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ash glace pudding

updated thu 25 apr 02


Keramik Burger on wed 24 apr 02

I am using an ash-glace (about 50% mixed ash, mainly pine). And now I
started a new bunch of ash the glace is like custard, and not
drying on the pots.
I washed the ash before, but anyhow it is very soapy.

It never happened before. Does anyone now that effect and how to handle it?

Best wishes from Germany.
Ralf Burger

Craig Martell on wed 24 apr 02

Guten Tag Ralf:

The ash has a lot of soluble alkali which is causing the glaze to
thicken. Once the glaze is mixed and you start having this problem there
is very little you can do to correct it. If you add more water to make the
glaze fluid your application will be too light and your glaze won't have
the thickness of application that you need.

You could try adding a deflocculant such as sodium silicate to try and
restore the fluidity but I'm not sure if this will work. Try a small batch
and see if things improve.

If you have more of this particular wood ash, wash it more, until the water
doesn't feel slick and soapy and the lye smell is gone from the
water. This will get rid of the solubles and you won't have the pudding
problem any longer.

Another way to approach this if you want to keep some of the soluble fluxes
is to mix just enough glaze to do the pots you have and don't let the glaze
sit very long. Use all the glaze quickly.

regards, Craig Martell in Oregon