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Waltham A11 mainspring barrel arbor issues.


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I finally stumbled across one of these watches I've been wanting for several years. It ran but poorly so decided to give it a service.  My issue is with the mainspring,  the hook is connected to the barrel lid, and the arbor just slides into the barrel but if you turn it,  only the arbor turns.  Did the hook break off of the arbor because it's stuck to the lid of the barrel? 

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And I discovered the arbor popped out while I was putting the movement back together before.  So I ended up answering my own question.  

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If you look very carefully at the Arbor at one end is a square that goes into the barrel itself. The basically the whole thing has to be together and in the watch to work otherwise it has a habit of falling apart.

Then the mainspring Replacement springs are usually a problem because the end with the hole Isn't the right shape to catch on the hook that's in the barrel wall. It needs to have a little bend and a little bit of taper. This is where sometimes fighting an original new spring is a better way to go.

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