I am looking to source a pocket watch main spring so that I can replace some of the broken springs on a 7912. Has anyone done this and can they kindly advise as to what dia, main spring I should be going for (any other tips re. replacement welcome). I have no issue with taking the stretch links apart, and yes, I am aware that a guy in Hong Kong replaces springs at reasonable cost.

Thanks in advance!

 

I've had some success using hard rubber sponge to replace the springs in 1039 bracelets .
Maybe it would work with the 7912.
The small pads that glaziers use to protect units in transit are ideal.

 

I might be able to supply some springs, Ive got a load of BCT bits so PM me, depends how many you need