The CNC system's Y-axis arms each have two bearings. Over time, these bearings can wear out and will eventually need to be replaced. If you notice a loose bearing ball, it's a clear indication that the bearing needs replacement. Since each side has two bearings, we recommend replacing the bearings on both sides when one side is due for a replacement.
While it’s possible to lubricate the bearings using the lubrication nib on the inside, this process can be quite time-consuming.
This video demonstrates the procedure for replacing the bearings on the CNC AutoBlaster.