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6138B bushing question

Mircea

By Mircea
in Watch Repairs Help & Advice

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Mircea Member

Mircea

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I hope you could help me, as I didn’t find any answer anywhere. I used this forum at large for a million question I had and found a million answers, thank you all for that! And mostly thank you Mark Lovick for the courses and the forum!

I recently finished the revival of a Seiko Jumbo with a 6138B movement. One of the bushing of the chronograph bridge, used for the intermediate minute recording wheel, is in aluminum (or so I think) and seems to be broken, ie the hole is elongated on the wheel side and has a metal protrusion on the other side. There is play of the pivot in the bushing when pushed manually, but during operation all stay in place and operation is normal.

my question is: do I have to change this bushing, and if yes, is it doable just the bushing? The entire plate is around 50$ on the bay. I do not have a lathe, and bushings are not to be found as such…

sorry for the quality of the pictures, is an iPhone through my microscope, I did my best…

Thank you 

 

 

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44B7EAED-F532-4AC8-9315-29411D4062F1.jpeg

BB414C2A-A37E-4B6E-9A83-10C50D67D1A2.jpeg

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nickelsilver Distinguished Member

nickelsilver

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Most likely what happened in the past is the bridge was forced down but the pivot wasn't quite in the hole, and the pivot punched a new one that bled into the old one. From the top it looks like the remaining original hole is holding it ok, does it slop around as far as the slot shows on the bottom? If it's centering in the old hole and is totally free (this will often close the old hole at the top), and the chrono functions ok, I say leave it.

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Mircea Member

Mircea

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1 hour ago, nickelsilver said:

Most likely what happened in the past is the bridge was forced down but the pivot wasn't quite in the hole, and the pivot punched a new one that bled into the old one. From the top it looks like the remaining original hole is holding it ok, does it slop around as far as the slot shows on the bottom? If it's centering in the old hole and is totally free (this will often close the old hole at the top), and the chrono functions ok, I say leave it.

Thank you, nickelsilver, much appreciated!

the original hole is ok, the pivot is free, it is sloping around when pushed with a tweezer, but replaces itself in the original hole. It stays in the hole even when the chronograph is on and minute counting is true and working well. For the last week I wore the watch every day and all keeps the same. I think I will let it be as such for now.

What about changing the bushing, is it doable? Just another thing to learn in the future… and where to find such bushings?

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nickelsilver Distinguished Member

nickelsilver

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You can definitely change it, and it would be the proper solution. But you won't find a commercial one, or a spare part from Seiko. Maybe a jewel would fit but likely too thick. It's an easy and satisfying lathe job, hold off till you get a lathe!

 

There's almost force there, if it's working, and it's yours, enjoy it. When you make a bushing for it you'll like it more!

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Mircea Member

Mircea

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About the force, the history of this watch, at least the one that I know, is something… I posted it in the achievements section, it is really an achievement for me! I learned a lot with this watch or to be able to resuscitate it! And I realized the chance i had with a well preserved watch to be able to have it back to life like I did! All the parts were in good shape, except the crystal, stem and the balance staff (my fault for the latter). So, there should be some Force involved!

Thanks again for your advice!

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