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Help! Broken stem on Patek 5980 with A7750 movement.


mule play

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Hello, friends.

The watch, with the crown open, was bumped off a table onto a hard floor.  POW!

The stem near the crown snapped off.

A bit of research here told me this may be a repairable fix.

I uncased the movement and popped the release clutch to get the remaining stem out of the movement. This is shown in the pictures.

Big questions:

1. where do I source a new working stem?

2. How do I get the Patek crown off the existing broken stem?

3. Anything else to know?

Any help here would be appreciated.

Thank you!

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The stem shouldn't be a problem to source. If you've never done one before the real fun will come when you  try to  cut it to length to fit your movement and case. I'd buy a couple if I were you. I messed up a bunch of them way back when I started watch repair and learned the old watchmaker's rule of "buy  3". One to break, one to lose, and one for the watch! ;) 

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The replacement is a 7750 stem.  The way to have gotten out the stem is soaking it ammonia for weeks.  The chemical reaction would have eaten the material the stem is made of.  There is a watch makers chemical that works faster.  I forgot the name but that is why the stem material is so flimsy.  The crown would have been find and the chemical would have eaten the steam out of there.  It take a long time with ammonia but still works.

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Many thanks, men. Now...about this crown business....

As you can see from the photo, the 'insert' piece that connects the 7750 stem to the crown is damaged. I assume I need a new one of these pieces as well?  What is that inser piece called and where do I get it?

Also, thank you for the note to order 3 stems. I did not know I had to cut them to work in this repair.

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That is a clutch system in the crown.  It is destroyed.  When you push the crown in the clutch releases so you don't put pressure on the stem.  You need a new crown.  Don't risk it.

I have tons of Rolex.  I don't own any AP's sorry.

What I might have is a stem for you though.  Have to look or worst case I can order some for you on Startime.

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Thanks, occb2! I need a Patek crown...which nobody will have. Or can you take a Rolex crown and remove the clutch elements and screw them into the Patek?

Perhaps this is now a salvage A7750 project? Maybe I should sell off the A7750 movement for $100. Then sell the dial and band as parts?

Edited by mule play
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No. Once you compromise the crown off the clutch it will "slip". That is when you turn and feel that clicking.

Sent from my iPhone using Tapatalk

Someone has to have a broken Patek here. The crown is not movement type. It is tube typed though so it would have to be able to be screwed into the proper tube. I would try to contact the authorized seller that you got the watch from. He might be able to sell you just the proper crown.

Sent from my iPhone using Tapatalk

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