1680 stem length?

[BradBMW]

Hello all,

Can anyone tell me the correct length of a 702 winding stem for a gen 1575 movement? Mine doesn't allow winding in the first position.

Thanks,

Brad

[alligoat]

So then it's too short, or not short enough? Sounds like a simple fix for a good watchmaker, might require a new stem.

[BradBMW]

I think it' may be too short, but I'm not sure to be honest. I can pull it all the way out to hack and set it. But it doesn't allow me to find the first position. It's almost like it's too far into the movement. Perhaps I pushed it too far in before I tightened the screw?

[automatico]

1...The stem should not bottom out inside the movement when the crown is screwed all the way down.

2...Make sure the watch stops winding before the crown starts screwing down on the threads.

3...There should be enough room between the crown threads and case tube threads in winding position to allow the crown to wind the watch without catching on the threads.

4...The crown threads need to be far enough from the case tube threads in setting position to allow the crown to move far enough to go from setting position to winding position.

 

Sometimes crown clutch problems can mimic stem length trouble.

1...Not hand winding at all.

2...Not enough spring tension in the telescoping crown clutch to allow it to overcome set bridge tension when going from set position to winding position. This could be a movement problem...dry, rusty etc.

3...The clutch assembly coming loose inside the crown.

4...Crown clutch slipping now and then etc.

 

Make sure the stem is cemented securely in the crown.