how often should i (can i ) wind the moon pro?

rudagger

Ok, I'll wade in again and let people mock me

robinhook

Well... This is not what basic physics says. In a basic pendulum system, the period of oscillation is determined by G and the length of the pendulum, not by the amplitude. Similarly, in a balance wheel system timing is determined by the Elastic modulus (equivalent of G) and the length of the hairspring (equivalent of length of the pendulum). Again, amplitude is irrelevant to the period of oscillation.
https://en.wikipedia.org/wiki/Pendulum#Period_of_oscillation

Amplitude does affect how the system react to interruptions or other inputs from the outside, such as movements or positional differences, and higher amplitude means the period of oscillation is more stable and less likely to be distorted. However, higher amplitude does not make the watch run faster, and lower not slower.

robinhook

Well... This is not what basic physics says. In a basic pendulum system, the period of oscillation is determined by G and the length of the pendulum, not by the amplitude.

Nobel Prize

Good morning,

This is a friendly reminder to all members to wind your watches.

Best Regards

S

Evitzee

Is it ok to wind it 'back and forth' or do I have to continuously wind it in one direction only?

Archer

Basic physics isn't enough in this case...

The balance in a watch is a much more complex system from a physics point of view than a simple pendulum. People often say that a pendulum is analogous to a balance, and I've even used this analogy myself as it helps people visualize the basic back and forth motion of the balance, but the balance is a very different system when it comes to sensitivity to amplitude.

The balance amplitude absolutely affects timing, and this is despite watch designers taking great pains to make the system isochronous. To illustrate here is my own Speedmaster with a Cal 861, and I've let it run down for 2 days and placed it on the timing machine:



As you can see the balance amplitude is around 120 degrees, and the rate is around -23. Now when I fully wind the watch and do the same check:



Amplitude just under 300 degrees, and the rate is slightly positive at just under 3 seconds per day.

Now what direction the timing moves when the amplitude drops depends a great deal on the design of the movement and how it's adjusted, so not every watch is going to slow down or speed up when the torque from mainsprings drops, and the amplitude lowers. But it is a fact that it does change.

Cheers, Al

Omegafanman

Many thanks for this detailed info - very interesting so see it tested. If you have time to reply how does that compare on a modern Omega Co-axial with double main-spring barrels (assuming it is not being worn or moved). Also how does running the chronograph (or not) impact the power reserve? On a DSOTM (off wrist) using the stop watch did not seem to make a big difference in power reserve time or accuracy but it was a very very rough test. Picking up on your note that not every watch will slow down I did read a quote from George Daniels that ''the modern methods of springing and adjusting watches have eliminated the necessity for constant power''

Archer

There's a lot to unpack here...

I don't have a co-axial with a double barrel in the shop, so I haven't done this test with that sort of watch, but let's just say that Omega specs account for (expect) the drift in timekeeping as the mainspring winds down.

Now me being pedantic...running the chronograph will not affect the power reserve, because the power reserve is a fixed value based on the length of the mainspring and gear ratio (number of barrel turns and number of center wheel turns). It's designed into the watch, so it doesn't change unless one of those things changes. What does change is how long the watch will run before the load exceeds the torque delivered from the mainspring.

Second thing is it depends entirely on the type of chronograph it is. A horizontally coupled chronograph will typically experience an amplitude drop that is significant with the chronograph running - for example Omega allows this to be as much as 40 degrees. For a vertically coupled chronograph, I would not expect the amplitude drop to be significant at all - few degrees at most on a constant basis.

As for modern the Daniel's quote, well I'm not sure I would go that far. I suspect that was in context of promoting his escapement, so something I would take with a grain of salt to say the least.

Cheers, Al

rudagger

OK, I'll wade in again and let people mock me.

rudagger

I really don't think it's a stupid question to ask how often a person should / should not wind a watch.

rudagger

- Does the graph show much of a difference at 12 hours vs full wind?

rudagger

- If there is a difference in accuracy, how much more accurate would the watch be with winding twice per day?

rudagger

- What exactly is the downside implied in the manual by winding it more often?

rudagger

If someone gave a hypothetical answer to the OP (without my post here), "on my watch, winding twice per day would move the accuracy from gaining 8 seconds per day to 4 seconds per day. However, the lifespan of the spring is greater with less frequent windings, and with more frequent windings, the power reserve will start to decrease. So all in all, for me it's not worth winding twice a day".

rudagger

I think the above questions are quite logical, and to me, are the type of information that someone would post if they wanted to help rather than mock. And yes I realize that quartz would be more accurate. But if a guy asks the question like the self-proclaimed NOOB OP, why not save the derision and have an intelligent answer?

Swissmister

A simple question requiring a simple answer, sans derision. Wind it once a day.