This completely sucks. I am replacing brake cables for the first time on one of my bikes, and I noticed some corrosion in the inside of a cable-stop (the part of the stop which the ferrule contacts). Due to the small amount of corrosion (it's white colored, not rust colored), a new ferrule won't fit into the stop. What types of metal are cable-stops typically made out of? Is there some chemical I can use to eat away the corrosion, or should I try to somehow sand it out? If I'm going to sand it out a bit, I wonder how I'm going to get some abrasive object into the small diameter of the stop.
Any suggestions would be appreciated.