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7750 Subdial Jewels Pushed Too Far In?


e30m3

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I have a fake IWC 3717 with a serviced A7750 movement - I had the dial off to fix the hour counter and when I put it all back together, I pushed the hands onto the subdial counters WITHOUT a proper 7750 jewel supporting holder. Nothing fell out, but it seems, now, that the hands sit right on top of (touching) the dials. I now have a correct 7750 jewel supporting holder. But if I install the subdial hands with enough pressure that they work (and don't slip when resetting the chrono, etc), they're stick on the dial, stopping the movement. I think one of two things might have happened and am hoping someone has an idea:

 

1. Is it possible that I pushed the jewels PARTIALLY out? that is, they sit further down, now and need to be pushed back up? Is that even a thing? If so, how do I get them pushed back up?

 

2. Maybe the hands need to be re-staked from having been installed too many times?

 

Thanks!

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You cannot support the hour counting wheel jewel when pressing the hand, it is covered from behind.

 

If the hand is too loose, the hand tube requires a gentle 'nip' to close it. This isn't for the feint hearted, it's extremely easy to over do it. 

 

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Actually, that's a great point. I don't know how that didn't occur to me; because both the hour and the minute counter seem sunken. And since the hour can't be sunken, it must be that the hands need a nip, as you suggest. It does sound scary, but I'm out of options. Impossible to buy "IWC" hands separately for the A7750 movement. Tons for Valjoux, etc.

 

I'd take any other ideas, though - what about somehow tightening the clearance of the dial spacer? (The wave washer - compress it a bit; any room to do so?)

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I have tightened the tube on hands before. My method is to find a pinion that is suitable size to mount the hand on. I have a tin full of different size wheels with various size pinions. 

By mounting the hand on a smaller pinion you lessen the chance of crushing the tube too much.

 

If you can't find something suitable, you could try using a very fine needle. Possibly turning it down in a small dremmel chuck using abrasive paper. 

 

It only requires a fraction of a mm.

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