DIYbanter - Can I use a TIG welder to melt metal in small crucibles?

Absolutely. Later in the thread you say you have 100% duty cycle, and later
still you mention 200 amperes. At a typical arc voltage of say 30V, that's
a good 6kW burning away the argon. (Which BTW is slightly heavier than air;
argon heated to 5000°F however isn't! ;-)

Figure 1kW per pound of steel in a reasonable furnace. You'll need a layer
of high-temp kaowool or fiberfrax or whatever to insulate it good, then a
hard refractory hearth to melt the steel in; a small crucible wouldn't hurt,
but mind if it comes with a protective glaze that'll eat the hell out of the
kaowool! The arc obviously has to be enclosed to save heat (your greatest
loss at lightbulb temperatures here is radiation, and there's about 6kW of
it...), so you'll need another hardened hemisphere enclosing the deal with
no gaps for light (heat) to get through.

Two carbon gouging rods will certainly work well here (at 200A, you'll
probably want 3/8 to 1/2" dia. rods). You can draw one or two arcs off the
metal to each electrode, or use an indirect arc above the melt. Figure a
half hour melt time and remember to adjust the electrodes, as they will
vaporize! Get good clamps, too- nothing worse than melting the electrodes
off the wires!

Speaking of electrodes, they'll give a reducing atmosphere of CO and carbon
vapor in nitrogen, so argon isn't really required.

Tim

--
Deep Fryer: a very philosophical monk.
Website: http://webpages.charter.net/dawill/tmoranwms

"Ignoramus29878" wrote in message
...
The subject says it all. I wonder if I can use a tig torch to melt
metal in little (or not so little) crucibles. With at least 5kW at the
arc, I could melt pretty big stuff.

i