I finally figured out why my tool offsets kept drifting on the VF-2
Ran a job last week on a Haas VF-2, some aluminum brackets, nothing crazy. But every 20 parts or so I'd check the first piece and find the Z was off by like 0.003. Drove me nuts. I cleaned the tool holders, checked the drawbar force, all that stuff. Then I noticed it was always after I used the 3/8 end mill, never the other tools. Turns out the collet nut on that holder was cracked. Not bad enough to see without really looking, but it was letting the tool slip under heavy cuts. Found a tiny hairline fracture along the thread. Swapped to a new holder and ran 100 parts without touching the offset. Has anyone else had a collet nut that looked fine but was actually wrecked?