Vince Pitelka on sun 8 aug 04
> 1. Use a fireclay mixed with sawdust for wadding- Be generous on the
sawdust
> 2 or 3 sawdust to one fireclay. Pops off easy. Alumina in that hot part
of
> the woodkiln fluxes and pulls big chunks outta the pots.
Tony -
I have heard that about the sawdust and fireclay mixture, and now perhaps it
is finally sinking in. But who can explain to both you and me about the
alumina wadding. I mean, there is no chance in hell (yes, even in hell)
that it is fluxing, so what is happening? Is it just that the alumina/china
clay wadding remains TOO porous and simply absorbs the drippy ash like a
sponge? I suspect that is what is happening. At any rate, it certainly
does turn into the hardest substance every known to human civilization next
to diamond, and it ain't brittle like a diamond, so it is hell to get it off
there except with diamond-impregnated cutting/grinding media. If you could
control the ash to drip evenly on three alumina/china clay wads, you'd have
great rock-hard feet, but none of us really want to control our wood kilns
to that degree. So I'm switchin' to fireclay/sawdust wadding in wood.
- Vince
Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
clennell on sun 8 aug 04
Sour Cherry Pottery
>> 1. Use a fireclay mixed with sawdust for wadding- Be generous on the
> sawdust
>> 2 or 3 sawdust to one fireclay. Pops off easy. Alumina in that hot part
> of
>> the woodkiln fluxes and pulls big chunks outta the pots.
>
> Tony -
> I have heard that about the sawdust and fireclay mixture, and now perhaps it
> is finally sinking in. But who can explain to both you and me about the
> alumina wadding. I mean, there is no chance in hell (yes, even in hell)
> that it is fluxing, so what is happening? Is it just that the alumina/china
> clay wadding remains TOO porous and simply absorbs the drippy ash like a
Vince: In long firings or wood firings with lots of ash the free alumina
tends to fuse to the well fluxed bodies and like you say needs to be cut off
with a diamond saw.
Be sure to mix the fireclay and sawdust dry and then add water other wise
you just won't be able to wedge in enough sawdust. You will also find you
also a nice fireclay leaves a red blush instead of the horrid white
snowballs. In Canada wher any reminder of snow is a bad one.
Cheers and good fire!
Tony
Tony and Sheila Clennell
Sour Cherry Pottery
4545 King Street
Beamsville, Ontario
CANADA L0R 1B1
http://www.sourcherrypottery.com
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