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Tool/how to remove stem from Girard Perregaux 21 movement

macster5
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macster5 New Member

macster5

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Hi, I bought a Girard-Perregaux Calibre 21 movement from EBay. It wasn’t running more than a few seconds at a time when it arrived, but I saw that the second hand was bent so I straightened it and now it’s running swimmingly. I’m in the process of finding an appropriate watch case (any advice on how to do that would be greatly appreciated as well), but first I was wondering how do I take out the stem? My guess is that I need to loosen the tiny screw nearest to the stem? What size screw is this and what size screwdriver would I need? This screw is considerably smaller than all the the others on the movement and also looks damaged. image.thumb.jpg.d4793f722ef8a13053ac4f5a5eaef5cd.jpg

oldhippy Distinguished Member

oldhippy

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The screwdriver blade should be a little bigger then the slot of the screw  that is damaged, you don't want it to slip, but not to wide as you do not want to mark the the cut out sides of the plate. 

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PaulnKC WRT Addict

PaulnKC

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11 hours ago, macster5 said:

Hi, I bought a Girard-Perregaux Calibre 21 movement from EBay. It wasn’t running more than a few seconds at a time when it arrived, but I saw that the second hand was bent so I straightened it and now it’s running swimmingly. I’m in the process of finding an appropriate watch case (any advice on how to do that would be greatly appreciated as well), but first I was wondering how do I take out the stem? My guess is that I need to loosen the tiny screw nearest to the stem? What size screw is this and what size screwdriver would I need? This screw is considerably smaller than all the the others on the movement and also looks damaged. 

You are correct - that small screw closest to the stem is what you need to loosen in order to withdraw the stem.

NOTE: you only want to loosen that screw about 1.5 turns. So, make sure it's not loose when you start, then unscrew 1.5 turns. You made need to push down on the screw just a little when pulling it out.

oldhippy's advice on size is good. My guess is that should probably be a 0.8 mm (yellow - if you are using Bergeon screwdrivers).

The base movement for that is a Peseux 335. So, you are looking for a case to fit that. But it's not an easy task to find a case for an old movement like that (at least it wouldn't be easy for me). I'd suggest eBay. Find a complete watch with that movement. Even if the movement isn't running - it's likely to have a number of usable spare parts for your project.

-Paul

Edited by PaulnKC
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PaulnKC WRT Addict

PaulnKC

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On 5/7/2020 at 6:14 AM, PaulnKC said:

You are correct - that small screw closest to the stem is what you need to loosen in order to withdraw the stem.

NOTE: you only want to loosen that screw about 1.5 turns. So, make sure it's not loose when you start, then unscrew 1.5 turns. You made need to push down on the screw just a little when pulling it out.

oldhippy's advice on size is good. My guess is that should probably be a 0.8 mm (yellow - if you are using Bergeon screwdrivers).

The base movement for that is a Peseux 335. So, you are looking for a case to fit that. But it's not an easy task to find a case for an old movement like that (at least it wouldn't be easy for me). I'd suggest eBay. Find a complete watch with that movement. Even if the movement isn't running - it's likely to have a number of usable spare parts for your project.

-Paul

BTW - macster5,

I recently acquired a couple of Gyromatics. One is based on the Peseux 336 and the other based on an AS 1361. So, I may be posting some pics and questions on those here.

-Paul

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