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Giuseppe

Should this bridge be replaced? 7750

Question

Hi,

in order to buy appropriate spares in my attempt to service an Omega 175.0083 (7750)  I need some advice:

1.
I've already been suggested to replace MS:
Barrel is Ok and I'm thinking of buying a new MS and moebius 8217 for barrel lubricating as I don't want to spend money on recommended Kluber 125 grease.

Should I consider instead buying a barrel complete (assuming Barrel complete (180.1) comes with MS installed) wich supposedly comes prelubricated ?

2.
Attached image shows automatic device bridge with evident sign of wear from where, to my understanding, the problem orginated: a screw came off
I cant find original part. 
ETA part is different from Omega in that the Omega is larger and partially covers hammer two function and the chronograph cam.

Beside that and since the watch has no crystal back case I think those parts are perfectly interchangeable.

Do I need to replace the bridge or are there alternative aproaches to this problem?

TIA

Giuseppe

IMG_0013.jpg

IMG_0015.jpg

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What makes you suspect the bridge is faulty?  Afraid next screw will have the fate of previous one? What condition is the rest of the watch in. I personally am obssesive and wont let anything but the best get back in the movement, especially the iconic 7750,

Screws are to hold the bridge in place,  accurate positioning is the job for the pins. 

If you will please explain your question in more detail.

Regards joe.

 

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40 minutes ago, Nucejoe said:

What makes you suspect the bridge is faulty?  Afraid next screw will have the fate of previous one?

This is the reason why I'm asking if that sign of wear can compromise how the screw will stay in place.

Despite of those signs I see enough space for the screw to make pressure to the bridge and hold it in place.
And the slot on the lower bridge where the screw fits shows no sign of wear.

I lack in knowledge here and I'm definitely afraid that the screw might fall apart again.

To my eyes the rest of the movement is in perfect condition.

Thanks for answering!


 

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If just concerned about the screw falling off again, you can put a bit of glue on it ,which keeps it in place in slot, do not attempt overtightening the screw?

I see two chisel marks on both sides of the screw slot. You should check the other side of the bridge for effects of chisel impact. The bridge should be perfctly flat and in no way impede free transfer of power to barrel ratchet. 

No soldering,  just glue and watch out for glue seeping furthure to the movement.

So if it winds good it is doing it's job right.

Regards joe

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Loctite has no place in there. Think of the watchmaker who next has to work on this, and bear in mind that may be you.

If the plate is flat and the screw holds it securely in the right place you should be fine.

If you really need to repair this, then the best way in my view would be to drill out the hole oversize and solder a brass bush into it.

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I have seen nail color used as glue fifty years ago, and acetone cleaned it perfect with no sign of chemiacl bonds or discoloration.

Best offcourse is to replace with a new bridge which costs less than any machining.

 

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Fifty year old nail polish or color, when cleaned with acetone? shows no sign of chemical damage to the plate.

Use of heat only as one of last resort. Sorry stuart can,t agree with you, heat can warp the thin bridge plate instantly, The worst nail polish will do is slight surface discolloration.

I have seen nail polish used on hairspring collet and fifty years later no sign of damage is observable.

 

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