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freeze resistant ceramics

updated thu 1 feb 07

 

Phyllis Tilton on tue 23 jan 07


I am not sure if I read about restoration in a ceramic mag, archeological mag or other, but it was quite interesting to see how the restorers made mold to replicate the weather worn parts on historic buildings. The scaffolds constructed to get them up to the rooftops were awesome. As I remember, work I read about was in New England.

Now, I will bring up another aspect about outdoor art work--that of the use of resins. I have never used resin but have read about someone doing that for sculptures or other meant to be in the gardens year round. Seems that one person mixed resin with clay. I am not sure what resin is--haven't been interested enough to research it, I guess. Not sure where to buy it either, but have put that on a very far back burner til the time I have more time to get into some other methods. Can resin be fired?? Is it a vegetable product---I think of resins as being an exudation from a tree.

One of my faults, I don't stick with the same methods all the time---want to try everything. I guess that isn't all bad.

Phyllis Tilton
daisypet1@yahoo.com

Snail Scott on wed 24 jan 07


At 05:25 AM 1/23/2007 -0800, you wrote:
>...I have never used resin but have read about someone doing that for
sculptures or other meant to be in the gardens year round. Seems that one
person mixed resin with clay. I am not sure what resin is--haven't been
interested enough to research it, I guess. Not sure where to buy it either,
but have put that on a very far back burner til the time I have more time
to get into some other methods. Can resin be fired?? Is it a vegetable
product---I think of resins as being an exudation from a tree.


Resin is a term describing a class of
materials with similiar polymeric properties.
They are 'organic' in the organic-chemistry
sense of the word - carbon-based compounds.
While some are plant-derived, the kind you are
referring to - the sort often used for mass-
produced lawn ornaments - is a plastic resin,
a type of injection-molded or cast epoxy. If
fired, it will melt. Clay (dry, not wet) might
be added to it as inert solids. 'Cold-cast'
bronze , for instance, is resin mixed with
metal powder to make the result look metallic,
and 'cast stone' is usually resin mixed with
stone powder to make fake marble effect, etc.

You cam buy casting resin (usually polyester
resin, though there are others) in cans at
art-supply and hobby stores, though the packages
are small and the cost is high. If you want to
cast resin in quantity, seek an industrial
supplier for larger quanities - there are ads
in the back of Sculpture Magazine for such
products. Douglas and Sturgess, a sculpture
supply house in San Francisco, has some good
info on their website, http://www.artstuf.com

Be aware - these are petrochemicals, and not
non-toxic. The fumes are fairly nasty, and even
being outdoors is not sufficient guarantee of
fresh air unless it's windy. Indoors, you will
need a spray-booth type fume-removal ventilation
system.

Resin does have its merits, though. Some things
it can offer that clay doesn't: transparency
and resilience.

-Snail

Eleanora Eden on wed 31 jan 07


My understanding is that the porosity is independent of the absorbency.
No matter what the level of absorbency, the saturation coefficient of .78
means simply that more saturation occurs when the sample is boiled.

That is what the idea of using cellulose to add voids is all about, as it
is independent of how vitreous the particular body will get, it will be
adding a system of voids to the clay, so that boiling will make the body
absorb enough more than the soaking that this saturation coefficient
will come down. In most of my tests it comes in at .85-.95. The
added ability to absorb doesn't have to be all that much to get it below
.78 from .85 or so.

One other point to add is that I tested all my clay materials and found
that PV clay came in (these are ^3 tests) at .68 and Roseville clay
came in at .817. So these would be good materials to consider when
looking for such a body. These are just one test of one sample so I
don't consider it a scientific norm or anything but it is an indication that
these materials are naturally more porous than most we use.

Eleanora

--
Bellows Falls Vermont
www.eleanoraeden.com