Might need softer copper washers................
Which comes back to the need to anneal those suckers. I do as suggested above with a propane torch, only after they change color I drop them off the wire into a cup of room temperature water. They also need to be flat on both sides. File any big stuff off, then emery paper on a piece of glass. Sand until they are bright all the way across, on both sides. Clean, and install.
