[Rees Guitars]

Hi guys,
I have a Solsylva 2'x4' rack and pinion router. Bit of backlash in the X axis, so I got to thinking. What if I solidly mount the racks at each end, leaving a little bit of-up and-down slop in the middle, then have a spring tensioned guide wheel on the gantry that pulls the rack tightly toward the pinion?

Has anyone seen this done before? I hope the attached pic explains it well enough.

[mike_Kilroy]

neat concept. all antibacklash r-p systems we have been involved with have been either 2 pinions spring loaded against each other or 2 servos on 2 pinions run in antibacklash mode.

no reason i see it would not work as u show. consideration would be how much spring force required.... seems like it would be quite a bit for a few thousand lbs thrust force. shouldnt be any more wear than ab system like above tho....

[jsheerin]

If you have a constant clearance between the pinion and rack, the rack would have to bend a lot more at the ends. This would require more force which your springs would not provide, so your backlash (or at least preload - the load below which your pinion would stay fully engaged with the rack) would change with position. Why don't you spring load the pinion against the rack as most designs do?