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Cannon Pinion on Gustav Becker

MJShaw

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Jan 3, 2021
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I am new to clock repairing and I'm working on a Gustav Becker clock & would appreciate some advice.

What does the "P64" and other markings on the clock tell of its age?

The clock is not chiming and I don't know why so I decided to investigate the mechanism. Does the GB mechanism have a chime silent lever?

After removing the hands and face and now reassembling it, I have found the cannon pinion is loose on the shaft. Turning the minute hand does not move the cannon pinion and so there is no movement of the hour hand as the minute hand is rotated.

The hour hand was quite tight on the hour wheel so I am concerned the cannon pinion may have become loose getting the hand off. The cannon pinion looks to be a solid brass pinion with two lugs on it and there does not appear to be a means to tighten it to the shaft.


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shutterbug

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Can you see slipping where the minute and hour wheel connect? If the minute hand is very loose, it might potentially spin without moving the hour hand. We need to narrow this down a bit, so please observe what you can see slipping and let us know. Pictures of the offending part will help too. We need to know what exactly is slipping in order to advise properly.
 

MJShaw

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Jan 3, 2021
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The cannon pinion is loose on the center shaft. I think it should press onto the shoulder on the shaft and be fixed. Is it common practice to apply a glue or locktite to this pinion to prevent it coming loose? cannon.jpg
 

shutterbug

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LocTite 609 (I think that's the number) would probably be strong enough to hold it. It's not the "Proper" approach to the problem though, and the next guy will have a devil of a time getting it off unless he knows what you did :) Metal bonding agents have really been improved in recent years, and are commonly used in manufacturing. We see their use more and more in clock repair too ... much to the chagrin of many of us ... but it's a reality that we have to accept - that "easy" fixes like that actually do work :)
Be sure you have a minute hand with a bushing. Otherwise you'll have to position the star precisely.
The best approach would be to knurl the arbor and put the gear back in place with a friction fit.
 
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