Cleaning Rust Stains On Aluminum

[HAP]

Anyone have any suggestions on how to clean rust stains off of aluminum? Its an open top aluminum water tank used when filling SCUBA tanks with air. Previous owner had some steel angle iron in the bottom to keep the tanks upright. Would like to clean it up as best possible.

Thanks,
HAP

[RWO]

Oxalic acid wood bleach is a great rust remover and should not attack the aluminum excessively. It can be found in woodworker supply stores. Phosphoric acid will also work. It is sold for treating auto body sheet metal before applying primer.

Easiest mechanical method would be sandblasting. Then there is always the sidegrinder-sanding disk method.

RWO

[Evan]

Battery acid will work and it doesn't attack the aluminum. Use protective eye wear and worthless clothes. Add acid to water only, never water to acid or it can boil and spatter acid.

[H380]

http://www.envirotechcoating.com/Aluma-Brite/

It etches the aluminum. We use it on bare aluminum boats before we paint or put super slick on the bottoms.

[lazlo]

When Doc posted about the aluminum cleaner he found with dilute hydroflouric acid, I hunted around and found "Mag Wheel Cleaner" at NAPA autoparts which has the same mixture.

You spray it on, immediately start rubbing, and then wipe it back off. You end up with shiny aluminum without a ton of rubbing/buffing - stuff's magic!
I've found it's also great for prepping aluminum before welding -- it eats away the oxide layer, so you don't have to buff or wire-brush it off...

Edit: H380 and I cross-posted. Aluma-Brite is the same stuff (hydrofluoric acid). I think it's what Doc used.

[HAP]

Thanks for the replies. I'll pick up some mag wheel cleaner for the job.

HAP

[aboard_epsilon]

just polish it off with fine grades of wet and dry

all the best.markj