RE: Home Brew After-Run Oil
Actually there is Marvel Magic Oil and there is Marvel Magic Air Tool Oil (ATO). The latter is much more expensive, but I don't have any idea why. I think the idea of ATO is both lubrication and protection from the water that is likely in the air line from the compressor. Whether the ATO takes the water into solution or just isolates the metal parts from it is a "Mystery" to me. I use the ATO in my air tools, but I just use Dextron ATF in all my engines for an ARO with very good results.