Re: lathe -> cnc

Dave,

From memory, my Accuslide conversion on a Hardinge has 110 oz in
servos. That's with low friction linear ways and precision ball
screws. I've toasted 3 of these motors. IMO, they're too small.
Rapids have to be limited to 300ipm.

For something as heavy (comparatively) as the Jet, I'd think you'd
want to go much bigger. For comparison, my biggest mill has 40 lb in
motors (40 x 16 = 640 oz in.). Even on the mill that's a little
small for large hole drilling.

Just my $.02.

Doug

PS, if you want to go steppers I can get you the name of a guy
running Ahha/steppers on production lathes and swears by them (not at
them).


--- In CAD_CAM_EDM_DRO@egroups.com, dave engvall <dengvall@n...>
wrote:

> Group; (mob) :-)
>
> I have a Jet 1340 which I'm thinking about moving from
> manual to cnc control. At this point my concerns are driving
> the cross-feed (x) and the carriage (z). I think I have the
> axis labeled correctly. ;-)
> Planning on using emc for software. Need guidance in the
> area of servo motors vs. steppers.
>
> Available servo motors:
> a. Hitachi 24 v 2.2 A 38 oz-in with encoder (off DEC
> LA-180 printer.
> b. various 28 V servo motors from 1/2" industrial tape
> drives.
>
> Are these enough power or is more needed? Response times
> adequate for threading are critical!
>
> Germane to the whole issue is whether to go servo, either
> the ones I have or go for more power, or try steppers. (
> Don't want to start any religious wars here but the answers
> will be useful).
>
> Recommendations, experiences, etc. would be appreciated.
>
> Dave