Internet Horology Club 185
Mainspring centering

This topic can be found at:
https://ihc185.infopop.cc/eve/forums/a/tpc/f/3426047761/m/2093928787

June 05, 2016, 18:02
Michael Webley
Mainspring centering
Hello all,
I peruse the club website almost every day but I don't post much at all, the reason being that until recently I had a wonderful go-to person,(Paul D. Trombley, lived 5 mins. from me) who was always available and answered all my questions but is now, sadly, deceased. So now I have to pose my questions to anyone else who has the time and / or the inclination to offer advice (always graciously accepted.
My question is this:- how does one bend the inner curve of a (pocket watch) mainspring to center it over the center of the barrel, without snapping it.....heat ?

Thanks, Mike
June 05, 2016, 19:31
Steven Ford
Mike,
I don't know if it's correct, but I'll tell you what I do, I don't try to center it..
First, if the spring has not been broken, the end usually is not hardened near the end and can be formed to hold to the hub tight enough to not slip off.
Next, put the hub in and push it to the center, it doesn't have far to go. Once you have wound it a turn or two, the rest of the spring holds it centered. If the watch is being used, it seldom runs to the end of the spring anyway.
It's always worked for me.

If the spring has been broken then yes heat would be the only way to rework the end, but a new spring is a much better way to go.

Lets see what the pros say!

Steve
June 05, 2016, 20:21
Michael Webley
Thanks for your advice Steve. From the pros...we wait with baited breath.

Mike
June 08, 2016, 13:39
Rafal Woler
Here you have some insight about manipulation of hairspring:
https://www.youtube.com/watch?v=idO5elKgFMA

Maybe you will find something useful. I recommend whole channel to watch.
June 08, 2016, 16:06
Steven Ford
Thanks, Rafal!
Looks like good info.

Steve