Issue with Hamilton 661 Rotor

Paul Raposo

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Nov 4, 2005
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Cambridge, ON Canada
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Hey all.

I picked up an old Hamilton automatic with the 661 caliber (base Certina 28.45 movement). The watch was winding and the rotor turning freely, but I noticed either lint or hair under the rotor that I couldn't remove.

I moved the rotor lock spring and lifted off the rotor and removed the debris and replaced the rotor. Now the rotor is stiff to turn. It won't swing freely on it's own and when I push it with a toothpick it's pretty stiff to move.

I hand wound the movement so I don't know if the wound mainspring is causing the rotor to be stiff to turn, but I don't think that's the issue.

What did I do wrong?

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Randy Beamer

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Jul 5, 2011
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Hi Paul.
You don't state that you also scrubbed all the "possible" gunk from the gear attached to the center jewel, or that you used new, appropriate lubrication when you reattached the oscillating weight ?
Just the simple things to think about ?

Randy
 
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MrRoundel

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Dec 28, 2010
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Either me or the watch seem to be missing something. I see two, what look like, screw holes on opposite sides of the opening for the rotor's winding gear. What goes into them? It looks like the rotor just tab-locks onto the automatic winding bridge. I just can't figure those holes. Am I daft? (Rhetorical question.) Thanks and good luck.
 
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Paul Raposo

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Nov 4, 2005
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Cambridge, ON Canada
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Well, I figured out what the issue was.

After I removed the rotor I noticed the two automatic cassette screws (near the balance wheel) were a little loose, so I tightened them. They were loose because whoever worked on this watch before I got it didn't get the two gear pivots into their plate holes so they were grinding on the plate when I tightened the screws. Rather than fix their work, they just left the screws loose :rolleyes:

I removed the automatic assembly and spent two hours getting everything lined up.

The rotor now spins correctly, however in the process of trying to get everything back together I lost the bushings on the two pivots, so now they're floating around free.

At least i think there were bushings in the holes, I can't remember and can't tell from my picture.
 
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