Reply To: Sizing a mainspring

[Bob Tascione]

Hi KyBill,
There are a couple of good books available to help identify American movements. The one I use most is “The Illustrated Manual of American Watch Movements” by Swigart Co.” I might be able to help identify it for you if you post a pic up here. Also the serial number may help. You put a pic of it in another post but that was the dial side only.
We may be able to nail down which mainspring you will need.
Bob