I recently bought a used vehicle which has some aftermarket rims on it. For whatever reason the previous owner failed to take good care of them and there are areas of them (some are 2 or 3 inches) that look like the chrome plating or finish has been chipped or corroded off. Is there any DIY product or method I could use to repair the chrome finish?
That's not steel and chrome, that's aluminum.
There is a coating over the rim. It's some sort of epoxy. It seals the oxygen from touching the aluminium so aluminium oxides aren't created. What you see there is aluminium oxide on the rim. I will slowly eat the rim and 2000 years from now it will be a small piece of aluminium.
To stop the creep of oxides you are experiencing you have to burn many calories.
First, get a buffing wheel and any kind of gritty polish. Chrome, rubbing compound, even wax, if that's all you have. Squirt a bunch of it every where and use the buffing wheel and start focusing on the worst areas. You will see it get nicer and nicer. You can also use 1000 grit sand paper to make it better. If you are getting pitting then it will take considerably longer. You will know what pitting is when you get there. Small intrusions into the aluminium that looks as if a small stone were there, spinning. You can be glad if you have no pitting.
This is a lot of work if you want to fix it
If you do fix it, be prepared to feel really good and have a sense of accomplishment because you worked so hard.
Buffing is an art. It's not next level but it requires patience. Sometimes you might want to squirt just a bit of water on the spot you are buffing. Get the cotton cloth type of wheel to put on a drill or other similar device that is handy.
Cloth with a bit of moisture and rubbing compound, 600 grit or higher, will begin to get a hard flat surface on it. That's exactly what you want. When you get it there, just keep adding little swipes of rubbing compound, chrome polish...to it as you go along.
It will make your rims shine, especially if you penetrate the clear coat layer that protects the aluminum from the elements (oxygen)
You can make them shine like chrome. It just takes awhile and A LOT OF CALORIES. If you don't have a drill at a minimum you will kill yourself doing it by hand, so don't do that.
They will look as good as you make them look. As time goes by you will want to buff them for maybe 30 minutes every month. If you like shiny, they will be good. If you don't like shiny, takes these down to a local aluminium recycling plant and get some beer money.
I did a set of these over Christmas that were much worse for it. I got hit by a car and polished rims.
They could end up looking like this if you dig deep and do it all weekend.
I would give it a shot, but that's me. Be prepared to do it for half the weekend, this includes sleeping in on day two because you drank 5 beers and polished on day one.
If you can get to done, you will be happy. Just go for it.
We see this hard chrome chipping and often. It is caused by the materials; specifically the large hardness difference between the chrome plating and the aluminum wheel material. The more flexible wheel changes shape as it is stressed by road bumps and the hard chrome cannot flex so it breaks away. Then corrosion gets going under the cracked away flakes.
After attempts to salvage several sets of wheels with this disease with no success... I would replace the wheels.