This is a mainspring winder for small mainsprings. I’ve used it twice, once successfully, once not so. There are two shafts, marked R and L for winding direction. There is a small nub on the end of the shaft to hook the spring. One starts winding it by hand, turning the knurled knob at the opposite end of the shaft, while holding the spring flat against the disc end. When wound, the second knurled knob is turned that causes the bar to pivot pressing the end of the bar against the spring. If done carefully, the spring is held in place, under clamping pressure by the bar. If done not so carefully, the spring will launch itself into a good approximation of a golf ball. The first time I used it everything went well and I thought what a nifty little gadget. The second time wasn’t so good. This is the first time I’ve had it out of the box since.
Posts: 61 | Location: Cochranville, Pennsylvania USA | Registered: November 20, 2003