Strange synchronous clock behavior.

ifixit

Joined Nov 20, 2008
652
I like post #14 as well. Over time the rotor shaft end play may have increased due to wear. This causes it to occasionally drift away from the stator poles and skip over some from time to time. Try laying the clock face down so that gravity tends to pull the rotor in toward the poles. This may fix or improve the time gain. Laying the clock face up should have the opposite effect.

Rotor shaft bearing wear can cause the same effect by allowing more lateral movement away from a pole at just the right time to allow it to be skipped. You should be able to physically move the shaft to see end play and bearing play. Compare with a clock that still works.

Fixit
 

ian field

Joined Oct 27, 2012
6,536
I had started to think along those lines, it's about the only possible explanation for it running fast. I just had a thought ! (dangerous at my age)
I can hear that the motor is not rotating at an even rate, this may sound odd, but the rotor is making a whirr - click sound, but another similar motor has a continuous whirr sound, maybe the click is it missing a pole and jumping faster in the gap. Just as tcmtech suggested. Anything at this point is possible I guess
A few mashed teeth could let inertia/backlash jump it forward just as easily as let it slip back.

A long shot - but you never know.
 

Thread Starter

recklessrog

Joined May 23, 2013
985
Well a second look proves it is not faulty gears, but the rotor. The magnet is not as powerful as the one in another timer so I'm concluding
that in effect some of the poles are being missed.
Definitely an odd one and no wonder my electrician friend could not work it out.
Many thanks everyone for the input. Time to chuck the thing in the bin :)
 

ronv

Joined Nov 12, 2008
3,770
Well a second look proves it is not faulty gears, but the rotor. The magnet is not as powerful as the one in another timer so I'm concluding
that in effect some of the poles are being missed.
Definitely an odd one and no wonder my electrician friend could not work it out.
Many thanks everyone for the input. Time to chuck the thing in the bin :)
It's a shame your not closer. I could dig it out of the bin and give it to my wife. :rolleyes:
 
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