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Would you consider this acceptable performance for a 1940s Bulova?

patchwerk

By patchwerk
in Watch Repairs Help & Advice

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patchwerk Member

patchwerk

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I recently serviced a Bulova 10BM from a 1917-H US Military Watch and cant decide if I need to redo it. The amplitude is solid but the rate is rather eratic over long periods like 14 hours. The watch has ran for several days now after servicing

 

This first reading starts a little bit after a full wind (so maybe it is caused by the mainspring weirdness that happens at full wind) and goes for 13 hours

This second one is somewhat later and covers 6.5 hours of run time. The rate is steadier but still has the 10 second deviations jumps.

Would you be satisfied with this for a watch from the late 40s/early 50s? I know a lot of people dont do long term measurements like this so am I just over analyzing it?

 

image.thumb.png.73896f708defa3044c51b81ece02a8ba.png

 

image.thumb.png.d40dc89d881b452917f4c2366c631ebb.png

 

 

 

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AndyHull Distinguished Member

AndyHull

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I would suspect there is still some slight wear or perhaps dirt causing issues, but given the age of the watch, I personally would be reluctant to do much more to it.
image.png.f003c431d58f56f062d66a9e81d617f2.png

Any idea what caused this little glitch?

Also if you look at the variation in the amplitude, it appears to have a very specific period to it. This suggests perhaps slight eccentricity, localized wear, or dirt on one of the wheels or perhaps the second or tube hand rubbing.

Depending on the regularity of this error, you may be able to figure its source out.
 

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yankeedog Distinguished Member

yankeedog

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Military watch ? War time vintage?God only knows what stories it could tell. What it is telling me now, is that it is a well serviced , well worn watch.Speaking as an old Grunt, I would tell you that we don't like to be poked any more than is necessary.

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