On Thu, 31 Jul 2008 12:56:31 -0700 (PDT), "Denis G."
wrote:

Sometime recently I read about someone who acquired an older milling
machine that had hydraulic feed on the table. I wondered about how
these tables might be controlled and if any lathes have been designed
using hydraulics to move the carriage or crossfeed instead of lead or
feedscrews.

Hydraulic duplicating (tracer) mills and lathes were once common. Last
I knew a customer of mine was still using a tracer mill to duplicate
molds for shoe counters for which there was no CAD data available.
Google True-Trace or Mimik and you may find some info.

Sinker EDM rams were often servo-hydraulic, but, I think, not so much
for coordinated motion as for smooth motion at very slow speeds

All the large planers I've seen were hydraulically driven, though
that's more for brute force rather than controlled motion.

--
Ned Simmons