I.Lewis on thu 13 jan 00
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Carolyn Nygren Curran asks some intriguing questions about supports for high
fired ornaments.
My understanding is that Kanthal metal will resist high temperatures and has=
the
resistance characteristics which make it a good material for converting
electricity into heat. But it does not have the bulk strength at those
temperatures to support itself. So if a load is imposed on it will sag.
My own experience is that steel fencing wire, which has a melting point well
above cone 12, is useful, though not ideal because it throws a lot of oxide =
and
it will bend if there is a heavy load. Fourteen gauge, fairly stout stuff, =
which
can be cut with electricians pliers, will do the job at a pinch. It is cheap
enough to discard after each firing. Perhaps this magic ITC stuff would help=
to
prevent the oxidation problem.
However, I think there is a much better answer. There are some excellent =
Cobalt
alloys which resist high temperature environments. They are available as =
smooth
rods about eighteen inches long and one eighth of an inch round and cost =
about
Four Aussie Dollars each. Those who might wish to try this idea out should =
ask
for STELLITE 1, 3.2mm Bare Hardsurfacing Rods. The composition is Carbon =
2.5,
Chromium 30, Tungsten 12, balance Cobalt.
Address in USA Thermodyne Stoody, 5557 Nashville Road, Bowling Green, NY =
42101
Address in Canada. Deloro Stellite Inc, PO box 5300, Belville, Ontario K8N =
5C4
Address in United Kingdom. Deloro Stellite Limited, Stratton Saint Margaret,
Swindon, Wiltshire SN3 4QA, England.
Address in Australia. Local Commonwealth Industrial Gas Agent in Capital =
cities
and major towns.
I could say a lot more about this type of alloy but for the time being just
accept that it has good high temperature strength and resists oxidation.
Hope that helps out,
Ivor Lewis
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