Junghans Strike governor fan

[Paul FM TX]

Hello again. Question related to the fan in a Junghans A21 movement; how critical is the balance of the fan to the strike timing? This fan has a slightly heavy side that it always stops at when I spin it. With all the wheels assembled except the spring barrel, it still stops at the heavy-side-down position. The fan does seem to have acceptable slip on it's arbor though. Just curious on this one.

Thanks:
paul

[Paul FM TX]

Hello again. Question related to the fan in a Junghans A21 movement; how critical is the balance of the fan to the strike timing? This fan has a slightly heavy side that it always stops at when I spin it. With all the wheels assembled except the spring barrel, it still stops at the heavy-side-down position. The fan does seem to have acceptable slip on it's arbor though. Just curious on this one.

Thanks:
paul

[Mike Phelan]

Hi Paul
I would imagine that nearly every fly (fan) ever made is out of balance by some degree. I am not sure precisely what you mean by 'timing', but it should make no difference to anything at all; unless Billy Bodger has been at it, it is as it was made.