Lily Krakowski on wed 18 dec 02
There are then, certain basic ingredients we use in glazes, the fluxes or
melting agents, the sticker or aluminum, and the glass former, silica. What
we really are after is silica that stick to the pot--and turns to a kind of
glass at the desired temperature. Or why we add fluxes.
The ingredients we want are available in a great number of materials. This
in turn creates lots and lots of confusion for novices because they think
they have to get each and every material, without realizing that these
materials contain the same very important ingredient. If I want
carbohydrates I can get rice, or pasta, or bread--but I must know AHEAD OF
TIME that this desired ingredient comes in many forms.
Now if a novice asks for recipes s/he is likely to get half a dozen that
are so similar as to make no never mind. I could send in a recipe that
calls for Wollastonite, talc, clay, and Frit X, and someone else a recipe
that calls for whiting, dolomite, flint, and Frit Y, and the novice would
not know they are identical, more or less. Close enough to substitute for
each other.
To ask for recipes for glazes is like asking for recipes for banana bread,
or matzo balls, or stew. One has to know a bit about the materials before
one can analyze how different the recipes are from each other. (I would
never make matzo balls without some nutmeg. Others would not make them
without onion. Neither nutmeg nor onion are really important....they are
flavorings only--just as colorants are in glaze--and do not affect the
actual matzo ball/glaze.)
That is why a novice must get ahold of a book that lists materials, and Frit
analyses which a dealer will supply, or one can get from the Wm Hunt article
in Ceramics Monthly, May 1978. And the novice must learn to do glaze
calculations. There are computer glaze programs, which I know nothing
about, glaze calculations done from the % chemical analyses that come with
the material when it is sent (if not, ask dealer for it) or the good old
molecular formula route explained in most books.
What also is important to know is that the fluxes have an effect on color.
There is no use trying to get a cool blue in a high magnesium glaze, or a
chrome green in a high zinc one.
What is a beginner to do? First go to the Library and find out what books
can be had. Read them and copy out information. You will keep this the
rest of your life. Order some books on glaze and, as I have suggested
before, get them from a place where they know their stuff--either a ceramic
supply house, the bookstore of an art school that teaches clay, or a book
store like The Potters Shop. There is no point--unless you ahve a
recommendation of buying from a bookstore that has no idea about glaze.
Master glaze calculation. This should not take more than two hours. Copy
out some glaze recipes, makes no difference what kind, where from, and turn
them into formulas.
Order a MINIMUM of supplies. MINIMUM means few and little. Now that you
know what is IN these materials, you decide what you plan to use.
Order two or three different clay bodies for the temperature you will be
using, and the kind or work you do. There are numbers of good clay
suppliers and many will send you just one 25 lb lump of several clays to
try. Make test tiles and bisque them.
You now are ready to ask for glaze recipes. I would suggest you sort them
out: calcium borate ones, zinc containing ones, soda and potash and lithium
ones, magnesium ones. You want a transparent, and maybe three opaque glazes
with different fluxes so you can test colors.
And then you start testing on the different bodies to see what you like the
best.
Lili Krakowski
P.O. Box #1
Constableville, N.Y.
(315) 942-5916/ 397-2389
Be of good courage....
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