Z-Axis Slipping - Bearing needs to be replaced?


I am running a tool-path that requires a lot of z axis movement and I am starting to get slipping while it is moving upwards (I hear a quick grinding noise and the router stops moving). I am not sure if the grinding is from the band slipping on the pulley (sounds too loud for that) or if something else is slipping like the lead screw. All of this is causing the machine to lose tracking on its position (it thinks it went up so many inches but in reality it did not).

I did notice that the flange bearing in the motor plate does not seem to be spinning correctly (honestly not sure if it should be still or moving quicker). Here is a link to a video of the bearing: https://drive.google.com/drive/folders/1YxEOmiAEyrkVvL-mX-_aw2ktqnXoECoK?usp=sharing

Wondering if I just need a new bearing?


Use a sharpie/marker to make a mark on the lead screw and pulley, make sure the pulley isn’t slipping on the screw. If it is slipping, you probably just need to tighten up the set screw in the pulley.

If that seems fine, it might be due to the assembly binding a little when the delrin nut and router housing are near the top of the lead screw. If you grease up the washer that fits between the bearing and lead screw, and don’t crank down on the lock nut on top of the pulley, it can help prevent binding. You can also try turning up the drive current to the Z-axis motor (I wouldn’t recommend pushing it too high, though).

Thanks, will check this week.