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Balance staff - roller and hairspring

p2n

By p2n
in Watch Repairs Help & Advice

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p2n WRT Addict

p2n

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I need to replace a balance staff on a pocket watch. I've never done this before and this one looks a little unusual compared to what I see in the various videos I've seen.

It's from an old (almost) fusee watch. The hairspring and roller are on the same side. How do I remove them without causing damage to any of them?

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The almost fusee - the fusee cone and spring are gone and there is just a solid wheel in place.

P3270031.thumb.JPG.3e94403053fe07d5902673881633eae6.JPG

 

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p2n WRT Addict

p2n

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I've got a roller remover - I was just worried it would damage the hairspring as it's right below.

It doesn't show in those images but the pivots are bent. It runs with low amplitude DD and stops DU

P4150002.thumb.JPG.03ee3679ae314e8003ab1ec1fa0aeeb6.JPG

 

 

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khunter WRT Addict

khunter

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Do you have a replacement staff? I'm thinking that getting one may not be as easy as you might think, especially with this type/age of movement, without a donor movement at least. If great care was taken, and you did some annealing, you could possibly straighten the pivots, as the older watches were more forgiving in the procedure, the steel wasn't quite as tempered/brittle.

Another option would be a remover like this, and there are "screw down" types as well that would further protect the hairspring.

30070.jpg

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p2n WRT Addict

p2n

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I have a bag of assorted balance staffs. Was hoping to find a match - but I can't even start until I can measure it.

I wouldn't know where to start with annealing unfortunately.

Maybe I'd better park this one as well until I've a little (lot) more skill.

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