How do I remove rust?

An usefull article regarding rust removal and protection

In article <N.090696.183321.48@rtd2-16.worldaccess.nl>
rbezemer@worldaccess.nl (Roland P. Bezemer) writes:

31.15 How do I remove rust?
It depends on the sample and amount of rust. If the material is heavily rusted, then physical techniques ( sand blasting ) may be appropriate.
 

Chemical techniques on steel usually involve phosphoric acid, and the concentration depends whether the treatment can be washed off. An
excellent discussion is available in Product Finishing [25], along with
simple formulations. For removing light rust without subsequent removal
of the solution, 15% H3PO4 + 4% nC4OH + <0.1% H2SO4 is used, but if the solution can be washed away, then 33% H3PO4 + 2% nC4OH is preferred.

My question is: What is nC4OH?

n-butyl alcohol, I'll change the FAQ - I thought that nomenclature
was fairly common - obviously not.

A secondary question is: has someone tried this recipe, and if so did it work on steel (especially rusted 316 stainless)?

I use it routinely on mild steel and cleaning up rusty steel.
It's especially good if you have old files ( metal-working
type, not administration ones - although come to think.....)
Zap them with 1:1 aqueous hydrochloric acid to clean and
sharpen them, immediately water rinsed, and followed by
the above to put a coating on that slows onset of rust.

The formula should also work on stainless, but I've never tried.