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Synchronome The Synchronous Sessions is Slow


Registered User
Aug 17, 2014
Lancaster, Ohio, USA
It's an old Sessions electric banjo wall clock, 120V, 60Hz, with the motor that has the outside thin sheet aluminum rotor with holes punched in it. Worm gear drive and all that, and I lubricated it and rebuilt the power terminal block (it had disintegrated to powder) and to show its gratitude the thing runs about five minutes slow in 24 hours. The motor does make a steady bumping noise, but normally that doesn't affect timekeeping.

I didn't think clocks run with a synchronous motor ever did this, or could. The hands aren't dragging on the glass, and I'm pretty sure they're not slipping (but I'll disassemble it again to make sure.) Any other suggestions?

I'm prepared to put in a quartz movement, which I don't think the customer would mind all that much, but still.

Mark Kinsler