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Discussion Starter · #1 ·
Hello,
Newbie here. I'm pretty new to watchmaking and just starting out as a hobby.
So far, i've successfully serviced/rebuilt a felsa 1560 and working on couple of others.
I just got done rebuilding a felsa 690 bidynator. I immediaty tried the winder which worked great and even timed to within couple sec/day. But then I found that when i tried to adjust the minute hand it was stuck. Further investigation shows that the cannon pinion is to tight on the center wheel. I have a few of these movements now, both the 1560 and 690's some just for parts and learning but all of the 3 cannon pinions i have seem to tight some where i can barely move them with the adjuster.
I guess there is supposed to be a little bit of friction between cannon pinion and center wheel but how much and how could i loosen then up a bit?
Thanks for any info.
 

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Craftsman
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1,993 Posts
If you could show us a picture that would help. Did you apply appropriate lubrication when installing the cannon pinion onto the center wheel? If so, what lubrication did you use?


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Discussion Starter · #3 ·
I did try some lube - Moebius 9104 without much difference. I also have 8200, 941 and 9010 if you think i should use instead. I do have one cannon pinion that works a little better. That is to say i can move it with the stem in the adjustment position but still seems a bit stiff. I guess in essence i just need to understand the relationship between the cannon pinion and the center wheel staff before i can begin to find cause of problem. Is there supposed to lubrication between CP and center wheel staff? Is there supposed to be friction to some degree?

The build i'm trying to get working properly....
Helmet Gas Font Circle Metal



A stripped down base plate i'm testing different cannon pinions on.....
Circle Font Metal Auto part Electric blue


reverse side of the test plate showing the center wheel installed. You'll notice that the bridge holding the center wheel in place only has one screw installed. This is because the other screw is broken off and I'm hoping to find some way to extract it. I have 2 of these base plates with screw broken in same place.

Font Circle Metal Art Pattern
 

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Discussion Starter · #4 ·
Was able to get it finished.
Titus Watch Co. Probably from the 50's
Some pics if anyone cares....
Brown Watch Analog watch Clock Measuring instrument


Watch Analog watch Clock Watch accessory Nickel
 

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Craftsman
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Nice watch. 9104 should work fine. I have used that on a number of my builds but have since reverted to 9501 grease. I theorize that the broken screw on the center wheel bridge is having an effect on the center wheel and allowing it to tip or bind as the cannon piñon is rotated via the motion works. How is the watch running on the time grapher now that you have it all together?

If the broke screw can be accessed from calendar side of the plate i.e. the thread hole goes all the way through the main plate, Bergeon makes a screw extraction tool that works very well for removing these type of screws. I have one and have used it on a number of occasions.
 

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Discussion Starter · #6 ·
That would be a good call except the plate you see there was my testing plate. The one used in the watch has both screws in place for the centerwheel bridge.
But speaking of these broken screws, as mentioned earlier, i have 2 of these plates with screws broken in same location and i would love to save them. I did check out the screw extractors from Bergoen as well as the cheap china versions on ebay. The broken screws measure .57mm and the screw extractors have bits down to .60mm so I wonder if they would work. the shaft of these screws are really tiny. Do you think one of these extractors have a chance of working?
 

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Craftsman
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If the broached extractor bits are too large they will eat into the threads in the hole and you will not be able to use a replacement screw of identical dimensions. Not sure what to tell you here.
 

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The cure can be worse than the problem here, as it takes practice to deal with this without smushing the threads in the plate. If you have a pointed carbide scribe, some light oil, and a binocular microscope, you can sometimes back the fragment out with very small CCW rotational movements. You need the microscope to see what motions are making progress and which are not. If you slip while doing this though, you run the risk of mushing the plate threads over the top of the fragment, preventing further progress. I sousing attempt this personally with just a loupe, as I know I am most likely to just make the situation worse.
Another approach is to soak the fragment out with warm alum or vinegar solution, but you have to remove all other steel parts in the plate (including any steel posts), and know that the plating may be damaged by the process.
 
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