Originally Posted by
surreal
You cannot wrench a cottered crank righteously without sufficient means to properly remove and reinstall cotter pins; I, for one, don't really wanna buy that press.
.
Long before the late sixties when cotterless cranks went mainstream, the majority of bike mechanics in the world routinely worked on them using hammers to remove or replace the cotters. In many cases we could remove a pin without damaging the thread by backing the nut out about 1/16" or so.
The lost secret is to properly support the crank, so the energy of the hammer blow couldn't be dissipated by the crank rolling with the punch. Supporting the crank also isolated it so there wouldn't be any damage to the bearings,