I received the Xylotex drive box recently and just became curious. The motors are double shafted, so would it be hard to attach an optical encoder to one side and make the system closed loop?
If there was software available to do it, without spending a LOT of money, that's all you'd have to do. You can by an encoder board that works with Mach3 that will pause your machine if it loses steps. Not fully closed loop, but partially. www.rogersmachine.net
Gerry
Mach3 2010 Screenset
http://home.comcast.net/~cncwoodworker/2010.html
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)