What is acceptable? Mechanical precision of vintage watches

krillan50 · Jan 8, 2021

Hi there, my mechanical omega seamaster, cal. 286, runs for about 40 hours with precision +/-30sek. Is this acceptable or does this mean that it needs service? Are there any rules according precision/need og service😀?

Regards Kristian

janice&fred · Jan 8, 2021

My rule of thumb is if a watch is consistent in it's variation from day to day then it's probably healthy. Erratic variation is what I watch out for. Of course if the variation is wildly out of time that's a different story. Your oldie doesn't seem that far off at 30 sec.

Archer · Jan 8, 2021

What is "acceptable" is highly variable depending on who you are talking to. I recently had someone send me a watch for service, and they said that the timekeeping was good, but since it didn't have a service history he wanted it serviced. I asked him how it was running, and he said it was only a minute out per day...

Some people (myself included) would never live with that sort of timekeeping, but for him it was fine. It will go back meeting my standards, not his, and I know he'll be happy. It's going back averaging +6 per day, with positional variation of around 11 seconds over 6 positions.

Now to your question of the watch needing service...

Timekeeping is a very poor indicator of the need for servicing. Here's an example illustrating just that - running far better than your watch, yet the movement was completely dry inside:

If my watch keeps time well, does that mean it doesn't need service? | Omega Forums

The big questions is, how long since the watch was last serviced? That is your best guide.

wagudc · Jan 8, 2021

Listen to @Archer ^^^^ Nothing more to be said here.

malilis · Jan 10, 2021

Indeed, the consistency is what matters .. whether 15, 30 or 45sec/day shifting is not very important as long as it is the same every day ! Ofcourse it is nicer to have a watch that is within COSC ... but if we are looking at a vintage 75 years old ...

What is acceptable? Mechanical precision of vintage watches

krillan50

janice&fred

Archer

wagudc

malilis

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