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using dry wood ash

updated fri 8 jun 07


Dale Neese on thu 7 jun 07

Dan and all,
First I'd like to acknowledge Dick Lehman and his CM article for using dry
wood ash on his side fired vessels. His work is the source of my creative
inspirations in this particular method.
Secondly the quality of the wood ash has so much to do with the fired
results. When several student in my class at school started using their own
wood ash I noticed a wide range of results, one of them being the problem
Dan mentioned of the gritty particles on the surface after firing. I don't
believe that the glaze frit has anything much at all to do with the problem.
I believe the wood ash is much more noticeable on the smooth translucent
quality of a celadon glaze on a light firing clay body such as porcelain. We
are all encouraged to experiment and test, however to me, traditionally
speaking a lovely celadon glaze should be used and shown for it's own

I suspect that the problem is collection of the wood ash and contaminated
with sand like particles from the surface of the ground. Seeing this type
problem before with the students I asked where did you get your wood ash?
Some were given the wood ash from a neighbor's fireplace not knowing the
origin of the wood and other combustibles contained . Some thought it was
wood ash from an outdoor fire perhaps containing items other than wood, a
backyard barbeque grill. Their results were as different as the different
sources and type of their wood ash. I think also that washing would leave
more of the smaller, heavier sand like particles in the processed wood ash.

For my consistent predictable results with wood ash, I use only the wood ash
that I completely burn in a controlled burn. In my fireplace. We don't burn
a lot of firewood here in South Texas over the winter except maybe for
cooking a side of beef for Thanksgiving. I use a heavy iron grate in my
fireplace avoiding flaking of metals or rust particles. I burn only the same
oak hard wood harvested off my property. I have a floor damper control
inside the fireplace that allows me to increase the air flow under the grate
to get a hotter combustion. The resulting wood ash is white and fluffy.
Hardly any un-burnt residue to sieve out. Pure. A five gallon bucket will
last a long time. I also use unwashed wood ash in my ash glazes.

Third suggestion is the application of the wood ash and when it is applied
to the glaze. If you read the Dick Lehman article in Ceramics Monthly you
will see the photo of Dick using a kitchen sieve to apply the wood ash.
Right there you know how to apply the wood ash. How much to apply is your
call. Protect your shelves.

Good luck Dan and all with your experiments,

Dale Tex
"across the alley from the Alamo"
San Antonio, Texas USA
I will be attending game one tonight!!