In article
,
Jim Wilkins wrote:

I'm milling the semicircular radius on sheet metal brake hinges on a
rotary table. Milling the steel dry is giving me a better finish than
a little oil does as long as I hold a brush on the back side of the
end mill to remove adhering slivers.

I've had the same experience with brushed oil. The problem is that the
oil keeps the chips in the action. A mister with enough airflow to blow
the chips away yields a considerable improvement, as does copious flood
cooling.

Joe Gwinn