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What shape should this hairspring be ?


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I've just finished cleaning this Smiths Imperial 19J , and all sorts of weird things were happening when trying to set the timing.  Initially the hairspring was pushing on the outer regulator pin, so when I moved the regulator it took the spring with it. I tweaked it so that it just sits near the inner pin, but under the microscope it's clear than the final curve of the spring is wrong. 

Should it just follow the red circle up to about the red arrow, then have a kink out to the stud ?

 

 

 

Smiths Imperial 19J.jpg

Smiths Imperial 19J_2.jpg

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Just checked a couple of my Smiths Astrals & there is no kink in either spring, they appear the same as yours & run fine. Have you demagnetised or is the spring in need of further degreasing?

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9 hours ago, Blacklab said:

Just checked a couple of my Smiths Astrals & there is no kink in either spring, they appear the same as yours & run fine. Have you demagnetised or is the spring in need of further degreasing?

Thanks that's useful info and saved me possibly messing up the spring. I do need to tweek it a bit as it doesn't follow an arc near the pins. 

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That’s how most English Smiths are (without a link to provide a constant termination radius). I’d be tempted to leave it as-is unless you are good at hairspring manipulation. 

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