cast aluminum wheels....pitting! how to get it out? will they come out?

[soccergk]

I am polishing a set of porsche wheels. Im still on 80 grit with the DA. will the pits come out or are they throughout the wheel? is this a lost cause? i hope not


wheels in question



my manifold i did, all done by hand...no buffing wheel

[jrow]

soccergk,

Will the pits come out! They may or they may not depending on how deep they are.
I think 80 grit sandpaper is a little severe. I would probably start with about 180 - 220 grit, then move to 400 - 600 grit and see how that would polish up. You may also want to try greaseless compound. Your will need a Dremel tool or some means to get into the slots on those wheels also.

John

[polierator]

I usually start at 60/80 to get off the paint and to get out the pits.
If im sanding by hand or by machine, i don't care about it. Then i move up to 120, 240 and so on...

The pits in some rims are very deep in the material. But they will come out like jrow said.

Are your rims originally from porsche?

[soccergk]

yes they are from porsche, the paint is stripped i spent about 1-2 hrs on one and another hour on the other and you can still see the small pits... they look like little black dots

[mpierich]

Originally Posted by soccergk

I am polishing a set of porsche wheels. Im still on 80 grit with the DA. will the pits come out or are they throughout the wheel? is this a lost cause? i hope not

You're making extra work for yourself with the 80 grit, but that's up to you.

As for the pits, it's a matter of how much material you're willing to remove before you realize and admit that they are throughout the casting. It happens. Keep track of a small area - if new ones appear as you sand away, you'll know.

Originally Posted by soccergk

my manifold i did, all done by hand...no buffing wheel

Very nice! But sounds painful...

[arrowheadracinginc]

I agree on the pits. Alot of older motorcycle parts I polish, just have a never ending apperance of pits. Its the **** porous cast material they use and the way they cast it. Sometimes you get lucky sometimes you dont. I would think that a porsche wheel would be pretty well cast though.....

[mpierich]

Here's an Offenhauser valve cover. It's even worse than a Norton side cover...

[soccergk]

mine werent nearly that bad, i just worked on one wheel today, got it up to 600 and it looks like it is going to turn out nicely

[soccergk]

just an update....got one wheel polished up to 3000, no more pitting marks i was also able to sand out a pretty deep scratch which i was happy about