motor sizing

I'm building a 60"x60"x6" light duty cnc router table. I'll be using
thompson linear rails and bearings, the y axis should weigh around
45lb.

The linear actuators I've bought produce 45lb max linear thrust. They
are nema 23, draw 1.5 amps, probably 65-100oz/in of torque, with a
leadscrew going through the center of the motor, with 16 turns per
inch, giving 3200 steps per inch.

Are these motors to light weight for this application? Or, will they
work, but just not as fast as higher powered motors would?

From what I've read on the 'Net, these seem to be in the ballpark.
Any practical experience any of you want to share?

Richard Spelling, http://www.spellingbusiness.com/boats
From the muddy waters of Oklahoma