Quick education for experimenter?

I'm looking to skip all the research and get right to a project, so I'd like some suggestions for direction ;-)
I'd like to build a small (24"x24" or so) XY positioner to drive an oxyacetylene
cutting torch. I can come up with the mechanical part, probably using threaded rod as worm screws.
The torch weighs a few pounds at most, and needs to travel at between 5 and 25 inches per minute. Repeatability isn't too important, as welds can easily correct 1/8" misfits on parts. If I used 5/8x11 allthread rods, that would be between 50 and 250 rpm on the motors.
I haven't physically seen commercial versions of these things, but they apparently use servo motors. Is there a reason to chose servo over stepper? Steppers seem a little simpler to drive.
I'm not very familiar with either type, but I'm a pretty quick study if someone can point me the right direction. I expect to drive the motor drivers with a laptop, probably thru the parallel port, generating the individual step commands. Building a wirewrap driver board with 5804B chips or something is no sweat. Cutting non-linear shapes is desired
I'd like to build this for practically nothing (as much as for the challenge as because I'm cheap).
If someone can ballpark a motor size/torque, etc. from zero information, it would be great and much appreciated!
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You might also want to post this at alt.machines.cnc Those folks seem to do this stuff more regularly.
Michael
like some

oxyacetylene cutting

rod as worm

and 25 inches per

1/8" misfits on

rpm on the

apparently use

seem a little

someone can point

laptop, probably thru

wirewrap driver

shapes is desired

challenge as because

it would be great

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I'd like some

oxyacetylene cutting

threaded rod as worm

5 and 25 inches per

correct 1/8" misfits on

250 rpm on the

they apparently use

Steppers seem a little

if someone can point

laptop, probably thru

a wirewrap driver

shapes is desired

challenge as because

information, it would be great

There was an article in Wooden Boat magazine a few years ago, it might have been a product review, but I don't have those issues handy to search. It was either a 60"x60" or 72"x72" table. Looking at http://www.woodenboat.com/wbbacki.htm , it may be issue #151. There also used to be an ad in the electronic hobbyist magazines, and that may have been closer to your size.
Mike
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