Vibrating an Elinvar hairspring
Hairspring vibrating tools are very cool looking, and useful, and I don't have one. But I improvised with a sliding clamp (a piece of wire) around tweezers and a bench block. Comparing the motion of the balance to the tick of my trusty Elgin made quick work of finding the right length of this NOS Elinvar (Hamilton 992) hairspring.
For the pinning at the center (I made the new collet too) I used the modern scheme of just straightening the inner coil and gluing it into a slot in the collet. Although I think most manufacturers use an epoxy for this application, Elgin recommended shellac if anyone ever needed to repin a hairspring on a Durabalance. It seems to hold fine and I recommend it.
(Click for a bigger image)