On Tue, 26 Sep 2017 09:18:37 -0700 (PDT), "
wrote:

On Tuesday, September 26, 2017 at 11:54:32 AM UTC-4, wrote:

Any thing is better than nothing. Your hydraulic oil is not going to be the best possible, but will probably be about 90 % of the best possible oil/coolant.

Dan
Actually Dan, hydraulic oil makes lousy cutting oil, not even close to
being 90% as good as the best possible cutting oils or coolants.

Eric

Thanks for the correction. For years I have used what ever is handy including ATF. And believed it was much better than nothing.

Dan
Maybe better than nothing, but certainly not as near as good as
cutting oil. Have you tried bacon fat? Even bacon fat is better than
motor oil. Seriously.
Eric