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wood ash prep

updated wed 10 dec 03


Bonita Cohn on fri 12 feb 99

I calcine the ashes in a bisque bowl (another crack pot have value) That is,
I window screen off any big stuff and put it thru a bisk fire to complete the
burning. Then it can be used as is in a recipe. Try half clay, half as..h.
plus a little ochre..Some people wash the ash. I find this "dry" methods works
Bonita in crispy San Francisco.

dneese on tue 9 dec 03

If your are going to wash the wood ash for use in glazes, wash as much as
you can the first time to make the task worthwhile. Be sure of your source
for "cleaner" ash. If you don't you may not know what trash was burnt along
with the wood. The best source is burning your own wood, preferably one
species of wood. I know this sounds somewhat strict but the quality of your
glaze results will be much better and washing will be less of a chore. I
tend a clean fireplace during the winter using only oak. Using a grate the
wood is almost completely ash with little or no unburned pieces. I hardly
need to screen or wash it is so clean and fluffy. If you don't have a
fireplace, make a hard firebrick pad on the ground, burn your wood on top.
To wash you wood ash, (usual safety precaution apply), use a big wash tub
slightly tilted to one side. Add water to the ash and stir, most unburned
particles will float to the top. Rake the particles off the top. Have
another tub with a window screen in a wood frame over it to pour and sieve
the wet suspension through. You could sieve further in a smaller mesh sieve
to reduce the particle size even more. Let it sit and settle. Decant the
water off as much as possible. If you let this remainder in the tub sit for
a few days to dry some it will cake up. Dump the chunks out on a tarp in the
sunshine until dry and crumbles to powder. Remove to storage containers and
Then when using wood ash in a glaze it believe it is wise not to mix a huge
amount. No more than 5 gallons. Sieve the glaze several times to completely
mix and remove larger particles. Wood ash glazes change the longer it sits.
The fired results are variable over time. Some times good sometimes bad.
Just my experience.

Dale Tex
"across the alley from the Alamo"
San Antonio, Texas USA