# Hour and minute hand have stopped moving, second hand works fine



## matt1415

So I'm dealing with an odd situation here. Im working on an old watch called a Norby, its just a basic mechanical sub dial watch from the 30's. So the hands moved fine when I first got it but now they seem to not be engaging. The problem started after the crown and stem fell out upon setting the watch. The stem was an easy fix it went right back in and I tightened the screw. After that it set fine and wound normally but only the second hand on the sub dial would move. Also the hour and minute hand seem to move really freely if touched. The watch was not dropped or anything so I'm really clueless as to what is going on. 

Thanks for any help in advance


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## pithy

Cannon pinion.


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## matt1415

pithy said:


> Cannon pinion.


Had a feeling that might be it but wouldn't that prevent the hands from moving even in the setting position?


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## GeneJockey

matt1415 said:


> Had a feeling that might be it but wouldn't that prevent the hands from moving even in the setting position?


Nah. If the second hand still runs but the hour and minute don't, the cannon pinion is loose on the center arbor. Insufficient friction to drive the hands. In the setting position, the stem is directly connected to the cannon pinion, so it will turn the hands.

Sometimes, if your cannon pinion is loose but the hands have been turning, then stop it could be they're stuck, on each other, or on an hour marker, or even dragging on the crystal.


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## Michael Maddan

matt1415...if it turns out to be a loose cannon pinion, do be very careful when tightening it: some are made of steel that seems a bit brittle--others, don't mind being tightened. Always use a rather close-fitting (brass) rod passed through: as the tightening occurs, the brass rod will keep the pinion from cracking.

Canon pinions should be a very snug (for want of a better word...) fit...they should come off without any real effort, and go on the same way. I always use just a light film of, say, Moebius 9020 on the center arbor prior to installation...it prevents the cannon pinion from 'seizing', yet allows sufficient friction. Michael.


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## matt1415

Michael Maddan said:


> matt1415...if it turns out to be a loose cannon pinion, do be very careful when tightening it: some are made of steel that seems a bit brittle--others, don't mind being tightened. Always use a rather close-fitting (brass) rod passed through: as the tightening occurs, the brass rod will keep the pinion from cracking.
> 
> Canon pinions should be a very snug (for want of a better word...) fit...they should come off without any real effort, and go on the same way. I always use just a light film of, say, Moebius 9020 on the center arbor prior to installation...it prevents the cannon pinion from 'seizing', yet allows sufficient friction. Michael.


Loose cannon pinion it is. I removed the dial and cleaned everything underneath but still the same problem. I don't feel comfortable with tightening the pinion but I'm afraid that may be the only solution. Hypothetically would a small drop of uv glue help keep that pinion in place?


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## matt1415

Forgot to mention the hands now move but really slowly.


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## Joe Horner

Please, NO to any sort of glue or other gunging-up!

It would carry at least 4 risks, in order of seriousness:

(1) not working effectively

(2) as the pinion slides creating dried glue dust to spread through the movement

(3) seizing the pinion and causing damage when the hands are set

(4) earning the undying scorn and disapproval of whoever works on it next.

Tightening them isn't difficult, it just needs a gentle touch and patience - better to take several attempts that don't tighten it enough than one that goes too far.


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## matt1415

Joe Horner said:


> Please, NO to any sort of glue or other gunging-up!
> 
> It would carry at least 4 risks, in order of seriousness:
> 
> (1) not working effectively
> 
> (2) as the pinion slides creating dried glue dust to spread through the movement
> 
> (3) seizing the pinion and causing damage when the hands are set
> 
> (4) earning the undying scorn and disapproval of whoever works on it next.
> 
> Tightening them isn't difficult, it just needs a gentle touch and patience - better to take several attempts that don't tighten it enough than one that goes too far.


Haha, like I said hypothetically. Sorry I know that idea was a bit out there but I'd love not to have to remove the dial again. It's old enamel and I'm scared to death of putting a mark on it. So how exactly is the the cannon pinion tightened? You and Michael both gave great explanations but with what tool? I was thinking pliers to squeeze the pinion or a crimp tool.


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## GeneJockey

Depends on the cannon pinion. There's a good section on this in Fried's 'Watch Repairer's Manual'. It's really a matter of very slight changes. In the case of the ones with a dent, it's the V-block and the center punch in a staking tool. You absolutely need to have some close-fitting pin or such inside to prevent crushing.


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## matt1415

ok so as you can see have removed both pinions. Do each of these need to be tightened or just one?


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## GeneJockey

Only the cannon pinion. The big one isn't a pinion, it's the hour wheel.

In order for the hands to move, the center wheel arbor has to drive the cannon pinion, which is the one that fits over it, so that has to be tight.

In order for the hour hand to move at a different rate from the minute hand, the hour wheel must be able to spin at a different rate from the cannon pinion, so it has to be loose.


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## matt1415

GeneJockey said:


> Only the cannon pinion. The big one isn't a pinion, it's the hour wheel.
> 
> In order for the hands to move, the center wheel arbor has to drive the cannon pinion, which is the one that fits over it, so that has to be tight.
> 
> In order for the hour hand to move at a different rate from the minute hand, the hour wheel must be able to spin at a different rate from the cannon pinion, so it has to be loose.


Awesome thanks for the explanation I knew I was missing something


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## Roland Ranfft

Hi matt1415,

I followed this thread only because it is so heartwarning, how all try to explain that it is a watch you are cluelessly tinkering on, and not a bicycle. And obviously with every post your chance to finally ruine your watch grows.

Anyway, with your pic you provided the first fairly useful infomation about your watch movement:
It is a Roskopf-type movement (likely a Baumgartner 666), and disregarding which tube you tighten, it will reliably stop the motion of the hands forever, and degrade the watch to a tick-noise generator.

The characteristic of a Roskopf is that the cannon pinion runs idle on a fixed center post, and friction between train and hands gear is done with a minute wheel on the barrel, which is friction coupled to it. I.e. you need to remove the barrel-wheel assembly, look how the friction clutch is designed, and tighten it accordingly.

However, after having followed this thread, the best chance for your watch is to leave it to a watchmaker, or at least to a hobbyist, who knows what he's doing. It is like with all technical thingies: To repair them.one should have a faint idea how they work.

Regards, Roland Ranfft


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## GeneJockey

This is why pictures are worth a thousand words. Think how many we could have saved if the picture were in the first post.


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## Joe Horner

Yep, the pic does change things slightly 

The fundamental principle's the same, though. Find the friction drive, see how it works, and work out how to tighten it.


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## matt1415

I'm going to disassemble the whole movment and give it a good clean. Haven't done anything drastic to it yet so it can probably still be saved.


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## matt1415

Update: reassembly and cleaning was successful. She's alive again and working! Thank you everyone for sharing your knowledge and insight with me. It is greatly appreciated


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