Drives and Power supplies

I was wondering if anyone could offer comments on the tradeoffs
between the Gecko G210 and Dan Mauch's 5 amp chopper kit for driving
470 oz/in or so steppers.

I know the basics: The Gecko is slightly less than twice the price of
Dan's kit, and has a nifty microstepping multiplier.

How usefull is microstepping on a basic lathe conversion that would
not need particularly high speeds and already has some timing belt
reduction in the crossfeed?

Any ideas as to which unit is more robust/fixable?

Also, on power supplies, I found some unregulated linear supplies
designed to put +/- 50v into ancient bipolar servo amps (no docs for
those, alas). They seem to be capable of at least 5 amps at 100v.
The secondary has 2 center tapped windings labeled 34vac each, and
uses a single bridge rectifier for the +/- supply with a cap on each
side.

Am I right in thinking that I could parallel the windings and caps,
move the ground connection, and get a 50v supply?

Or could I leave the windings in series but move one wire to the
center tap for about 75v? I guess I'd have to leave the caps in
series then, as they are only rated for 75v, but I'd still have
17,000uf/2 = 8500uf.

thanks,

Chris

--
Christopher C. Stratton, stratton@...
Instrument Maker, Horn Player & Engineer
22 Adrian Street, Somerville, MA 02143
http://www.mdc.net/~stratton
NEW PHONE NUMBER: (617) 628-1062 home, 253-2606 MIT