Tightening a pocket watch "split" cannon pinion

[GuyMontag]

I'm finishing up servicing a 1925 Elgin 477 pocket watch and noticed the hour and minute hands are not turning. I figured the cannon pinion needs tightening and confirmed by removing the hour wheel and I could see the cannon pinion and minute wheels turning, but when I put the hour wheel back on only the center wheel arbor turns, not the hour or minute wheels.

I haven't come across this type of split cannon pinion before. Are they tightened in the usual way? If so, I assume I would tighten at the area where the arrow is. Is there anything to watch out for or is it pretty much the same as tightening a "normal" cannon pinion?

 

[nevenbekriev]

!!! This movement is with negative remontoir and stays in setting position when out of the case. This will stop the gears from moving no mater if the cannon pinion is correctly adjusted. You need to switch to winding position to release the geas so they can turn free!!!

I would say that this cannon pinion is more normal than the others, which are considered normal. Yes, You must slightly deform the 'tongue' towards the center to increase the friction. Put something (steel wire, broach... with slightly smaller diameter) in the cannon to prevent too much bending. One must learn to feel if the resistence when setting hands is normal, not enough or too much. Too much will do harm like break the minute wheel teeth or other bad things. Not enough means not reliable hands movement.

 

[GuyMontag]

43 minutes ago, nevenbekriev said:

!!! This movement is with negative remontoir and stays in setting position when out of the case. This will stop the gears from moving no mater if the cannon pinion is correctly adjusted. You need to switch to winding position to release the geas so they can turn free!!!

I would say that this cannon pinion is more normal than the others, which are considered normal. Yes, You must slightly deform the 'tongue' towards the center to increase the friction. Put something (steel wire, broach... with slightly smaller diameter) in the cannon to prevent too much bending. One must learn to feel if the resistence when setting hands is normal, not enough or too much. Too much will do harm like break the minute wheel teeth or other bad things. Not enough means not reliable hands movement.

 

Thatnks @nevenbekriev! I actually figured that out about an hour ago I was a little hesitant to just tighten the cannon pinion as the resistance when setting the time seemed completely normal, and I was perusing an old Chicago School of Watchmaking textbook to see if I could find anything on the split cannon pinion and came across a part where they mentioned the watch going into time setting mode as a reason for the watch to run slow or stop. There is a part of the keyless works that is supposed to be able to take it into and out of time setting mode while out of the case, but I haven't had any luck getting it to work so after replacing the hands I'm just keeping it in the case to check and see if it keeps time.

[JohnR725]

1 hour ago, GuyMontag said:

eyless works that is supposed to be able to take it into and out of time setting mode while out of the case, but I haven't had any luck getting it to work so after replacing the hands I'm just keeping it in the case to check and see if it keeps time.

Yes classic problem of American pocket watches not running out of the case. Then each of the watch companies had of one or more methods of dealing with this which can lead to confusion. Especially for the ones that are not obvious like a screw as to where exactly the screw needs to be to put it into the mode so to run out of the case. At least Hamilton colors their screws are pretty blue color C can recognize what it is but where is supposed to be can be interesting. This is why oftentimes is easier just to run the watch in the case or if you doing timing adjustments just don't Put the dial side components on.