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Bent Banking Pin


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Currently working on a Gruen Guild, Semithin, 16 jewel, 12s that is in nice shape for it's age. Seemed like it was just dirty and dry but I've found what might be a problem with the banking pins. One of the pins is bent over quite a bit and has a gouge on the pallet fork side of the pin that pretty clearly shows it was bent over on purpose. The other pin looks a little bent too but not as much.  I don't know if I should clean and lubricate the movement and see how (or if) it runs or try to straighten the bent pin while reassembling. The roller jewel seems to line up between the pins but the fork swings much further on the side with the bent pin. 

One thing I've never done, as I've pursued learning watch repair at my hobby level, is try to adjust banking pins on any other work I've done, and I have very little knowledge of checking the run to banking. The pins appear to be pressed in to the plate and not adjustable. Any help is greatly appreciated.

Gruen 6.jpg

Gruen 2.jpg

Gruen 1.jpg

Gruen 13.jpg

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I would see how it goes first. From the look of the pallet bridge and the screw it has had some very bad treatment. Banking pins are not the sort of thing to play around with, all sorts of problems can happen in and around the escapement. 

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flow-chart-did-you-mess-it-problem-solvi

That has the look of "apprentice marks".

I wonder if the palette bridge gouges and the bent pins are part of a nasty apprentice + screwdriver related incident.

Maybe the screwdriver was applied with a little too much youthful exuberance to the screw and afterwards said apprentice checked it still ticked, hastily buttoned it back up and gave it back to the customer. "Nothing to see here sir. Working fine now.  That will be fifty bucks. Thank you sir and have a nice day."  per the instructions above.

Edited by AndyHull
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