How can a mechanical pocket watch wind itself from movement, and does it really get damaged if wound "too much"?

Question

Today I received the mechanical pocket watch that I had recently ordered. It was this one: https://www.trendhim.se/guldfargat-mekaniskt-retro-fickur-p.html#full-gallery

I find it extremely fascinating to just stare at the mechanism. It's hypnotizing. But the instructions (consisting of one small square-sized little piece of paper) worry me a lot. They mention two things in particular:

1. The watch can be wound either by movement or by using the "knob" or "crown". But why do the manual winding if it winds itself from simply you walking around with it? Can that really wind it up to any significant degree? And how does that work mechanically? I don't understand that.

2. They make a bold point of claiming that you must never turn the crown/knob more than five rotations or until you "start feeling a resistance", or else you "may damage the watch". This has me extremely worried because it's very unclear to me when it supposedly "gives resistance", and I must have turned it more than five rotations several times already now, in spite of reading that warning. I'm now paranoid that I may have already damaged the fascinating but apparently fragile thing. If I have indeed ruined it, will that show immediately, such as it just stopping suddenly, or will it result in slow and gradual degradation of the time-keeping or something along those lines?

I thought I was very careful, but I just can't tell (so far) when it's supposedly "fully wound up". I don't understand why it would get damaged from getting "too" wound up, nor do I grasp why it's necessary to begin with if it auto-winds itself from movement. (Except after you've slept, perhaps.)

Answer 1

I expect it works the same as a wrist watch type ; There is a weighted wheel , that is one side is substantially heavier than the other side . When the watch is moved , the heavy side of the wheel rotates so it is on the bottom. By using a ratchet , this rotation winds the main spring when rotation is in the correct direction . In the opposite direction the wheel turns freely. The self -wind will not over wind , but ,like any watch, the user can over tighten the spring with the knob. I had an old Omega self wind wrist watch , it never needed wining unless not worn for days. Unfortunately ,the ratchet failed on the rotating weight wheel and repair was not reasonable ( I have forgotten the specific reason).

Answer 2

First of all, this is very much depended upon the implementation.

Having said that, the chances that damage occurs during self winding are minimal. It would take a pretty bad design to do that, and usually the people that still make watches are very experienced and with attention to detail.

So the only case that you might actually "hurt" the mechanism is by over stressing the spring, however you'd need to apply significant force on it, which - judging by the way you describe the mechanism - I doubt very much ever happened.

Regarding the question, of how you might damage the watch by winding. The torsional spring (sometimes called mainspring) usually look like something of the following:

The usual way that you can really damage it is by overstressing it and breaking it (see below example). But as you can understand a) it requires a lot of strength to do that, and b) if it breaks then the watch cannot work anymore.

Bottom line, I think you are ok.