my method of repairing lamp sockets is to use a points file. scratch clean an area of the bottom of the socket and the strap where they touch. bridge the cleaned gap with solder. next scratch clean the oxidation off of the center post, solder a drop of solder on it, solder one end of a 1.5 inch piece of de-soldering braid to it, and wrap the other end of the braid around the connection post and solder. lift the center of the braid up and away from the strap to avoid shorts.