Hi all-
I'm trying to fix up a 72B in a 722-946, and it arrived to me with a broken winding stem.  My research/other posts here have shown this is basically unobtainable to replace, but I had a few questions:

1- Can the 70-72 stem be installed in the 72b?  I know the only difference is quick-set-date, but it would presumably be acceptable to be missing that.

2- Barring that, does anyone know the differences/can show a picture of the differences between the two?  I guess I could always pick up a lathe and try to modify it if it isn't horribly different.

Thank you in advance!

All I can offer is that the parts catalog shows the same stem, 401, for all 7x and 8x calbers. Can anyone else offer anything on this?

Not the same stem at all, completely different shape.  Being a different stem shape also means the winding pinion and sliding gear have different hole sizes as well.  Long story short, use only the correct stem.

Thanks UV! I did not think so and was surprised the parts catalog said that.

Quote from: Ultra-Vintage on August 20, 2026, 12:56:15 PMNot the same stem at all, completely different shape.  Being a different stem shape also means the winding pinion and sliding gear have different hole sizes as well.  Long story short, use only the correct stem.

I realized I have a 70-72 as well in my 'TODO' pile (though its missing a bezel, so it might never get to 'do'), and pulled its stem.

They ARE quite similar it appears?  OR is one of these the 'wrong' one?  I was really just hoping I could use the 70-72 and just lose quick-set date or something :D

Oh, top one that isn't broken is the 70-72 out of a 722-916 missing a bezel.  The 72b is out of a 722-946 in need of a service.

Quote from: ErichKeane on August 21, 2026, 09:24:48 AMOh, top one that isn't broken is the 70-72 out of a 722-916 missing a bezel.  The 72b is out of a 722-946 in need of a service.

Probably you misinterpreted these two? What I see is the top stem is 72B and lower one is definitely 70-72.
Show us both movements in question.