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Omega Bumper 351 Advise - Seconds Hand jitter

Dmitry
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Dmitry Watch Enthusiast

Dmitry

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Hello team, 

undoubtedly there are a few afficionados of the 351 Omega bumber here. I really like this movement and have recently picked up and restored a non-runner. Common ailments - snapped driving wheel on the third wheel, snapped bumper spring, broken mainspring.

It runs well now, but the seconds hand gives me attitude. I have lost the original seconds hand and replaced it with some gp .17 matching one, however the replacement has a tube, while the original does not. 

Please have a look at the video of how jittery the movement of the seconds hand is. I am interested in learning about the potential causes of this jitter. 

Thank you.

ezgif-5-a53893179c.gif

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Kalanag Super WRT Addict

Kalanag

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This typically occurs when the dampening spring for the seconds pinion is not placed correctly (on the wrong side of the pinion) and has no tension. The red arrow in this pic points to the spring:

8602F453-EC38-45F2-B6C0-1B4EF0C61862.jpeg.eb85d87770c1d881c1dc49dfc2dc7991.jpeg

Edited by Kalanag
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Dmitry Watch Enthusiast

Dmitry

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2 hours ago, Kalanag said:

This typically occurs when the dampening spring for the seconds wheel/pinion is not placed correctly. The red arrow in this pic points to the spring:

8602F453-EC38-45F2-B6C0-1B4EF0C61862.jpeg.eb85d87770c1d881c1dc49dfc2dc7991.jpeg

I am familiar with this spring and had to adjust it a bit as it was placed too tight and was stopping the watch. Any suggestions on how it shall be placed?

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Dmitry Watch Enthusiast

Dmitry

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47 minutes ago, Kalanag said:

The red line shows how I think the final position of the spring should be when the seconds pinion is in.

BC0D262F-ACE2-48F6-8DB2-D138F409C3F3.jpeg.ac15d654e896727f50a661db6c330c5c.jpeg

so it should push the pinion against the top plate and towards the driving wheel, ubt not too hard, as if it is pushing too hard, it stops the watch?

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