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amplitude question

Rowbear23
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Rowbear23 Member

Rowbear23

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I COA'd a watch (Bulova 7AK) this week but had hairspring problems and wound up needing to replace the entire balance with a donor watch. It's running well right now but I do wonder if you all find this acceptable, dial side down I'm getting an amplitude in the 290s, dial side up i'm getting somewhere between the high 240s to mid 260s. I suspect this might be because the donor balance I am using did not go through the cleaner. It does not have a shock system that makes it easy to clean and oil the balance jewel. To do that I would need to remove the balance and the two screws on the underside of the cock. Should I go through that trouble? I'm a little gun shy since I already ruined one hairspring on this watch and since it is a breuguet overcoil, it is not that easy for me to get the stud back into the regulator arm.

WellAdjusted Member

WellAdjusted

Posted
Posted

This is a pretty common profile. The fixed upper balance jewel is usually crustier than the removable lower one, so you get worse amplitude when the balance staff rests against it.

The watch will spend much more time dial up than dial down, so you may as well have a crack at cleaning it.

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