So ive got my barrel and ive burned all the paint off and sanded the inside and outside then primered the outside. The inside was cleaned out with mineral spirits, dryed then wiped down with canola oil. I dont think I coated it enough with oil because im getting spots where its rusting again. My question is, is that rust ok or do I need to sand it down again? Heres a few pics of the build so far. But dont have any of the rust on the inside yet.