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updated sat 5 dec 09


Malone & Dean McRaine on sat 26 apr 97

Aloha ClayArters and Arteresses. I should know the answer to this but my
thinking is muddled today. Does deflocculating a glaze alter the thickness
of the application on the pot? I have a glaze with Gerstley Borate in it
that doesn't flow enough to fill in all the detailed surface decoration on
my pots. I can't water it down or it will be too thin. If I deflocculate
it, will I have to reduce the water content to get the same thickness of
application? Any suggestions on deflocculants will be helpful too.

With Aloha blessings,

lili krakowski on fri 4 dec 09

Ulf: Apologies, but I do not really understand the question.=3D20

The best explanation available to me is Parmelee's. Who speaks of =3D
viscosity as a "property of fluids" that "controls the thickness =3D
uniformity of the matured glaze" And like that. Parmelee goes on to =3D
explain it all.

I am not at all clear where we go, where you would like [us] to go with =3D

As far as I know the viscosity of a glaze depends on what the potter =3D
wants to achieve. For clear glazes a more fluid melt is wanted than for =
a matt depending on immaturity. But that is no more a revelation than =3D
telling you that for a pudding you want a starch/liquid mix thicker than =
for a sauce, thicker than for a soup....In this cookery example the =3D
balance is between a starch (and there are different starches with =3D
different effects) and a liquid. In glaze the balance is between fluxes =
and alumina/silica. =3D20

There are "Limit formulas" which are educated guesses about what =3D
proportions of flux/alumina/silica will produce the best results at =3D
specific temperatures.

But one must remember that the actual viscosity of a glaze is affected =3D
by several extraneous [?] factors: the clay the glaze is on, the speed =3D
and kind of firing and cooling...

May I ask what you are trying to achieve?


Lili Krakowski
Be of good courage