When the power reserve begins to die

[Phil8352]

I guess my question is, when the power reserve is up does the watch go from keeping perfect time to completely stopped, or does it gradually start losing time by a meaningful amount?

Just looked at my Sub that I haven’t worn in a few days at 6:30 pm and the watch was still ticking but read 4:20 pm

[Easy E]

It will gradually degrade. My experience with a 12 series sub, or comparable 32, is after 48 hrs it becomes quite slow and by 60hrs it’s nothing more than animation. That said, 2 hrs off seems a touch excessive to me. Need to more precisely define “a few days.”


Edit: quite slow = double digit seconds off. Not minutes or hours.

[inadeje]

There are several reasons why the power reserve on automatic watches can develop issues. In my experience the most common is the spinning pendulum bearings deteriorate to the point they’re unserviceable creating enough friction to impede the correct movement of the pendulum or a complete failure of the bearings causing the pendulum to make contact with the case back, also impeding its proper rotation and subsequently not winding the watch. This phenomenon is usually audible to a keen ear if the case back is brought close to the ear and the watch rotated slowly. A scraping noise will be heard or in the case of shot bearings a grinding noise. The other alternative is a mainspring at the end of its serviceable life, but much less so.

[Phil8352]

Originally Posted by Easy E

It will gradually degrade. My experience with a 12 series sub, or comparable 32, is after 48 hrs it becomes quite slow and by 60hrs it’s nothing more than animation. That said, 2 hrs off seems a touch excessive to me. Need to more precisely define “a few days.”


Edit: quite slow = double digit seconds off. Not minutes or hours.

Worn it maybe a few hours here and there since Friday. Watch was purchased brand new from an AD last December. Had exact same issue with an LB purchased grey (Takuya) two weeks ago that was originally purchased in October 2020.

[Mystro]

Here is a typical Submariner 12 series Power Reserve test.

Rolex Submariner 41 Power Reserve Test:

07/31/21. wound/set +0.0 @ 7:15am. 3UP. +1.0 @ 9:30pm
08/01/21 +0.75 @ 6am +0.0 @ 7:45pm
08/02/21 -2.0@8am -4.0@1:30pm -5.0@5pm - 6@6:30 -8@9pm …………….…-9@11pm.
08/03/21 6:01am Stopped. Results 70 hours and 46 minutes

[Phil8352]

So it sounds like I have something wrong with both of my Subs? Sweet

[subtona]

Metaphor for life.

[Easy E]

Originally Posted by Phil8352

So it sounds like I have something wrong with both of my Subs? Sweet

Are you winding them at least 40 full turns after they sit for a few days?

[padi56]

Originally Posted by Phil8352

I guess my question is, when the power reserve is up does the watch go from keeping perfect time to completely stopped, or does it gradually start losing time by a meaningful amount?

Just looked at my Sub that I haven’t worn in a few days at 6:30 pm and the watch was still ticking but read 4:20 pm

Expect your watch was fully stopped and when you picked it up it started ticking.

[brandrea]

Originally Posted by subtona

Metaphor for life.

[Phil8352]

Originally Posted by padi56

Expect your watch was fully stopped and when you picked it up it started ticking.

This must be what’s going on…I hope

[alphadweller]

Timekeeping degrades as power reserve goes down. With the 32xx movement specifically, I've observed the accuracy deteriorate after 48h of not wearing the watch, so you trade off accuracy for that 3rd day of power reserve, in my experience.

[ArtieFufkinPolymer]

Just like an izhone, when the power reserve starts to deteriorate past 80%, that’s when you go to your local RSC and ask for a battery replacement

[ArtieFufkinPolymer]

Time to visit the RSC and ask for a battery replacement

[Tools]

Originally Posted by Phil8352

Worn it maybe a few hours here and there since Friday. Watch was purchased brand new from an AD last December. Had exact same issue with an LB purchased grey (Takuya) two weeks ago that was originally purchased in October 2020.

This is going to lead to erratic time keeping.

A watch likes to run in a very narrow bandwidth near the top-mis of it's power reserve. It does not keep the same accuracy throughout it's power reserve, it changes. When it gets down to very low power, it may actually speed up because the escapement only moves through part of its range - ticking faster.

Keep your watch wound for its overall health.

[Phil8352]

So is it best practice to wind it every day, even if it’s still running?

[rolph]

It can lose time as the power reserve depletes, which is why it read 4:20 pm instead of the actual time.

[cascadez71]

As some posters have noted, 32series likes to lose time as power reserve depletes. When 32series loses excessive time even when wound fully, it is time for service or repair. Personal experience.

I think the 31series tends to speed up when its due for service, but I may be mistaken.

[Onequik135i]

I have both 31 & 32 series, my BLRO readings on my timegraph fully wound D/U position has a dead on trace (does not loos or gain) along w a 275 amplitude. But after wearing it in rotation l do notice it running a few second behind after 5 days or so if I recall of periodic observation. And I like to wind my watches every other day to prevent them from stopping. Now the two 31xx subs they always run +2 or so w a 300 ampltidue & never run - at any given time.