Squeak tweak

What is making this squeaking noise? Is it the eye rubbing on the washer? Is the washer rubbing on the eye tray? Is part of the eyeball rubbing against the eye socket? Is there debris still in the axle hole even after all that cleaning? No. No. No. And no.

I noticed that if I placed my finger gently on top of the left eye's bolt, the squeaking stopped. Hmmmm.

As the eyes move, that bolt is vibrating! Touch the top of the bolt and the vibration stops. Finger up. Squeak. Finger down. No squeak.

So I put a tiny ball of Magic-Sculpt over the top of the bolt just above the nut to absorb the vibration.

No squeak. (Didn't need the WD-40 after all).