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Pinning the hairspring to the stud


fuse63

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11 minutes ago, jdrichard said:

Perhaps just holding the stud in place with a small screw would be easier? Holes can be round:)


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That would work too, but would require more accurate tooling than I have access to. I've always found it hard to drill two intersecting holes accurately (such as a set-screw in a shaft linkage or the like). Plus the size of the set screw would likely be quite small (like the on the balance arm), anything much larger would risk damaging the stud. But hey, anything is worth a try!

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I think Clockboy had the answer a few posts ago. I’ve  only done this a few times, but what he describes works ok... and you may find that you spend much longer making a tool than you will save versus doing it this way.

If you secure the stud in the balance cock with the hole just above the cock then you can hold the cock on some rodico and you have as much of a tool as you should need to keep the spring square while you pin it. The hairspring should be removed from the balance. Once you have pinned the spring reasonably securely to the stud so it won’t move you should check the timing before pushing the pin home. You will also need to check that the spring sits between the regulator pins without the collet centre moving away from the jewel hole throughout the range of movement of the regulator. I’m sure Mark has a video on this, but I wouldn’t start trying to adjust the spring without being sure it’s pinned in the right place.

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2 minutes ago, StuartBaker104 said:

I think Clockboy had the answer a few posts ago. I’ve  only done this a few times, but what he describes works ok... and you may find that you spend much longer making a tool than you will save versus doing it this way.

If you secure the stud in the balance cock with the hole just above the cock then you can hold the cock on some rodico and you have as much of a tool as you should need to keep the spring square while you pin it. The hairspring should be removed from the balance. Once you have pinned the spring reasonably securely to the stud so it won’t move you should check the timing before pushing the pin home. You will also need to check that the spring sits between the regulator pins without the collet centre moving away from the jewel hole throughout the range of movement of the regulator. I’m sure Mark has a video on this, but I wouldn’t start trying to adjust the spring without being sure it’s pinned in the right place.

But making tools is FUN!!!! (insert sarcasm here)......I agree it would work that way, it just wouldn't be as stable of a platform as the tool. If you're just re-pinning the hairspring due to a lost pin, then it should just pin back in the same place as the original. Otherwise timing (vibrating) the spring would be necessary yes....

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But making tools is FUN!!!! (insert sarcasm here)......I agree it would work that way, it just wouldn't be as stable of a platform as the tool. If you're just re-pinning the hairspring due to a lost pin, then it should just pin back in the same place as the original. Otherwise timing (vibrating) the spring would be necessary yes....

I could just use the balance cock to hold the stud???!


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If it came out it has to go back in, I wouldn't try narrowing the spring or messing with the stud....spring goes on the inside of the stud hole closest to the balance staff, brass pin goes on the outside of the spring 

I broached the hole a bit and got the spring in.


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