Might be a little crude but it seemed easier than replacing the entire dropout. I cut and filed off the broken piece so it was parallel with the horizontal dropout slot, then cut off the same part from a donor frame, cutting it so it matched the entire piece of metal removed, eyeballed the alignment, held it in place with vice gripes and brazed it on. Cleaned it up(marginally) will a little filing and done. Its plenty strong for the load the derailleur puts on it. Surprisingly it didn't need any alignment, but an adjustable open end could have easily done it. Frame is a 85' Pug urban express, a freebie because of the broken dropout, now a city/grocery bike for a friend.