Summary for rust wrought iron Discussion
Rust wrought iron is not as simple as letting it sit outside, because the thread explains that natural rust on steel or iron is fluffy, non-adherent, and water-absorbing, so it tends to rub off and keep spreading. The questioner, Connie M., wanted an authentic rust finish rather than rust-colored paint. The answer notes that a black oxide coating is possible, similar to a rifle barrel finish, but it would likely need to be outsourced and kept lightly oiled, and it would not hold up well outdoors or in harsh conditions. The main challenge is not making rust appear, but making it stay put. The reply says a clear coat is usually needed after rusting, but it must penetrate to sound metal; otherwise the rust and clear coat will flake off together. The answer also suggests searching the archive for longer related discussions.
Q. Please tell me how to rust wrought iron, for an authentic rust finish, I do not want a rust colored paint.
Connie M [surname deleted for privacy by Editor]
– Giddings, Texas
2003
A. The specific application will matter, Connie. It is possible to do a “black oxide” coating, which is similar to what you would see on a rifle barrel, although you’d probably have to send it out. But this must be kept lightly oiled, and it won’t hold up outdoors or in a difficult environment.
It’s easy enough to get cast iron to rust, but how are you going to stop it, and how are you going to keep the rust from rubbing off and getting onto everything? The basic problem is that a natural rust on steel or iron is a fluffy, non-adherent, water-absorbing surface. To stop it, you generally have to apply a clear coat after it, but the clear coat has to reach through the rust to sound metal, or the clear coat and rust will just flake off together.
Good luck, and please spend some patient time with the search engine because we have long and interesting threads on this subject.
