This whole subject needs a good venting here. Over the years I've seen an
endless stream of misconceptions about coolants and lubricants, and, of
course, we have a wide range of hobbyists and commercial shops represented
here, using many different types and vintages of machines. Most of us
hobbyists, running 60-year-old toolroom-type lathes and HSS tools, have no
business running coolant of any kind. We should be using cutting oils, not
soluble oils or synthetics. And, except for people using better production
machines of more recent vintage, few of us run carbide at its limits,
either, and have little or no need for coolants. Coolants come into


OK, educate me. I am using a series one Bridgeport mill and a 70s Graziano
lathe. I mostly use carbide indexable cutting tools, but some solid carbide
and HSS mills. What lubricants (available in California) would be best for
steel and titanium? I am with happy with kerosene for aluminum , and cut
magnesium dry.
I generally keep my speeds and feeds to the low side to reduce tool costs,
and avoid blue chips. Should I let the work get really hot, and then have to
figure shrinkage into the final dimension?