Im LOSING steps?!

Hey all, i'm calibrating my steps per on my mill and having a very hard time with my y axis. It's on ballscrews and linear rails and very smooth so binding isn't the issue. When i try to and step to my gage block to touch with the indicator sometimes it will move a true .010 and other times the motor wines just ever so slightly and will on move a few thou. As you know this will make it near impossible to calibrate.I'm stumped. I did my x and z perfectly. I got them with in .0001 on each axis. But the Y is being a b***h.

Any suggestions? I'm using mach3 by the way.

PS I tried turning down the Acceleration but still the same result.


Thanks.

I'd probably mess with the acceleration some more. Although it's counter intuitive it's possible increasing the acceleration will help.

Does the motor act the same way at any part of the table?
- sorry, I know you already said binding isn't an issue, I just figured I'd ask this anyway in case it helps.

Maybe something is wrong with that driver?
Try hooking the Y to another driver - does the problem go away?
and/or
Hook the Y driver to another axis - does the problem appear on the other axis?

Hi, You're saying that when you touch the Z axis with your finger, it drops a little, right?
What kind of steppers are you using? It can be low torque problem I guess. If torque isn't the problem, maybe there's lacking (or missing ajustment)power, what kind of eletronics are you using?
Anyway, this can be fixed with some springs
(the springs ideia can be hard to accept at first, but they're very funcional and sometimes common as a compensation system helping lifting.)

no the problem is the Y axis not the Z. Keling motors, Gecko G540, 48v PS nothing crazy

Hoss has some good videos on calibration. Check out hossmachine.info