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Posted

Hi everyone, my name is Ollie. I’m a motorsport engineering student from northwest England.

I’ve always been interested in the engineering behind mechanical watch movements, so I recently started collecting broken pocket watches with the intention to try to coax them back to life (as yet with surprisingly successful results!).

I have an Illinois pocket watch that came with the winder not attached to the watch. Upon dismantling I found there is a small ‘pushrod’ (please excuse my lack of knowledge), inside a separate winding stem with a square female drive which I assume the winder sits in and allows it to float backwards and forwards, pushing on the ‘pushrod’ so you can change the time. Shown in pictures.

How can the winder stay inside this mechanism, as it just slides straight out (there is no physical way of stopping it)?

I had wandered whether the ‘pushrod’ should be attached through the stem to the winder, which would hold it in place because the end of the ‘pushrod’ is flared preventing it from sliding through the winder.

Thanks, and I look forward to hearing the replies.

 

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Posted (edited)

Does not appear to be broken, looks like a 2 piece stem. I believe it is supposed to be this way. There is supposed to be a collet that screws into the case that keeps the crown from slipping out. 

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Now you're design may be different, but this is the most typical. I have had the segments with the fine slits break off and then the stem won't stay in place anymore.

Edited by FLwatchguy73
Posted

Thanks for your reply!

My crown however doesn’t look as though there is anything physically there to interact with a collet to prevent it from coming out (see picture).

It has to slide up and down inside the outer ‘sleeve’ and push on the ‘pushrod’ to allow you to change the time.

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Posted

Typically on the majority of American pocket watches the movement is set up similar to yours.  This is where the watch itself has no stem as that is in the case. So your movement is fine make sure when you're putting it together to lubricate all of the stuff associated with the setting so it's slide smoothly.

Link down below so you can look at the pictures. It's not really important but you're missing the micro regulator adjustment. You can still regulate the watch fine without it.

Then the crown is most definitely does not look like the right crown for this particular case. It almost looks more like a wristwatch style crown for American watches. I went attached some images you can see what the wristwatch version looks like. Also a picture of the typical pocket watch stem and sleeve arrangement.

https://pocketwatchdatabase.com/search/result/illinois/4927242

wristwatch stem sleeve.JPG

typical pocket watch stem sleeve.JPG

  • Like 3
  • 2 weeks later...
Posted

Thanks for your replies everyone! 

I’m now in the process of finding a stem and collet configuration that works... wish me luck! 

  • Like 1
Posted

This negative-set design was used a lot on early wrist-watches and thin pocket watches, especially those with a low rigid-bow like the one you show. I wish you luck finding something. It's not going to be easy. The good thing is that the sleeve is not threaded into the pendant so the fit has more tolerance. Good luck.

BTW, that image is from the Chicago School of Watchmaking courses. They are very handy for working on old watches, pocket watches in particular. And they are widely available on the internet in digital form for not too much money. I have the hard copy as well as the digital. Today I reference the digital a bit more often. Enjoy.

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