As you can see in video my XXL started doing this when starting a new job.
I was cutting normally, then i changed tool…then this… i’ve checked the Z limit switch…i’ve checked the Z belt…everything is fine…i went back to the previous tool…and it still happen!! any ideas?
If that is the homing than check the homing switch.
If it is when the program starts reset/check z-zero. It looks like the machine is moving to the clearance set above the work-piece before it moves to the program start point. If you share the program I can review and test on virtual machine.