Junghans A12 fly pinion repair

eemoore

Registered User
Apr 26, 2008
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I am repairing a Junghans A12 movement and the fly pinion is damaged.It is a 7 leaf pinion and I need a replacement or repair. Is it possible to repair the pinion , and how is this done? Also is it totally necessary to have a fly inorder for the strike to correctly work. I am new to this so I appreciate any suggestions. I have tried to find a replacement arbor and pinion but no luck so far. Thanks for any suggestions. IMG_2735 2.jpeg IMG_2735 2.jpeg
 

Willie X

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Feb 9, 2008
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eem,

Try searching 'pinion repair' and yes this is a routine 'thing to do' in clock repair.

Also, yes the strike train has to have a fly. It acts as both a governor and to cushion the shock every time the train is abruptly stopped.

Willie X
 

shutterbug

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This will be a fairly easy repair. Do a search for "lantern pinion repair".
 

eemoore

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Apr 26, 2008
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What is actually wrong with the lantern pinion? It appears that it is missing one trundle wire.
One of the wires(leaf) in the pinion has broken and I am trying to fix it. Some other members ave referred me to search for "repairing pinions" so I am going to try that. Thanks very much for your help and consideration.
 

eemoore

Registered User
Apr 26, 2008
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eem,

Try searching 'pinion repair' and yes this is a routine 'thing to do' in clock repair.

Also, yes the strike train has to have a fly. It acts as both a governor and to cushion the shock every time the train is abruptly stopped.

Willie X
Thanks so much for the info. I will try to research this out. I am an old man trying to learn a new hobby! Thanks again.
 

eemoore

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Apr 26, 2008
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What is actually wrong with the lantern pinion? It appears that it is missing one trundle wire.
Yes thank you again. I now understand that the little wires are also call " trundle wires". I have gotten the old broken trundle out so now I am going to try to replace it with a new one. Any suggestions are appreciated.
 

Vernon

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Measure the original wire diameter with a caliper then buy music wire, some hobby stores may sell this. Cut it to length with a diamond cutting disc using a Dremel and smooth the ends. Support the shroud so that it doesn't move while you close the hole over the new wire by gently pushing brass using a small tool, try to match the others. You may need to open up the hole for the new wire using a small drill (finger powered), especially if the old one didn't come out that way.
 
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Willie X

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You may get lucky and find a guitar string (or piano wire) that's just the right size. But to know what is "the right size" you will need some type of caliper for measuring.

If you don't already have the tools, by far the best thing would be to take it to a clock repair shop. They will probably do this at a reasonable price and possibly while you wait, if you are at a long distance. There are also reputable places where you can send it out for repair.

Good luck,. Willie X
 
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eemoore

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Apr 26, 2008
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Many thanks to the members who responded to this post. I was able to measure the trundle wire, order the correct size, and install it. The strike train works well now. I just have to figure our why the clock will not run. Something seems off with the verge, and crutch and pendulum alignment . Trying to figure out how to adjust the crutch correctly. Thanks again for the help. IMG_2740.jpeg IMG_2739.jpeg IMG_2738.jpeg
 

Vernon

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Check the suspension spring mountings (both ends) for any movement of the spring where it is affixed. It looks a little loose in your photo.
 

JimmyOz

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The leader is hitting the back of the crutch in your photo #1, slightly bend the crutch inward so the leader is not rubbing on it, it needs to hang free.
 

eemoore

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Apr 26, 2008
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Check the suspension spring mountings (both ends) for any movement of the spring where it is affixed. It looks a little loose in your photo.
Thanks for the info. I was thinking about getting a new suspension spring if I can find a match,. does it have to be exactly like the original? thanks again.
 

eemoore

Registered User
Apr 26, 2008
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Check the suspension spring mountings (both ends) for any movement of the spring where it is affixed. It looks a little loose in your photo.
Thank you. i will try to make the adjustment. I appreciate your reply.
 

bangster

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What bikerguy said. And remember: this Message Board will see you through. :thumb:
 
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Vernon

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I was thinking about getting a new suspension spring if I can find a match,. does it have to be exactly like the original?
That's what I would strive for. Does your spring have damage?
 

Vernon

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oops!
 

Vernon

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I just noticed, it looks like the teeth on the ew. are bent over. Those will need straightened using a smooth jawed plyer and working from the root of the tooth, lightly follow the straight portion of the tooth while sliding the plyer to the end. It might take one or two strokes for each tooth.
 

eemoore

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Apr 26, 2008
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I just noticed, it looks like the teeth on the ew. are bent over. Those will need straightened using a smooth jawed plyer and working from the root of the tooth, lightly follow the straight portion of the tooth while sliding the plyer to the end. It might take one or two strokes for each tooth.
thanks for your help. I will try to correct the teeth, The help on this forum is great. Really nice members .Thanks again .
 

eemoore

Registered User
Apr 26, 2008
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I just wanted thank everyone for their recommendations, as seen above . I was able to tighten the spring, straighten the leader, make some adjustments to the strike train, fix the pinion and now this old clock is running like new! I still have to finds some hands to fit, but that's no big deal. Thanks to all . I love this forum!
 

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