Breaking-in and positional regulation

[Annapolis]

Just wanted to share.

Got my SMP300 (blue on blue) a while back---had the clasp-stuck-closed-while-on-my-wrist issue a week in, but got the watch off and the AD took good care of me. (Still makes me a little nervous, but hasn't been an issue since getting the new clasp.)

Anyway, right out of the box, I noticed that watch was gaining---probably more than 6 seconds a day. Borderline out-of-spec, perhaps, but I know that spec is based on an averaging of several positions.

I decided to try some positional self-regulating. Once I began consistently storing the watch at night (and on days when I wear another watch) face-down, I noticed that it began to run more slowly, but was still a bit fast.

Now, after several weeks of doing this, the watch is pretty much +/-0 seconds per day, and is holding steady.

I have to think that's a combination of the self-regulating and the movement having gotten broken-in. Just sharing... I don't know why. Because if OFers don't care, who else will? 😀 But it does impress me, that Omega's qc process seems to be able not only to analyze a watch's performance at the time of inspection, but also to anticipate how that watch will perform once it's out in the world for a while and things have settled in a bit. (I had a similar experience with a Submariner last year---from new-out-of-the-box to daily-wear for a few months, a significant improvement in timekeeping.)

Will add a picture, since that's just good forum etiquette.

 

[DoctorEvil]

I've noticed that with my SMP midsize as well. On the watch winder, it gains just over 6 secs a day but if worn daily on my wrist and resting it dial up overnight, it only gains 4 to 4.5 secs a day.

If you check out the COSC website it says that under test conditions all certified chronometer movements have an average daily rate of -4 to +6 secs per day but under "real world" conditions the rate may vary.

Mine says "Hi"

 

[derv]

I noticed the same with my now sold Seamaster 300 and my current 3861 Speedmaster. If I fully wind it and leave it face-up on my nightstand, it’ll gain 6 seconds or more in 24 hours. Face down it might gain 1 or 2 seconds. If I wear it instead and put in on my nightstand for the night it’ll only gain 2 seconds…more reason to wear your watches and not let the turn into safe queens!

To be fair, I’ve noticed the same behavior with a 126200 DateJust. My 1861 Speedmaster, however, is very consistent on or off the wrist…probably gains 3 or 4 seconds a day.

 

[SkunkPrince]

Watchmakers I have spoken with almost universally claim that tribilogy and micropolishing is nonsense. Of course that's not true, and their assertion you're not paying attention or wearing the watch differently is completely correct, but....

I've never heard of a watchmaker who has marked the location of the wheels in the train and put them back exactly where they were, and actually studied the effect.

Yes, the watchmakers are going to come after me, and fine, you do that. Whatever makes you sleep at night. Quite honestly, the variations in the escapement are probably an order of magnitude more than the variations in the train friction.

I once asked the folks who fixed the timing of my (former) Speedmaster 1861 what they did to make it keep time so well. What was I told?

"We trued the wheels."

Micromechanics is fascinating. You look at these wheels with an electron microscope (yes, not me, sheesh) and they look rough. Run them for a while? They smooth out. "Lubricants!" they say. Oh, now you consider tribology?

Lots of fun stuff going on. 😀

 

[SkunkPrince]

And now that I review... "oh, positional variation is a thing!" well yeah, duh?

 

[Archer]

SkunkPrince

Watchmakers I have spoken with almost universally claim that tribilogy and micropolishing is nonsense.

Some context of these statements would be great, but I can tell you I don't believe that micro-polishing or tribology are nonsense. They are an integral part of making watches function well.

Watch pivot lubrication would be on the left side of the Stribeck curve, so under boundary lubrication. As one poster described it previously, this is sort of like waxing your skis so they glide over the snow, and so the underside of the skis don't really have potential to wear until the wax breaks down.

SkunkPrince

I've never heard of a watchmaker who has marked the location of the wheels in the train and put them back exactly where they were, and actually studied the effect.

What effect do you believe doing so would have on the movement's performance?

SkunkPrince

I once asked the folks who fixed the timing of my (former) Speedmaster 1861 what they did to make it keep time so well. What was I told?

"We trued the wheels."

Do you understand what this even means in the context of watchmaking?

What was the timing issue that needed to be fixed?

SkunkPrince

Micromechanics is fascinating. You look at these wheels with an electron microscope (yes, not me, sheesh) and they look rough. Run them for a while? They smooth out. "Lubricants!" they say. Oh, now you consider tribology?

Brand new pivot under an electron microscope....



Yes, you can see that there are very slight imperfections...



When these "smooth out" what is it exactly that you believe happens to the performance of the watch?

SkunkPrince

Lots of fun stuff going on. 😀

Are drugs involved?

 

[SkunkPrince]

Archer

Some context of these statements would be great, but I can tell you I don't believe that micro-polishing or tribology are nonsense. They are an integral part of making watches function well.

You are one of the few I knew would know about these things.

Archer

What effect do you believe [putting the wheels back in the same orientation] would have on the movement's performance?

I'm thinking a minimal but perhaps measureable decrease in the "running in" effect some people notice.

Archer

Do you understand what [truing the wheels] even means in the context of watchmaking?

I believe so... the wheel is flat and perpendicular to its pinion.

Archer

What was the timing issue that needed to be fixed?

There was schmutz on the dial, and it was running fast about 15 seconds a day. I asked them to regulate that since they were "in there anyways". I certainly didn't ask them to true the wheels or do anything else, but it seemed like they must have done a full service on the movement. After they returned it, it was consistently +2/day and I'm sure by sheer coincidence, was returned to that spec after each subsequent service.

Archer

When these "smooth out" what is it exactly that you believe happens to the performance of the watch?

I wasn't considering the pinions at all, just the interface of the wheels together.

Archer

Are drugs involved?

Nope. 😁

By the way, the "them" in this case are the watchmakers associated with Ashford.com before they sold the company after 2001. Great customer service beforehand, and "go away, you bother me" after.

 

[Archer]

SkunkPrince

I'm thinking a minimal but perhaps measureable decrease in the "running in" effect some people notice.

So the only real effect maintaining the orientation of wheels inside the watch would have would be due to an out of round condition on the wheels that might be present. This can sometimes be observed on a timing machine that has the capability to track the balance amplitude and timekeeping over a longer period of time. My machine can do this, and although I don't have a photo handy what you will see is the amplitude graph in particular form a wave like pattern, and by measuring the peak to peak distance on the wave and calculating the period, you can tell what specific wheel has the OOR condition. But most of the time these have no real effect on average timekeeping - if the watch runs at a constant say +2 seconds in one position, or if it oscillates in a wave that goes from 0 to +4 and back to zero over time, the result is going to be the same on the wrist as it will all just average out.

I don't see any technical reasoning why this should have anything to do with what people on forums characterize as "running in"...

SkunkPrince

I believe so... the wheel is flat and perpendicular to its pinion.

Yes, so if a wheel is not perpendicular to the pinion, it can look like this:

This wouldn't be the kind of issue that I would expect would cause the sort of timekeeping change you had in your watch, so it's a bit odd for them to give you this answer.

SkunkPrince

I wasn't considering the pinions at all, just the interface of the wheels together.

Pivots, pinions, and the wheels are all important in transmitting power. Wear in the wheel and pinions is rare, and if you look at a brand new wheel and one that has been in use for years, the pinion leaves and the teeth in the wheels will look the same. The pivots are the primary wear spots, because they are under the most load and have the most friction.

But even if the pinion leaves and teeth of the wheel somehow "smooth out" what exactly do you think this causes in the watch to change the timekeeping?

Let's assume it's less friction, so what then? Well less friction would cause greater balance amplitude - that's plausible, but if we take the time to understand the relevance of what that balance amplitude increase is likely to be, this is where this theory starts to fall apart.

Indeed the balance amplitude of a watch will increase slightly over time once it's first assembled new or after a service - we are taught this in school, which is why I let the watches I service run overnight typically before I perform any timing checks and adjustments on them. And overnight is usually all that's needed for a movement to reach the amplitude it's going to reach, so I can run it day after day and it's not going any higher. But lets for a minute believe the theory that the balance amplitude will increase by some amount. Whatever that amount is, it will be small - single digit amplitude increase for sure, otherwise we would have potential rebanking issues with excessive amplitudes on these modern watches that already have very high amplitudes, like this Speedmaster:



You can't go a whole lot higher here without having rebanking.

A good way of understanding this is to look at what the timing specs Omega uses for watches, and what changes Omega expects to happen when the balance amplitude drops over a 24 hour period. For Omega's COSC watches, they have an allowed Delta of 12 seconds over the 5 positions at full wind, and after 24 hours hours (when the balance amplitude will have dropped a good amount) the Delta is now allowed to be 15 seconds. This is a 3 second change over a potential 40 degree or more drop in balance amplitude, so the few degrees of theoretical amplitude change after a watch runs in and the wheel and pinions "smooth out" are essentially of no effect on the timekeeping.

Cheers, Al

 

[SkunkPrince]

Maybe you can tell me this, I've always wondered what can happen to a watch in shipping and whether this can be seen on the wrist? Not so much coming back from service but a used watch that you'd buy from someone else on the forum, for example.

And now that I think of it, I was told that in a shock resistant watch that the jewels always return to the exact same position after a shock... but I've seen a change in rate in a dropped watch (on the carpet) take a day or two to return to its previous value. So what is the tolerance (so to speak) on "exact"?