Re: Lathe x vrs. z feed rates
hy i also looked into this a while ago, trying to figure out the time needed to cut a face with g96; i just run a few trials to figure out if feed is full or halved, etc
things may change for y lathes
as for roughness, once you do the math, in reality you could go faster, because, if you use the calculated feed, then real roughness will be way better than expected; thus you can obtain a desired roughness at a feed > estimation, because, in reality, some plastic deformation occurs during turning, that will smooth out the surface. If you have an inhouse rugozimeter, then adjust as you go / kindly
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