[Movement Question] - Why do we need to apply a gentle shake on the watches with manual-wind movement to start ticking?
Hey everyone,
I have a question for the movement enthusiastic guys here!
I own a watch that uses a Sellita SW210-1 (CW C65 no date) and I have 2 options to wind the watch:
- Wind the watch just a few times and then apply a gentle shake on it so the hands will start to move or;
- Wind the watch a few more times and the hands will start to move automatically.
Does anyone know why?
Thanks!
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The reason is that you need to wind the main spring up enough so it has enough power to start kicking the balance wheel back & forth. It will do it with less power if you shake it but really I would just fully wind the watch, that's what I do with mine
Not an expert, but 2 scenarios occur to me.
Least likely, debris jamming that gets shook loose.
More likely, if being wound from zero, I'd guess that there's not quite enough power to start from a stop and the shake just gets it moving enough for the light wind to take over.
Either scenario is a bit concerning as debris is obviously a problem, but in #2 it might be a lubrication issue.
Again, not an expert & I may be WAY off base
Mechanical watches should be fully wound. Are you saying that after fully winding it needs a shake? Or it sometimes requires a few winds to start up. I have some that start right up and others that migh take from 5-10 winds before ticking.
Inertia - The physical force that keeps something in the same position or moving in the same direction unless acted on by another force.
If you wind the mainspring only a little, it doesn't have enough energy to break the inertia; however a little shake will break the inertia and then the mainspring will keep it ticking. If you keep winding the mainspring it will eventually build enough potential energy to break the state of inertia on its own without the little shake.
Inertia - The physical force that keeps something in the same position or moving in the same direction unless acted on by another force.
If you wind the mainspring only a little, it doesn't have enough energy to break the inertia; however a little shake will break the inertia and then the mainspring will keep it ticking. If you keep winding the mainspring it will eventually build enough potential energy to break the state of inertia on its own without the little shake.
Yeap, that sounds reasonable. It is always nice to go to bed a little less ignorant. Thanks!
Nobody has a better memory of physics class than I do?
IIRC, the coefficient of static (non-moving) friction is a bit higher than the coefficient of dynamic (moving) friction. So it takes a bit more force to get something moving.
Nobody has a better memory of physics class than I do?
IIRC, the coefficient of static (non-moving) friction is a bit higher than the coefficient of dynamic (moving) friction. So it takes a bit more force to get something moving.
And the wasps? Where do the wasps come in?
I wonder if, theoretically, a watch carefully wound from unwound to fully wound would not self-start since no power is released by the escapement until the mainspring starts oscillating.
*hairspring, not mainspring
I just fully wind my mechanical.
PS nice watch