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  1. moscow Dec 3, 2015

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    Hi everybody I've got a vintage SM 300 I have I've had for a good while now it is keeping superb time but I've noticed the second hand is a bit Irregular And jumpy it runs smooth then it will slight pause and then jump hardly noticeable unless you sit there staring at it it hasn't been serviced for a long time is this why Or has anyone experienced this before wait for your feedback thanks
     
  2. VetPsychWars Wants to be in the club! Dec 3, 2015

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    Omega watches have "indirect seconds", which means that the second hand is driven by a separate wheel not part of the train. There is a tension spring on the second hands because there's some slack in the system, and if that spring isn't set just right, the second hand will jump.

    Note also that this could just be an artifact of you staring at it, too.

    Tom
     
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  3. Canuck Dec 3, 2015

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    image.jpeg

    Older Omega automatics with centre sweep seconds hands use a sweep pinion drive wheel and centre sweep pinion arrangement as shown on a manual wind vintage Omega, in the attachment. The pinion that carries the sweep seconds hand is a "idler", and these are prone to cause a jumping seconds hand. The tension spring on the pinion is there to minimize the jumping, but the tension must be right. Later Omegas (calibre 550 for example) are quite a different design, but the pinion for the seconds hand is still an idler with tension spring. No harm will come from the jumping seconds hand, and it is hardly worthwhile falling over backwards to solve it. It might well be left to attend to at the next service.
     
  4. flyingout Dec 3, 2015

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    A cal 600 that came back from service earlier this year. I used a local watchmaker so I drove it back the same day to have it straightened out.