DRO: Newbie Q

Hi Folks,

I've migrated over from the 7x10 mini-lathe eGroup because I'm
designing a DRO for my mini-mill and need some advice. I plan on
using rotary encoders (probably from US Digital) and either PC-based
or PIC-based software, but I'm now trying to figure out the best way
to convert my linear motion to rotary. Here are a couple of the
questions I'm facing:

1) I've seen people using cable and pullies to drive their encoder -
this doesn't seem wise. What's the consensis for the drive mechanism:
rack&pinion or cable (or other?)

2) Assuming I'm using a rack and pinion, it seems tough to find a
combination that gives me more than 1 1/2 rotations per inch. Does
anyone know if the encoders from US Digital (HP I believe) provide
quadrature output so I can quadruple their resolution?

I realize I'm probably re-hashing old conversation but I wasn't able
to find anything in the archives. Please direct me to old threads if
they're out there.

Thanks,

Jeff

http://www.swayze.org/shop/