Lili Krakowski on tue 13 dec 05
Nancy Hughes wants a zinc-less clear, and has a recipe for a clear matt =
cone 4-7=20
=20
Ferro frit 4508 ...50%
Potash feldspar...20%
Ball clay...20% =20
mag carb...10%=20
I looked at the lengthy chart Wm Hunt published of frits and their =
ingredients and that number does not appear. I checked not only Ferro, =
but Hommell and Pemco, thinking maybe the name of the manufacturer had =
been wrong.
Sorry. Nothing by that number. You might consider writing Ferro.
I wonder: might Ferro use different numbers in other countries...? =
What is the source of that recipe? Just curious.
As to a clear glaze without zinc. I have been using my BB Clear =
forever, and it works very well on the bodies I use at c. 6.
Frit 3124 67.6
OM4 ball clay 7
Silica 23.2
Bentonite 2.1
And a little calcium chloride or Epsom salts to make it pour nicely.=20
You might consider testing your totally favorite OPACIFIED white glaze =
without opacifier...that often works splendidly.=20
Now: as to Heloisa's question about Calcium Borate Frits.
Several British writers use that designation to cover the range of =
calcium plus boron containing frits.=20
As she mentions she is trying a Bailey recipe, I looked at the back of =
his book. There he lists several calcium borates. Colemanite and =
Gerstely Borate (natural products as it were, though I gather mostly =
blends nowadays [?] Ferro Frit 3124, BPS calcium borate, Potclays P2268, =
Potterycrafts P 2954.
So, Heloisa, remember the Brazilian proverb: who does not have a dog, =
hunts with a cat, and get what you can, and test.
Lili Krakowski
Be of good courage
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