The Breitling Watch Source Forums

When i wind my manual Cossie, after each wind the crown recoils a little; that is it rotates a 1/8 turn in the opposite direction. What causes that?

A manual watch has the mainspring attached in two places - the arbor that passes through the mainspring barrel and a hook on the inside of the barrel wall. When you wind a watch via the crown you are rotating the mainspring barrel via the keyless works and tightening the mainspring in the barrel.

When you let go of the crown the mainspring wants to release that tension by unwinding which would turn the mainspring barrel in the opposite direction (as well as causing the hands to spin faster than Driver8's Big Pilot) which in turn would transmit the power back through the keyless works and rotate the crown back in the opposite direction.

The power is prevented from being transmitted through the running train by the escapement that controls the rate, and from being transmitted through the keyless works by a click that is held in place by a click spring and prevents the keyless works from running backwards. The click engages in the winding wheel and only allows it to run in one direction - its the source of the clicking that you hear when winding the watch as it rides over the winding wheel teeth, but then locks the teeth in the other direction (think of a ratchet).

The reason that you get a little bit of counter rotation in the crown is that there is a little bit of play in the winding / keyless works until that click engages.

Gotcha

That's a precise explanation!
Lots of watch info one here. I'm enjoying reading it all. A lot of it seems to be by Roff.
Thanks Roff and to all concerned.

Thanks for the sound-check! (And very true too!)

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Driver8

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