Joe's recent thread about his dribble cooling for his lathe reminds me
of questions that I have.

1. What is the purpose of cooling? Does the tool get so hot without it
that the edge is dulled? I thought HSS & especially carbide could stand
the temperatures created by HSM work.

2. What is the purpose of cutting oil? I remember reading that it
allowed chips to flow off the cutting edge more easily. Is that it?

3. Does choice of cooling or lube depend upon the tool (lathe, mill,
drill press, band saw), or material? Or both? I'd like to fill in the
chart (my guesses shown):

Mild Cast Tool*
Steel Iron Steel Alum Brass

Lathe ? D ? ? D

Mill ? D ? ? D

Drill ? D ? K D
press

Band W D ? ? D
saw

C = coolant
L = lube
D = dry
K = kerosene or equiv
W = wax

* - actually I don't care about Tool Steel, as I never use it. It's
included for completeness

Thanks,
Bob