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Pocket Watch Running Fast

HorologicalHobby
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HorologicalHobby Watch Enthusiast

HorologicalHobby

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General question. I cleaned, and oiled a pocket watch, and now its running at 700 seconds fast a day, what would you expect the problem to be. Is this a magnetizing issue, I assumed it wasn't because they are normally like an hour fast a day. Or is there something else it could be?

 

I understand that diagnosing something like this isn't very easy, but I figured it was worth a shot.

 

Also, the hairspring is clean, no debris are causing it to be shortened.

 

 

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WillFly Distinguished Member

WillFly

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It may well be magnetised, given that amount of error, so you could try demagnetising at as a starter. If that doesn't work, then it needs regulating, and Mark has recently done 3 videos on the timing and regulation - well worth a look.

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clockboy Distinguished Member

clockboy

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It could be magnetised or it could be oil on the hairspring. Check the hairspring as it oscillates with a loupe to see if all of the coils are free running. To check if it is magnetised put a compass next to it if the dial moves it's magnetised.

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HorologicalHobby Watch Enthusiast

HorologicalHobby

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Just cleaned off the hairspring with one dip, same rate, so its not that.

 

I will try demagnetizing soon, I don't have a demagnetizer on me, nor a compass.

 

Would the fact that I have not put the hour canon pinion on, nor the hour setting wheel, influence the timing?

 

Also, it has little positional variance, so its shouldn't be a balance wheel poising issue, though it may need washers under the timing screws on the balance wheel.

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Mark Distinguished Member

Mark

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If you are certain it is nothing to do with magnetism, the balance srping is in perfect position, the amplitude is normal etc etc...

 

Then you need to look at the hairspring as it is pinned to the stud, is there evidence it has been re-pinned and/or is there a tail. 

Does it look like any of the timing screws have been tampered with?

Is it a compensating balance? If so then are the gaps equal? Has it been tampered with?

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