"Bob Engelhardt" wrote in message
...
If I'm doing rough cuts on a lathe, where the finish is totally
immaterial, is there a difference if I take a .010 cut with .050 feed
versus a .050 cut and .010 feed? I figure in both cases the cross section
of the chip is the same (.010 x .050), so the rate of removal is the same
(for the same speed).


Some thoughts that come to mind.

You may have trouble controlling a machined with the heavier
feedrate/smaller DOC. The carriage will be moving faster.

Secondly, the feed is typically heavily dependant on the nose radius of the
toolbit. Now, you mentioned that the finish is immaterial but if your IPR is
higher than your nose rad, theoretically you'd end up with significant
scalloping. This may make a single finishing pass nearly impossible.

The obvious correction is a larger nose rad. It occurred to me that having
the shortest length of cut along the toolbit's edge reduces horsepower and
rigidity requirements (smaller rad), but that may be a figure of my
imagination. Indeed, if this was the case, the low DOC/high feed combination
would be ideal. Shows how much I know...

Regards,

Robin