Originally Posted by
mparker326
Thanks for the good advice.
It was mentioned on here that filing should be the exception. I never had to file until I came across a Peugeot cottered crank. Original cotters were the "Peugeot" cut as mentioned on the
Bikesmith site.
My LBS only had half cut French cotters. So I figured I would try my hand at filing. It was a terrible experience and I ended up converting it to a three piece crank. I acquired another bike with a unique BB that requires only a single cotter so conversion is not an option.
I avoid filing by replacing with matched pairs of cotters, but this doesn't seem to be an option for you.
Clamping in a vise and filing flush to the tops of the jaws assures a flat wedge area.
Your problem won't be filing, it'll be determining and duplicating the angle you need. You might do this trial and error, by estimating the angle, and filing it steeper (short wedge area) then testing the angle. Then you can make it longer and shallower by degrees until the angle is right, and finally using a guide or the magnet-and-shim technique to clamp it higher and file the same angle to the right depth.
FWIW- the depth isn't critical as long as it's within the range that allows the nut to thread on properly, yet not so deep that you run out of thread.