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Hairspring balance swap


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Hi everybody ! I have 2 identical pocket watches with the same mechanism. ETA UNITAS 6497/ 6498. I check it and both of them They have exatcly same weight / beating rate and everything. I  demaged the hair spring of the 6498 caliber trying to adjust the time and i want to remove the hairspring of UNITAS 6497 and swap it to UNITAS 6498  . is it possible to work ? Could somebody help me please ? Any idea ? Sorry for my English but all i can do.

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Hair springs are matched to balance wheels so swapping just the h/s could leave you with some interesting timing issues.

However, the balance wheel complete (balance wheel, hair spring, and roller) are the same for both the 6497 and 6498, so just swap the whole balance wheel complete assembly and you should be fine.

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