clay that I use seems to have a longer working life than without it.
>I.e. I am able to get a couple of more pulls out of my porcelain than I
could
>without it before I get to the point where it loses its strength. I assume
>that it is because I can use less water in the porcelain to get the same
>plasticity. I also seem to be able to get bolder shapes.
>This is not a recommendation for anyone else. I do filter press my clay,
and
>I do age it as a slurry for at least a week before it goes to the filter
>press. This is an excellent way to make clay, however it does require that
>you have all of the expensive equipment that I have, and the space to put
it
>in.
>Bill
>
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Hi Bill. I have been following the glycerin thread with interest, and may
try it in a clay body. I hope you will pardon my ignorance, but I am
wondering what a "filter press" is. I can easily imagine its use, but I am
hoping you can enlighten me with some details. Thanks in advance.
Best Regards
Leland Hall
La Pine, Oregon, USA
BVCuma on thu 31 oct 02
A further note...
Having found a strong marbling effect
of two distinct green and brown colorations
upon wedging...
After slicing open, down the middle
a second "ball" of 20 day old clay...
finding 24 hours later that the green
colouration had changed into brown
on the freshly exposed surfaces.
On quartering the mass with a second slice...
the color penetration was seen to be 2-3 mm deep..
The ball was stored in black plastic..
so minimal light was involved
and the slice clay was not "sandwiched" back tight
but left somewhat loose...
somesort of oxidation process?
Further investigation revealed
that glycerine has antibacterial qualities..
and provides fermentation nutrients.
I assume algae or something or other
is growing in fact feeding on the glycerine
yet a breakdown of organic metabolites
could be "happening"...not sure.
Furthermore...
As glycerine acts as a water attractant and lubricant...
As it is claimed to be a "bodying agent"
I have noted it does feel more firm and responsive
while in a very soft state of working consistency...
This is a very nice quality.
As it is used as a stool softener (please no bathroom humor ; )
it attracts water and yet softens... shall we say the "medium"
This somehow can be seen as a similar model
of how the compound helps plasticize yet dehydrate while lubricating.
Yet the most interesting thing is the advanced onset of souring.
As of yet unresolved concepts...
Any clarification or further suppositions appreciated
regards,
Bruce
WHC228@AOL.COM on thu 31 oct 02
A further note.
The clay that I use seems to have a longer working life than without it.
I.e. I am able to get a couple of more pulls out of my porcelain than I could
without it before I get to the point where it loses its strength. I assume
that it is because I can use less water in the porcelain to get the same
plasticity. I also seem to be able to get bolder shapes.
This is not a recommendation for anyone else. I do filter press my clay, and
I do age it as a slurry for at least a week before it goes to the filter
press. This is an excellent way to make clay, however it does require that
you have all of the expensive equipment that I have, and the space to put it
in.
Bill
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