On Sat, 7 Feb 2004 10:25:04 -0600, "Tim Williams" wrote:
"Harold & Susan Vordos" wrote in message
...
What I would be really impressed by is a homemade neutral atmosphere
furnace !!!

Absolutely, or a controlled atmosphere one (same thing?). If you've seen
parts that have come from such a furnace, it puts things right in
perspective.

I bet you could do by first sealing the outside box very well (welded seams
I guess), making very certain of the leakage points (i.e. door), then
filling it with a few CFM of natural gas (as you say), or propane since
Roy's a gas nut, which could be applied with something like a torch.

That'd give you a carburizing atmosphere, perhaps useful for case
hardening, but more likely to produce a large BOOM if any air remains
in the furnace.

Maybe one using compressed air as well so you can completely turn off the
gas and get an oxidizing/well-ventilated atmosphere (say if you wanted to do
pottery? err I mean make your own crucibles .

Not much use for an oxidizing atmosphere in a heat treating furnace.
You'd get *lots* of scale, decarburization of the steel, etc.

Or even hook it up to your MIG bottle and get a completely inert
atmosphere... not sure what would need that though.

Now you're talking. An inert atmosphere will prevent either carburization
or oxidation of the steel. The part will come out nice and bright and clean
with exactly the chemical composition it had when it went in, but with a
different grain structure due to the heat treating. That's exactly what
you want.

Gary