Classic & Vintage - Oxidation on aluminium parts - advice?

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Oldpeddaller
10-04-09, 02:29 PM
I've amassed a pile of removed aluminium alloy rims, hubs, cranks, stems, brake callipers, derailleurs etc. recently that came from abandoned bikes left in a coastal atmosphere (salt-laden air). Whilst the parts themselves seem sound, the surface oxidation is very unsightly.

Before I consign these to the rubbish skip, is there a way to salvage them? I was wondering if something like household ammonia would be effective in dissolving the white "aluminium rust" from the surface wiyhout detroying the parts themselves? Any ideas?

If there is such a substance, how should I apply it (paint it on, submerse the parts in it?) How long would I leave it on and what would I need to neutralise it? Any other ways to restore things in this condition or are they likely to be beyond repair? None of the corrosion goes beyond the surface as far as I can see.

Or, brass wire brush, wet & dry paper & polish? ( a shine doesn't matter, I could spray them satin black before re-use). I'd rather recycle than add to land-fill if it's at all possible.

Your wisdom would be received with genuine interest. Thanks.


Ronsonic
10-04-09, 02:39 PM
If it is an unanodized part that has corroded just polish it by hand or machine with something like Brasso or Mothers. If it is anodized and that is failing you'll want to remove the rest of the anodize otherwise the result will be spotty. Oven cleaner works wonders for that. Spray on wait, scrub off. If the part is in real bad shape start the polishing process with fine sandpaper, say 600 or so and work finer from there.

There will be elbow grease. I'm not aware of any solution to the problem that doesn't require physically polishing the thing.

Oldpeddaller
10-04-09, 02:43 PM
If it is an unanodized part that has corroded just polish it by hand or machine with something like Brasso or Mothers. If it is anodized and that is failing you'll want to remove the rest of the anodize otherwise the result will be spotty. Oven cleaner works wonders for that. Spray on wait, scrub off. If the part is in real bad shape start the polishing process with fine sandpaper, say 600 or so and work finer from there.

There will be elbow grease. I'm not aware of any solution to the problem that doesn't require physically polishing the thing.

Thanks Ronsonic - at least this will keep me out of trouble for a while!


michael k
10-04-09, 04:26 PM
I use this to remove oxidation and clean Aluminum. :thumb:

http://www.duragloss.com/products/DG_0851.jpg

takingcontrol
10-04-09, 04:48 PM
A bench mount buffing wheel and a heavy set of welding gloves.

Sci-Fi
10-04-09, 05:22 PM
Depends on how bad the oxidation is. Polishing works most of the time on light oxidation. Baking soda, barkeepers friend, toothpaste with baking soda, etc make good low cost polishing compounds. Shower cleaners work. Vinegar is slightly acidic can can be used to remove oxidation before polishing...soaking times vary. Anything heavier and you will be in Phosphoric acid territory...might think about junking the parts at this point, it'll take some extreme buffing to get it looking good and may have to use fine sandpaper to wet sanding then buffing or use different grades of polishing compound...very labor intensive.

Oldpeddaller
10-05-09, 11:28 AM
Thanks guys, dome gppd ideas to try out. If I do find a "lazy" method, I'll be sure to post it!

Bheleu
10-05-09, 02:18 PM
Would the Oxyllic Acid approach work for Aluminum as well? I use Eagle Tech Neverdull, and I think that has some portion of OA? It requires scrubbing though.

mkeller234
10-05-09, 05:05 PM
Would the Oxyllic Acid approach work for Aluminum as well? I use Eagle Tech Neverdull, and I think that has some portion of OA? It requires scrubbing though.

I would say a big NO! I have tested this, I dropped some of the aluminum brake mounts, the crescent shapes, into OA and vinegar. They both disolved, the top layers of metal washed away... the OA worked faster than the vinegar.