I was cleaning up some switches earlier today with the intent of eventually putting them on my layout. They're Marx O34 switches, which are nearly as hard to find as true love, so I had to take what I could get. Some Marx O34s are in far less than pristine condition when you find them. One was just really dirty but the other had some surface rust. So I broke out the Bar Keeper's Friend (you can buy it almost anywhere that sells cleaning supplies, and it's usually right next to the Comet). I poured some into a plastic lid, added a little water to make a paste, dipped in a rag, and started scrubbing. Off came lots of dirt, tarnish, and even the rust, with a lot less scrubbing than you would imagine. I just did the tops of the rails, since that's what matters most. Then I set them up on a loop of track on the floor and tried them out. My transformer indicated a short. :curse: I narrowed it down to one of the switches. :curse: :cry: :curse: So I took off the cover and looked around. Finally I found a loose wire that was supposed to be connected to a light socket. I fixed that, then the switch worked fine. And my test locomotive ran just as fine on my rehabbed 50-year-old switches as it did on the new track that was in the loop. Nice. You gotta love something that's a cleaner, polish, and rust remover all in one and comes in a can that costs about three bucks.