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Help reinstalling dial-side shock spring


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Here is the story folks. I was repairing a vintage ladies wristwatch and also making a video for my youtube channel. I did all the cleaning and was tackling the lower cap jewel. As i was removing the shock spring, I warned that they could easily fly out and be lost if you don't use a toothpick or some rodico and "PING"; it happened. So i looked for 30 min and nothing. Then went to all my scrap movements and everything was too big.  I then purchased 50 various shock springs from CousinsUK.com and only 1 of all the springs was small enough. The one I selected has three arms that would fall into the three indents and then you would have to rotate all three arms into the grooves.

My question is, with only two hands, how do I press all three arms down to rotate the shock spring and should I place a small line of rodico on top so I don't loone this one and only shock spring? I am working with a very high power stereo microscope so I can see everything. I have included the video I made so you can see the original shock spring but the new one is like a donut with three little arms.

https://youtu.be/VphPbKgTyvA

 

 

 

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There are actual tools from KIF for doing these, but what works just as well is pegwood. Trim a piece so that it fits in the setting, then dome the end concave with a round burr. Put the spring in place, press gently with the wood, and twist.

 

EDIT- ah now I see that it's not KIF. On these in my experience there is usually just one opening, do you have 3 there? If so, then the above technique should work. If just one, then slide one arm in with another over the opening, press it down and turn until the 3rd reaches the opening, press it down and turn 60 degrees.

Edited by nickelsilver
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6 minutes ago, nickelsilver said:

There are actual tools from KIF for doing these, but what works just as well is pegwood. Trim a piece so that it fits in the setting, then dome the end concave with a round burr. Put the spring in place, press gently with the wood, and twist.

 

EDIT- ah now I see that it's not KIF. On these in my experience there is usually just one opening, do you have 3 there? If so, then the above technique should work. If just one, then slide one arm in with another over the opening, press it down and turn until the 3rd reaches the opening, press it down and turn 60 degrees.

Hey, that is an excellent tip, i will try.  There are 3 openings so all three arms need to go in at the same time. getting out my knife right now:)  Will need to find a small round burr.

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If you don' have a burr, but have a lathe, you can use a drill bit to create the concave end detail.

Doing it by hand won't work well, but you could try some tubing over the drill bit as a guide for the wood, in a vice (point up) and place the wood into the tubing and rotate by hand until you have a concave on the end.

Once the center is done, place the stick in the pencil sharpener and gently reduce the OD until it's right. This should work OK for you.

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I had a similar problem a couple of weeks ago. I believe this type of shock system is called Novodiac.

I used 2 tweezers, 1 in each hand, and keeping the jaws of 1 of them slightly apart to press down on 2 of the arms simultaneously while the other tweezer presses down the last arm and turning the shock spring into locking position. It took me 45 minutes to accomplish that.

I spoke to my mentor the next day and he also mentioned using pegwood with a hollowed tip. He also said that a brass tube, like that from a broken spring bar, also works.

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