What is the best metal polish to use on the Nickel Rimmed Drivers and side rods on the 2020 and 675 Lionel Postwar Steamers. I don’t want to use just any metal polish that would harm these Postwar Beauties.
I have used Flitz polish on the rods, and am pretty satisfied with it. It seems to give a higher shine than chrome polish. However, it won’t remove rust. Also, it takes some elbow grease to get a really high shine on a really dull piece, but it sure looks nice 
I’ve never felt the need to polish the nickel tires, tho.
I am having trouble with a 1952 era 2025 , tho. Polished up the rods, and they became dull as dull again after about 6 weeks exposure to the air. I’m guessing this might be the fault of the rods (diffferent plating used due to the Korean War?) rather than the polish, since it is only this one loco doing it. Going to try again with Flitz plus Turtle Wax and see if that does it.
I don’t know what the “best” might be, but that’s what I’m using now.
I have used both Never Dull and Mother’s Mag & Aluminum Polish with great results. Never Dull is also great at removing stubborn carbon from commutators without scratching.