Greetings,

A friend and I are building a heat treating oven for his knife making hobby
and my general home machine shop. He wants to be able to test the hardness
of his knife before and after heat treating (C50-C55 range) and I am
interested in being able to test metal in general (anneal, machine, reharden
to Cxx various sized items that may surface to be worked on) so we are
looking at buying some kind of harness tester. I see lots of larger Wilson
and similar models on ebay but there are many different models (3JR, 1JS,
3JS, 5JR, 12A, and huge variations on prices. Most come with weights and
some come with diamond and different sized ball indenters, which I assume
are all changeable for A/B/C scales. I haven't run one of these machines
before, and while the idea of various weights vs. various sizes of
penetrators makes sense, I'm assuming the plug in cord and remarks of motors
may be to raise and lower the penetrator gently onto/into the test surface.

I also see some smaller portable models, but I have no idea on whether they
would work well enough to be worth buying.

My question is this: does anyone have any comments on specific makes/models
which would do what we want, or anything I should be looking for (or looking
out for) when buying a used tester? Thanks.

Al MacDonald