Yes / no questions

Once "stainless" steel is -- not severely -- rusted by atmospheric humidity, if it's taken to be nickel plated, will the nickel cover the rust?

If so, my second question would be... What will happen to this rust? -- will it remain or expand within the nickel layer.

Would distilled water rust even the lowest-standards of stainless steels?

Thanks a lot for those who can answer these elemental questions.

How do you figure that "What will happen to this rust?" can have a yes/no answer, Alberto? :-)

1. Yes. The process of nickel plating will always include a rust removal step. If the part is not severely rusted, things should be okay. If the part is pitted with rust, the pits will still be there and the plating will most likely be unsatisfactory.

2. The rust is dissolved away before the plating occurs.

Yes.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

I've been doing some research on the rust removal techniques for I'm trying to do this myself. The lucky metal belongs to a thirty-year old Japanese bike.
By any chance, is the technique you are referring to an electrolytic process? If so, when can one be certain that the rust has been removed/(transformed into iron?) do the bubbles mean anything in this case?
Finally, can nickel be plated on the black stuff that replaces the rust on these pieces in such a way as to resist high mechanical pressures and impacts? (assuming that the plating process will be most appropriate to reach such hardness)

Thanks for your help and Merry new year to all.