bob2 posted:In the olden days, benzene would have done it.
Benzene would likely take the paint off and I doubt that many can get hold of any anyway being a defined carcinogen. Real mineral spirits won't leave a film; comprised of relatively low MW aliphatics; WD-40 is designed to leave a film as a water dispersal agent. A detergent might work as long as it's not a caustic one.
Good luck.