Up here in the soggy Pacific NW, we don't have to shovel snow very often but we
do have lots of problems with moss on our roofs. I was out spraying Moss-Out on
my roof just now, which takes awhile, and it got me to wondering. That stuff is
basically about as much zinc as they can dissolve into water without including
anything too dangerous. And of course zinc in solution will reduce iron oxide to
iron. So I'm thinking if I had something small and precision that had rusted I'd
try just soaking the item in moss killer, might just make it shiny and clean ..
if so, that would be another trick.

Let's see, our bag of tricks include:

sandblasting
power wire brushing
pneumatic needle gun
naval jelly
vinegar and salt
various acid soaks followed by neutralizing basic soak followed by hot water
electrolytic derusting
soaking in strong solution of molasses
soaking in solution of zinc in lye
and, maybe, soaking in moss killer

did I forget any?

GWE