Re: Seamster gaining time quickly
I wonder whether the hairspring may have snagged on something perhaps due to shock or some debris getting lodged in it. That would effectively increase the spring stiffness which would increase the natural frequency of the balance wheel considerably. I can't think how else it could speed up. If that is the problem then it may be very easy to repair without having to replace parts. Let's hope so. I'd expect any other mechanical problem to cause it to run slow or stop altogether, but I'm not a watchmaker, just an engineer.