stepper stalls out

[edgara]

EMF problems. Buiilt a wood router 3 axis cnc. Bipolar 2 phase 4 wire steppers Added dampers to x an y. Same hardware used on all 3 axis. Motors tuned the same on x an y, however, x runs smoothly after damper was installed, y does not. If I plug x control wiring into motor y, it runs as smooth and fast as y. When I reconnect the y control lines y stalls out. Both have the same motor and individual power source and controller. Does y have a screwed up controller or emf problem or both? I can drop y ipm to make it run. I was thinking of adding some fast recovery diodes, but I don't know how or where to wire them in. Any help would be appreciated.
Thanks all

[Dorsal]

It sounds to me like Y has some misalignment on your linear slides and the problem is purely physical.
Or maybe you need to orient your machine so the Earth's magnetic field is properly oriented to the magnetics of the steppers.
Have you tried adjusting the VFD for that axis, to reduce the harmonics?
Have you tried sliding that axis around with the stepper disconnected, to sample the tight spots?
Would you like to get some suggestions that were remotely related to your setup?
Tell us what steppers, what controller board, what power supply, what software, if you've used a voltmeter to check or you're just guessing, WHAT you're working with, please.

[edgara]

Thanks for the reply. My lead screws are 8tpi, and are freewheeling by hand, I have nema 34 mtrs (1316oz),with SD-2H086MB drv.,3 3-100-24 ps. I believe I already mentioned I took the x axis connection and hooked it to the problem y axis and the axis ran great.I'm running mach 3. I've checked power supplies with volt meter all are consistent 24v. all axis are wired the same. All wire is 2 strand shielded 20 guage. Today I disconected all electronics except the problem mtr and ps and controller (to eliminate all possibilty of interference). Mtr still stalled out. Since I can hook the wiring from a different axis and the mtr performs great, I don't think it could be magnetic interference. I might have 1 bad controller, next chance I get I'll try the questionable controler on a different mtr and see how it performs. I am open to all sugesstions , if you want more info just ask, thanks