Cleaning up pitted rims:
Well on my second to last day of vacation I got enough of the "Honey do" list done to to do some detailing on the Vette. I thought that the aparent tar build up on the inside of my wheels should be taken off. To my horror I find it's aluminum corrosion, like rust pitting, but they look like black spots like tar.
Short of machining my wheels is there anyhting I can do on my own to improve matters?
Thanks,
Bluemill
I purchased a 2004 Corvette with polished aluminum rims with the factory clearcoat. The barrels of the rims were a complete mess, pitted, corroded and filthy. There is hope. First, I removed the clearcoat from the rims because I didn't like the "milky" appearance of them, anyway. I used Klean-Strip Aircraft Peeler Clearcoat & Basecoat Remover - EFS459 purchased at Autozone. You can buy an aerosol can or a 1 quart can and apply it with a paintbrush. I would recommend buying the quart and brushing it on. It will save you money. WEAR GLOVES!! The grits on the sandpaper were so smooth, I didn't realize I was slowly sanding the skin off my fingers until they were
bleeding. Light cotton gloves worked fine. First, clean all the loose crap off the rim barrel(s). Then apply a coat of the clearcoat remover. This will remove any of the remaining clearcoat so you can get to the bare aluminum. REMEMBER: Once you remove the clearcoat, you will have to polish and wax the rims and barrels to keep them nice. This is a no-brainer to me. For a fairly small investment of time, your rims will look much better than even brand new stock clearcoated rims. Once the clearcoat sets for about 15 minutes, hose it off. Here are the steps I used to turn my disgusting, pitted, filthy barrels back to a mirror-like finish: I bought a wire drill brush and put it on my drill. I bought a 4-inch drill brush at home Home Depot for about $5. I used the wire brush to grind away all the grim.
[UPDATE: Be sure to use a wire brush that is not too aggressive (fine bristles). If it's too aggressive, the wire brush marks will be MUCH harder to wet sand out. It still can be done, just LOTS and LOTS more elbow grease. Again, the best method is to start out less aggressively and work your way up until you see the corrosion disappearing. All rims will vary depending on the amount of neglect, so you may be able to jump in at a finer grit and save time.] Take a piece of tape and wrap it around one of the spokes of the mag so you don't do the same area twice. Trust me, if you don't do this, you'll lose your place. Do a small area (approximately 2 inches X 2 inches) at a time, being sure to rinse the area frequently and keep it damp. This is a grueling process that took me over an hour of grinding on each rim. If you think you can get away with it, try using a lesser grit of sandpaper to start and work your way down to the more aggressive grits until you see the corrosion disappear. If your rims are like mine, you'll need the wire drill brush. BEAR IN MIND: If your rims are pitted, you will not be able to remove the pits. Do not despair, though, since they will become hardly noticeable unless you are examining them closely, and the mirror finish will make you smile. Once you finish cleaning all the corrision and black crap from the barrel, rinse well and then use 320 grit wet sandpaper. All these sandpaper grits can be bought at Autozone or probably any good auto store. If there is an area of your rim barrels that looks perfect, then leave them alone and only work on the corroded sections. I ended up doing every inch of my barrels. Wet the rim and take the 320 grit paper (by hand) and sand right-to-left about 100 times (yes, I counted), starting from the inside and working towards the back of the rim. After sanding the first sectioin, move out a little towards the back of the rim and said back-and-forth another 100 times. Repeat this until you have removed all the corrosion in that section of the barrel. If you are insane like me, you can do the outer lip. Then turn the wheel to the next section and repeat. Remember to keep rinsing every 10-15 seconds. You will see the water turning grey or black as you sand and remove the aluminum material. Once you have completed a circle around the entire rim, you are ready for the next grit. Each grit will take approximately 45 to do. This is a VERY labor-intensive job but if you set aside the time and just go for it, you will be happy you did. After the 320 grit, move up to 600 grit and repeat the process all the way around the barrel, rinsing frequently as you go. If you notice that you missed a spot, go back to the more aggressive grit and start over on that small area and work your way back to the grit you are currently working on. After 600 grit, move up to 1500 grit, then 2000 grit, then 3000 grit and finally 5000 grit. I've read that some guys stopped at 1500 grit and polished, but they they mention that you will see scratch marks. If you use all the grits I've mentioned, there will be NOTHING but a mirror-like finish with ZERO sanding marks. Yes, the pitting will remain, but the difference is striking. By the way, the 3000 and 5000 grits are actually a foam-like pad. All the sandpapers I used were made by 3M. Once you reach 2000, you can lessen the elbow grease and just let the paper do the work. Keep an eye out for any imperfections or scratches you've missed, and you can easily go back to the 320, 600, 1500, 2000, 3000 and 5000 to clean them up. Once you are ALL DONE sanding, grab some heavy-duty rubbing compound (any brand) and also a light-duty rubbing compound (any brand). First, apply the heavy duty compound just like you are waxing your car, and once you are done with the heavy duty, move up to the lighter duty compound and do the same. NOW you are ready for the polish. I used Mothers Mag and Aluminum Polish and Wheel polish. You don't need the Billet polish since our wheels are NOT billet and the billet polish is VERY expensive. Once you polish, use some type of year-round wax to finish the rim. There are many products you can use after the polish, and it's personal preference at this point. Now your barrels will look 99% better. The entire job took me approximately 6-7 hours per rim. As far as the small marks on the FRONT of your rims that are near where the spoke attaches to the outer rim, this is simply corrosion also. Again, spray the clearcoat remover all over the front of your rims. If you get any on the tires, simply clean it off. REMEMBER: Once you remove the clearcoat, you will need to polish and wax the rims a couple times a year, but the shine is amazing. When I rinsed off the clearcoat, my rims were like mirrors. Once you have the clearcoat removed from the front, you can take 1500 grit paper and work it into the corners where you probably have little black corrosion that look like small black dots. I was nervous when I did this, but with the 2000, 3000 and 5000 to follow, the mirror finish comes right back after you remove the black dots. I could not tell the sanded area from the factory polished aluminum. It may take about 15-30 minutes for each small area, but you WILL be able to remove the blemishes and make the rim look pristine. REMEMBER to keep rinsing as you sand. Then apply the two rubbing compounds as described earlier and follow up with the aluminum polish. I'm sure if you want, you can get them re-clearcoated somewhere, but after seeing how amazing my rims look, I would never. Hope this helps. I've attached photos. I just joined the forum today, so I hope I did it right. One last update: You will notice in the photo of the front that the center cap is still dull and clearcoated. I have since sprayed the clearcoat remover on it, and it now matches the shine of the rims with logo still intact and looking perfect.
Some Forum members are inquiring about the black oxidation marks that show up on the front parts of the rims. Once the clearcoat breaks down, oxidation will soon follow. The most common oxidation appears as small (or large) black specks or dots, especially in the corners of the mag struts. These cannot be polished away - they must be sanded out. If you follow the same steps outlined above and remove the clearcoat from your rims (as I did) you will be able to remove the black pitting and completely restore a showroom mirror shine. I have attached photos of a nasty corrosion mark that I had on my wheel (about quarter size). Again, AFTER the clearcoat is removed, I used 100 grit sandpaper since this was really nasty area of corrosion. For the smaller specks, you can begin with 180 or 280 and move up through the grits from there - again, following the above steps. If you look closely, you can see hairline scratches on the rim. These were caused by scrubbing the rims with a nylon brush (my bad). These lines were also completely removed once I finished the sanding and polishing. Obviously I use a soft sponge to wash the rims now! Good luck.
4LT GS Roadster
