Lily Krakowski on thu 7 aug 03
Not necessarily so.
If your glazes are made of SAFE ingredients, to the best of my knowledge no
combo makes them unsafe.
But the blending of two glazes essentially takes the ingredients back to
square one. And there is something I consider purely miraculous, and do not
really understand, but Ron or Ivor or Tom or John plus a few more do--called
EUTECTIC. And that may happen, and then the glaze will flux at a lower
temp than either one alone.
So if you do it, do it carefully, on a test tile, with a "cookie" (a little
pancake of bisqued clay) underneath.
Lili Krakowski
P.O. Box #1
Constableville, N.Y.
(315) 942-5916/ 397-2389
Be of good courage....
iandol on fri 8 aug 03
Dear Lily Krakowski,
As Prof Joad would say, 'It all depends on what you mean...' when you =
say "Eutectic".
There is no doubt the probabilities are that if one of the recipes had =
been prefused to create a frit and then mixed with the other the =
combination will have a lower fusion point.
In addition, if the combination of both recipes caused an imbalance, a =
departure from recognised norms of one or more substances, there might =
be a degree of instability or reduced durability introduced into the =
system. For example, if both were rich in Sodium compounds you might =
induce crazing. Or there might be other synergistic reactions affecting =
viscosity or surface tension.
I think the original question is best answered by suggesting that the =
idea be tested, as someone has already pointed out. People should not be =
fearful about doing these things for themselves. Self experience is a =
good and beneficial thing.....
Today, I found out that Frit 3134, fired to cone six, gives a milky well =
fused glossy surface but 20% Whiting makes the frit fuse to a =
transparent coating but induces crazing and less gloss. 30%whiting leads =
to the precipitation of microscopic crystals. Now I could have asked the =
Gurus to tell me what would happen if I fired whiting with Frit. But =
rather than impose on them I did the trial.
Best regards,
Ivor Lewis. Redhill, South Australia.
Best regards,=20
Ivor Lewis. Redhill, South Australia.
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