Y axis lost postions

I am lost at this point. Tried everything i can think of.

I will set my XYZ zero’s and run my first program. Next, after a tool change. I will run my second operation. However, my Y position is always off my +.03 - .070", every time.

I removed G28 from my programs so the machine does not home, hoping it was a limit switch issue, but it still happens.

Currently i am unable to use my machine without probing Y at every tool change. X and Z are fine.

Any help would be appreciated.

Sounds like you’re losing steps. Something is in a bind, too tight, or you’re taking off too much material at once.


I am cutting .020" deep into soft plastic.

Just figured out it is the boring tool path. Removed it and the problem went away. It is very odd though, it will even lose steps when cutting 1" above the part too. Doesnt even start the hole at the correct position.

After a while my machine settled and had a slight bit of twist in it. It had dropped maybe 0.15" in the right rear and nearly as much in the left front. Can’t remember the angle it was putting into the table but I want to say 1.6 degrees sounds about right. It was putting the Y axis in a bind about half way through its travel. Could have been the adjustable feet settling, or the whole assembly.

After getting it level again I went back through the steps of loosening the X axis gantry, broke the Y axis bolts loose and jogged the Y axis back and forth a few times to let the rails align, then tightened the Y axis bolts down while Y was about mid travel. Resquared the X axis and it took care of the missed steps.
May not be your issue here, but something to think about.

Thanks, I will try this.