Marc wrote:
> Then I purchased a gallon of Evapo-Rust, dumped it in the tank, and left
> it to sit over night. Checked it this morning, and was rather surprised to
> find it ACTUALLY WORKS AS ADVERTISED! You coulda knocked me
> over with a feather!
EvapoRust does work (and for someone else who asked, this is the stuff Moss
Motors sells on their website if that helps you find it). However, it is
expensive and the effectiveness of the solution seems quite short - at least
with my expectations on how much it costs per gallon.
Randall later wrote:
> I suspect good ol' phosphoric acid works just as well or better.
It does. This is what my machine shop uses to clean heavily rusted blocks
before putting it in their other cleaning aparatus (jet spray, oven, airless
shot blast is the usual procedure). What do they use? I asked once and
they told they mix it up themselves, using regular Molasses. The key was to
let the solution sit for some period of time before using it, to allow it to
ferment. It seems fermenting Molasses produces phosphoric acid. The mix
ratio they used was something like 7:1 water to molasses.
I suspect that any acid solution will bring worries of hydrogen
embrittlement of the base metal. Although this could be the reason that
they then bake the blocks after being rinsed in the jet spray cabinet.
What else? They kept the plastic drum outside because the mix STUNK! Which
is one of the things that has kept me from mixing up my own molasses rust
remover.
Kai
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