BITD one of the shop tools from the cottered crank era was a cotter holder, so you could clamp it in your bench vise,
in the holder, an take out a file, and file the taper to have a perfect fit..
tap on it with a hammer then slug up the but , don't try pulling it tighter with the nut, use a hammer on the other end..
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Last edited by fietsbob; 08-25-20 at 07:11 PM.