Reply to "Are Postwar Lionel aluminum passenger cars anodized?"

An easy way to test to see if  cars are anodized is to take a amp/ohm meter and check to see if the car body is conductive. Anodize is non conductive. When checking make sure that you  do not use the pointed tip of the probes but rather the sides of the probes as the pointed tips can penetrate thru the anodize. Cape Cod Polishing Cloths are another good product for cleaning aluminum. The alloy is most likely a 6000 series aluminum as this is commonly used on extrusions. 6000 series such as 6061 or 6063 have a small amount of silicon and magnesium mixed into the alloy. You need to take that into consideration when attempting to clean.