Lift angle

Submitted by JermR82 on

I would like to know if anyone know the lift angle for 10AN and 10AX. I've searched online with no luck. Thank you. 

mybulova_admin
Posted January 30, 2026 - 2:21am

I've been repairing 10ANs for a very long time, so excuse my ingnorance.....what's a 'lift angle'?

JermR82
Posted January 30, 2026 - 4:16am

In reply to by mybulova_admin

You've been repairing them not knowing what lift angle is? How can you accurately repair them without knowing the lift angle?

lift angle is the specific number of degrees the balance wheel rotates while the impulse jewel is in contact with the pallet fork. It is a critical setting for a timegrapher to accurately measure a watch's amplitude and overall performance. 

mybulova_admin
Posted January 30, 2026 - 8:21pm

In reply to by JermR82

I don't go down to that level of repair and I've really never needed to when I work on my watches. 9 times out of 10 I must get lucky with the lift angle as I really ever have an issue when restoring or repairing. I've worked on possibly 50+ 10AN movement in the last 20 years.

I'm sure if you have the skill and knowledge it will help, but for me it's something I've never been concerned with.

So how do you adjust the lift angle of the balance wheel?