[gurvy]

Using Mach 3 my Z axis drops over time, I have read a million posts and tried a million different software settings to no avail. Does Anyone know of a setting in Mach to set an incremental step increase in one direction? say for every step one direction use 1.1 steps the other direction to compensate for hardware slippage or better yet for every direction change add 1 step. Everything I read applies to motion correcting both directions and not just one way.

[ger21]

Try lowering your accel and velocity settings by half and see if it helps.

[gurvy]

I have tried this method many many times. The more often my z changes direction the more it drops. I would love to simply add a command to mach3 somewhere to simply say add +0.001 every direction change on Z
Thanks for your reply though.

[TOTALLYRC]

I think you are trying to fix the wrong problem. Fix the problem that is causing you to loose steps/Z to drop. As wonderful as the software is there is not a substitute for decent hardware.

[TOTALLYRC]

By the way if you post some more inofrmation we can probablly help. Such as motor type, voltage, driver, and the like. If the hardware is truly slipping, you will need to fix the hardware. Over what period of time/ number of cycles are you losing steps/Z dropping?

[mc-motorsports]

are you having problems with backlash? I only enable the backlash when making precision parts, never for high speed ballmilling operations. I think my X is set to .001, y is set to .0015 and z is set to .0012", this compensates for slop or streach in the drive belts and error in the ball screws/ball nut.
Did that answer your question?

[mc-motorsports]

sorry the pics are so small, maybe save them and zoom in using paint or photoshop. But it will show you how to get to the backlash settings if that was the problem.

[mc-motorsports]

I'm sorry, I just re-read the post and I realize your losing steps. Not the cheapest fix, but maybe the best, use a servo with encoder feedback with a Gecko driver(or similar, I'm just partial to Gecko) for your Z, mine is deadly accurate even over an 8 hour cycle time.