Twisted Needle Bearing
Losmandy GM8 with a twisted needle bearing on the DEC axis. This caused binding when rotated. It also caused the DEC axis to "unthread" when the clutch knob was loosened or removed.
Twisted Needle Bearing II
This is another shot of the twisted needle bearing. Note how the needles don't align with the stria in the reflection below.
Bottom Bearing on the GM8
This is the bottom bearing on the GM8 DEC axis. Note how the needles appear to align with the bore stria, indicating that the bearing is not twisted.
DEC Shaft Wear Marks
This is the DEC axis showing the long-term wear caused by the twisted bearing.