Parts were all .065" tube, VERY fast to come up to heat. You get charged
for the furnace time, this was a fast job.

The other Thomas Gardner wrote:
This is excellent info. Thanks.

RoyJ wrote:

[...]
The other shops were high volume production places. We also did one job
that had 16 4130 frames mounted in a rack that went into a 8' diameter
by 16' deep pit furnace. 3 pits in a row, (high temp, quench, temper)
with an overhead crane. $500 for the lot.


That'll probably be close to my situation, I believe. Having a hard
time picturing the volume, though. You recall approximate thicknesses
on your parts? What kind of tonnage would you guess on that?


[...]
I'm sure that you can get some competitive bids once you get to 100 at a
time.


That's exactly what I'm hoping for.


I'd toss out a SWAG number but you really didn't give enough
detail on the part.


Well, a 3.5" per side cube is pretty much it. Of course it's got
dovetails cut on 2 faces (this is a QC lathe toolpost). There are some
other bits taken out hither and yon, but mostly, it's really pretty
close to a solid cube. If you'd care to SWAG that, you *SURE* wouldn't
hear complaints from me. :-)


Keep in mind that if your "cube" is anyere near solid (eg a block with a
few holes drilled in it), heat treating gets real fussy. It takes a
longer time to get the whole part up to temp, quenching evenly is
difficult. And then there is the warpage and shrinkage problems.


Yeah, well, I assume I'll have to do some grinding when it comes back.
Another reason why I was (and really, still am) hoping to pick a
material that would be wear resistant enough for the job even without
heat-treatment.

I've been reading like crazy trying to educate myself, and somehow or
another, I seem to have gotten the impression that warpage and shrinkage
problems are worse, the faster the quench process required for the
material. So, for instance, a water quench will warp parts far worse
than an oil quench. Is that true? If so, what about something that can
be air hardened? Wouldn't that be slower still, and therefore deform
parts even less? Of course, I also seem to recall that big honking thick
parts like the ones I'm talking about, would have to be oil quenched,
even with air hardening materials chosen (part just won't cool down fast
enough in air if it's too thick). Is that something I just imagined?


If you
just call up a volume place and dont have ready answers about what
tolerances you can live with, they will give you the run around.


Exactly! Trying to find my clue now. I'd rather find it in a newsgroup
than with a dealer where it could cost me oh, so dearly, in oh, so many
ways.

Thank you so much for your help. I do appreciate it.