I'm in the final stages of finalising my "deep router" design and am pondering on the wisdom of using one-sided drive for the X axis. The machine working area is ~800mm x ~600mm, with the Y axis having two widely (~200mm) spaced beams that carry supported rails. The X axis rails are also fully supported and sit on top of tall side members, rather like the Mechmate designs.

I've spotted this design: http://www.durhamrobotics.com/easypage_2.html and have been giving some thought to the idea of only driving one side. I believe that I can make the "gantry" stiff enough, by having the Y rail support beams widely spaced and very well braced, for the light work I envisage this machine will be doing (mainly foam carving and a bit of woodwork, perhaps, but most probably only softwoods/MDF).

I used to have an A3 plotter that was only driven on one side and it seemed top work fine, but obviously the loads were very small. For this machine I'm using fully supported 16mm rails and linear bearings, so should be able to keep friction, and stiction, reasonably low.

Has anyone got any experience of one-sided drive machines please?

Jeremy