How to remove Rust on Stainless Steel?

[Vasco]

I know Spotless Stainless passivates the stainless. Don't know if any of the other methods which involve oxalic acid and scrubbing does.

[gjordan]

OSPHO(brand name)(phosphoric acid) works wonders at getting rust of off anything, but should be rinsed very well from stainless steel. Polish with any normal SS polish after the Ospho treatment.__worked well for me with Taiwan SS.____Grant.

[daddle]

The science is that one wants to remove the iron oxide (rust) from the stainless steel without removing the chromium and iron. Acids tend to be too aggressive. Most will etch the surface leaving it dull. The popular stainless polishing compounds use a different chemistry to dissolve the rust.

If the chromium at the surface is removed with acid or sanding or abrasive cleaners then what remains will be chromium. And exposed iron. The iron will rust. This begins an endless cycle of aggressive cleaning. What is needed is passivation - which is a fancy word for dissolving the iron to leave only passive chromium at the surface. At a factory they will use a carefully controlled acid wash and polishing regime.

For us, the best way is one of the many stainless polishing pastes. They are designed to remove the surface iron (the cloth turns black) and leave polished chromium behind.

Rinse and air dry for a few days is important. Waxes are a bad idea except just before the boat show.

[s/v Jedi]

I recommend to take the fittings off the mast and have them electro-polished. I know it has the best results by far, and I also believe that in your case it's worth the effort.

cheers,
Nick.