Spent 6 hours chasing a Z-axis drift on a Haas VF-2

Ran into a Z-axis drift on our 2018 Haas VF-2 this week. Thought it was a loose coupling but turned out the thrust bearing had a tiny flat spot from a crash the previous operator never reported. Took me 6 hours of pulling covers and checking parameters to finally find it. Has anyone else had a hidden crash damage issue pop up way later like that?

2 comments

2 Comments

the_mia18h ago

Did you check if the crash might've bent the ball screw nut housing just enough to cause preload issues? That kind of tiny deformation is easy to miss but shows up as drift over time. Could be worth pulling the nut and checking runout on the screw itself before you button it all back up.

wyattbennett16h ago

Yeah @the_mia, my old Shapeoko did that after a bad crash. Took me forever to figure it out too.