I've been wet sanding set of arms with 400 grit paper. I almost have all the dings and all the anodizing off. What grit should I go with for the nice brushed aluminum look? Will they oxidize if not protected? Should I consider clear anodizing or clearcoat paint?

Here is a post I wrote on BMXMuseum.com.......

If you want the original finish restored, you don't want them polished. As you probably know, they had a satin finish, almost a clear satin anodize look.

When I restored mine, I started trying various methods I read online on 1 crank only, using the other one as reference for original finish. Mine were pretty nicked up on the logo side, deep nicks and scratches, but the back sides had a good reference for what the whole crank used to look like. Anyways, I started with 200 grit, getting out the deep stuff. Then went to 400 wet sanding, 600 wet, and 1200 wet. At this point, the arm should look almost polished. I tested 3 different scothbrite pad colors (green, then dark gray, and finally white, any paint store carries all the colors). Most online suggestions say the green is the way to go, but its WAY too aggressive. The dark gray gave a real nice dull satin surface, but almost too flat and a little too grainy. The white pad however gave the best surface finish. All of the above processes I used parallel strokes, With the white pad, I used a swirling motion due to the fact its finish was so fine, finer then even 1200 grit paper. It give the perfect finish. I tried going parallel with the white pad, but it started polishing the surface. So I switched to a swirl and it worked (very very light pressure on the swirl motion, don't grind it in). Very very close to original and I am very picky. It took me 2 months testing different methods.......

I never clearcoated my arms and they are fine. I slapped some AJK repop stickers on and they look OG.

Jeff