Removing Oxidation and Staining on Aluminum Rims
 

Hello all, and thanks in advance for your advice.

I have a set of Nisi Toro 27" clincher rims mounted to early 80s Shimano low flange hubs. I want to use them on a rebuild project, but the rims have spotty white oxidation with some brownish/greenish tinted splotches. The rims are not anodized and were once a polished finish, I think. I'm sorry that I don't have any photos to attach.

So, what I've tried so far:
- ammonia and a toothbrush - maybe a slight reduction in the spots, certainly cleans off dirt.
- Marvel Miracle Oil - saw this application on YouTube for motorcycle aluminum - it removes oxidation pretty somewhat.
- EasyOff spray - tried a small portion, and left it on for about 15 minutes, then toothbrush - it didn't remove very much.
- MMO with a green scouring pad - removes more, but leaves faint scratching, which I'm guessing that I can buff out with Mothers

Is there some other chemical process that can dissolve the white oxidation? I don't mind polishing them afterward. Thanks. Phil G.

I'd go with an abrasion/polishing process rather than chemical. You can start with an appropriate grit Scotchbrite pad, then work your way to finer grits, then finish with polishing compounds on a rag, working from white diamond to tripoli or rouge, depending on the finish your looking for.

Note, however that these rims were never polished when new. New Nisi rims had what is is often called a mill finish, or the satin gray color of evenly oxidized aluminum that you might see on industrial or raw aluminum products. They used to weather to a duller gray, but like other bare aluminum items were subject to those white dots if left in a damp place for a long time.

There are aluminum polishing compounds for exactly this problem. They are often used for cleaning up alloy rims on vehicles and come in various formulations from light cleaners to heavy polishes to restore badly neglected rims. Go to any good auto parts supplier and you'll find several brands of them in the wheel care section. If all else fails, go to Eastwood Automotive online, they sell restoration and finishing products including several for rehabbing aged aluminum. Most products like these have a wax or other protectant base, so make sure that you wipe your braking surfaces with some mineral spirits followed by a wipe with alcohol to get them good and clean. Alcohol alone won't remove waxes.

Be careful with home remedies like EasyOff and ammonia, some can cause a haze on the surface that can't be easily removed. Never use acidic products like lemon juice, CLR or LimeAway on aluminum alloys. They work for removing pinhole rust blooms on chrome but can damage aluminum surfaces.

EasyOff (caustic soda) and Ammonia will dissolve aluminum so be very careful in their use. I'd also be very leery of using a wax or oil based cleaner unless these rims are only for display, not actual use, as either will leave the brake track very slippery. Marvel Oil can be used on motorcycle rims because they have disc or drum brakes and don't rely on the rim for brake friction.

I polish aluminum or pitted/rusted chrome with..... aluminum foil. Wadded up in a small ball, it works great.

It is NOT good for close-up inspection, as it will make fine scratches. If I want to remove the fine scratches, I apply Mothers Aluminum polish afterwards. With Mothers, I like to use pieces of foam rubber (often found as packing material). I always hand onto a small pile of foam rubber, when I get some in.

They work as an excellent applicator, buffer. Disposable, and free.

DO NOT use Easyoff, it will ruin your rims.

I have had success bringing back Al rims with Mother Aluminum Polish. It's a manual process, you fingers will be sore after, and black. But it works pretty good.

elbow-grease ,, it was called .. hand labor .

Check your local industrial cleaning supplies place. They have all you need. Most stuff is very strong...up to you to decide :)

Thanks For All Of The Replies
 

I really appreciate the informative replies. So, I found out that the rims weren't polished originally (thanks, FB), but they will be now.

I realized that using the MMO would require me to thoroughly clean (with soap and, later, alcohol) the brake track. I'll also use very soft brake pads.

Looks like a lot of hand polishing and patient work. Thanks again, everyone. Phil

Mothers is semi aggressive stuff, but you might try something a tad more aggressive to start with if those spots are deep, which they can be on softer aluminum alloys. Like rubbing compound or even Brasso.

Total waste of time.

Time you enjoy wasting is not wasted time.

+10

I'm no expert. but IMO the aluminum in those days was the same as on house windows, and NOT the same as new stuff.

Concur.

the problem is especially pernicious if the stuff gets into small nooks and crannies... Like under spoke eyelets, into spoke holes and rim joints. Once it gets in there it is difficult to impossible to get it out, so the chemical reaction continues for a long time.

Thanks. I did a wipe down and ammonia/water light rinse with a cloth (over the area where I sprayed the Easy Off, which was about a 2" arc), but I will do a clear water rinse again, just to hopefully neutralize remainder.

I've really learned from all who posted replies.

The white spots are calcium.....CRL cleaner will remove calcium,rust and lime.....HMMM!....:) It will also leave a pit behind,where the calcium was.

if you want to polish the wheels.
stop by a harbor freight store and buy this, Aluminum Polishing Tool Kit - 14 Piece, polish kit for $20 and add elbow grease

no matter how well polished your rims
they will return to a dull silver after not too long
as aluminum oxidizes extremely fast when unprotected

although
the oxide layer is called aluminum oxide
and it is a actually a ceramic and is very stable
and protects the raw aluminum underneath
so i recommend removing the offensive blemishes once
then leaving the rims to age naturally

You could try some 0000 steel wool and WD-40. Spray the area you want to clean up, then rub with the steel wool. 0000 is a fine steel wool and won't leave scratches.

Rob

Just in case you ever wanted color-coordinated rims, these damaged ones would be a good choice for powder coating. I had mine done by Ed Steidle in Florida for $25 each including masking the brake track. Here is his email address:edward steidle <woodland847@yahoo.com>. Best price I was able to find and good service to boot.

Don't get me wrong; I know that isn't what you were asking. Just sayin' if you were ever thinking about doing this, it would be a good way to deal with these corroded rims. The grit blasting step that precedes the powder coating will probably clean up the imperfections, and the coating will go on smoothly.

+1 On using aluminium car rim polishes.

Meguiars Hot Rims Polish puts Mothers to shame.