I know little about heat treating, but from what I do know about the
temp ranges involved I think a type K thermocouple would be suitable.
Type K is good up to about 2000 deg F, maybe a bit higher, most
controllers I've seen accomodate type K and they're readily available.

You can get type K thermocouple wire from McMaster, along with the
yellow connectors for them. It's easy to weld up thermocouples from
wire, and it's a lot cheaper than buying them readymade if you don't
need 0.1 degree absolute accuracy.

I weld "utility" thermocouples with a Smith O/A Li'l Torch. If I want
them better than that, I TIG weld them! I pull an arc with the TIG
to a copper block and then bring the wires near the arc (and within
the argon shielding gas) to weld them. It works for me!

On Tue, 31 Aug 2004 21:30:46 -0400, "John Wilson"
wrote:

I have a small 6"x6"x4" oven and need temperature control.

I am considering a Fuji PXR3 temperature/process controller and will need a
thermocouple and a power switching device.

My electronic skills are pretty basic. I would welcome advice on what
thermocouple, insulation and housing is best suited.

Should I choose a relay or a sold state relay?

Is there a better way to heat treat and case harden?

TIA, John.