As long as there is moisture in some form and iron atoms awaiting a bond, rust will form (Mars is a great example, on a very large scale). The Test Module lung was not designed to last for three decades, as the shell over top was not water tight and the pan beneath suffered from heavy rust. The SAM team has spent a great deal of time grinding, sanding, priming, painting, and sealing this structure over the past year in order that it might continue to provide an internal, positive pressure to SAM.
Volunteers Luna Powell and Elie Danziger removed the last bits of loose rust on the upper lung pan. This involved a pass with steel scrapers and sixty grit paper on an orbital sander. They then applied a coat of Rust-Oleum direct-to-rust primer before the final enamel will bring this historic structure back to life.
The Rust-Oleum primer has proved itself time and again at SAM as a go-to solution for otherwise challenging, heavily rusted steel. While it is an oil base, it has almost no odor after just 24 hours curing and can be top-coated with oil or water base paints (which is unusual). What’s more, the back of the can has an 800 phone number that is answered by a real, live human who actually knows what he or she is talking about! If only all products had this kind of support. (No, Rust-Oleum did not sponsor this post, but they should!)
