On Wed, 14 Oct 2015 15:59:35 -0500, Tim Wescott
wrote:

Just a quick question because I know it works:

Last night I needed to make a couple of chinguses (ding-wazzles?) out of
O-2, and since I haven't actually hardened any O-2 ever, I didn't have
any ATF handy. But I did have some power steering fluid, so I used
that. It appears to have worked fine (particularly because the
specification I'm working to is "hard", without any, like, numbers).

Any reason not to? Or for the purposes of plunging hot bits of metal
into, are they essentially the same thing?

The way I understand it, oil is slower to boil than water so it
quickens the time the part quenches. PS fluid is a bit thinner than
most oils, so it would be a slightly slower-hardening liquid, but pert
much same-same. Still quite a bit different from water, so the O-2
hardening should be "safe" and proper.

--
Stay centered by accepting whatever you are doing.
This is the ultimate. -- Chuang-tzu