Bill Merrill on sat 30 jan 10
PART 2 FLAMEWARE
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It is very important to use the right type of spodumene. The best
spodumene is mined by Foote Mineral at Kings Mt., North Carolina. For
information on its chemical analysis and cost write:=3D20
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Foote Mineral Company
Route 100
Exton, Pa, 19341
(215) 363-6500=3D20
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It is the lowest in iron and highest in alumina content that I have
tested. Lithium Corporation of America, Box 795, Bessemer City, North
Carolina 28016, also produces spodumene, but it is very high in iron
content, which I found unacceptable. The problem of iron content is very
hard to overcome due to the fact that the iron is chemically combined in
the crystal. This makes useless the removal of iron by the magnetic
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Foote Mineral is now producing a low-iron spodumene for the glass
industry, but it is not ground in mesh sizes for use in a clay body.
This low iron spodumene would enable one to produce a light
gray-to-white clay body. (The fired color of my flameware body is
orange-to-deep-red-brown.) They are also producing a calcined spodumene
which I feel has great potential in lower temperature flameware bodies.=3D2=
0
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The pyrophyllite used is called Pyrotrol 200 mesh, and comes from:=3D20
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Piedmont Minerals Company
PO Box 7247
Greensboro, North Carolina 27407
(919) 292-0947=3D20
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I used Kona A3 feldspar in the flameware body up until it was
discontinued. Since that time we have been using K-200, a feldspar mined
by the Feldspar Corporation of America, Kings Mt., North Carolina. I
have found it to be an excellent substitute. The body seals up a little
more, but I have found no adverse conditions in the flameproof
qualities.=3D20
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My reason for using Old Mine #4 ball clay is for its color. It is very
light-burning and is as plastic as any ball clay I have ever used. I
feel sure any ball clay would work as well.=3D20
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The fire clay is dry-milled A.P. Green fireclay. It seems to be plastic
enough, and I am interested in its large particle size, which I feel is
important in this flameware body. We have used other plastic fireclays,
but I found them unacceptable in the fired results. The clay body seals
up more than necessary and the clay body lacks the terracotta appearance
which it normally has.=3D20
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No matter what clay formula you might come up with, the word MACALOID is
an essential. Macaloid is a chemically-combined Hector Clay, used in
industry as a suspension agent in lotions. In a clay body it is the
greatest little plasticizer I have ever used. Because the flameware body
has too little clay, some type of super-plastic material is essential to
make it workable. Macaloid is the answer.=3D20
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Macaloid is produced by National Lead Company. For information write:=3D20
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TAM Division
Box C, Bridge Station
Niagara Falls, NY, 14305=3D20
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It is also being sold by some major ceramic suppliers. It is a very
expensive material, but worth every penny.=3D20
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You must remember that the information in this article is only a staging
point for anyone becoming interested in flameware. I use this formula
because it has been most serviceable for me. I feel sure that
innumerable clay bodies can be developed from this basic formula. For
instance, if the clays used are more refractory, use more flux; if the
opposite, decrease the flux.=3D20
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It is important to realize that the glaze used on flameware is as
important as the body. My experience shows that glazes with 15 to 25 per
cent spodumene or lepidolite will generally work well on flameware. Many
other glazes, especially high alumina glazes, will also work. Here are
some basic formulae:=3D20
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#1 Flameware Glaze c/9-10
(White with red flecks)=3D20
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Lepidolite
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32
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Dolomite
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25
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Whiting
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3
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Talc
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3
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Gerstley Borate
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2.5
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Kaolin
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25
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Flint
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9.5
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#2 Flameware Glaze c/9-10
(Orange to white)=3D20
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Potash Feldspar
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6
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Spodumene
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4
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Dolomite
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4.5
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Kaolin
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5
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Whiting
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0.75
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Tin Oxide
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1
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Addition of 2% Cobalt Carbonate gives a nice blue.=3D20
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#3 Flameware Glaze c/9-10
(Brown to green)=3D20
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Dolomite
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12.4
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Whiting
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1.6
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Potash Feldspar
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10
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Kaolin
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12.8
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Flint
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2.8
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Cobalt Carbonate
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0.2
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Red Iron Oxide
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0.4
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Any glaze you use will change its image on flameware due to the large
amount of flux in the body. This will make most glazes more fluid, and
tones out most colors. I enjoy color in my glazes, which leads me to
fire flameware at just about cone 9 or 9 1/2. This allows the glazes to
be less fluid and does not burn the color away. My glaze firings,
moreover, are reduced very little due to the fact that we found the
carbon deposits under the glaze to be damaging. They will cause the
glaze to begin popping off the surface of the ware after several months
of use.=3D20
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During firing any protruding parts, such as skillet handles, must be
supported. The body becomes so fluid during the end of the firing that
it is capable of oblonging itself, Those handles which are light-weight
will need no support.=3D20
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I hope these remarks will enable you to make a start with flameware.
They come from my own personai experience, and while I am not a trained
technician, flameware has been an interest of mine for a number of
years. A great deal of help was given by Foote Mineral Company and the
Lithium Corporation of America. If you have an interest in lithium
compounds, these people are more than willing to help and supply
samples.=3D20
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