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autobon7

How to clean up hazy/light to medium scratches on 75 bumper?

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I searched and found a couple ideas. I'm not looking for show quality just a bit more shine and clarity. My camera is inop so I cannot provide pics until this weekend. But can tell you that most unloved 02 bumpers that I have seen all look like mine. Both bumps are straight and no dents just dingy and surface scratchy. All thoughts/ideas are welcome.

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I have a lot of experience polishing aluminum and other metals (was obsessed with it for years). It really depends on how deep the scratches are.

In short, the process for restoring aluminum back to a shine is as follows (assuming you don't have specialty tools available to you which make this all go by far more quickly).

Remove the existing finish (clear coat, usually) using a paint stripper or by sanding with around 250 grit paper, always in ONE DIRECTION PER GRIT SIZE.

once the finish is off and you are down to bare metal, sand with the finest grit that will quickly remove the scratches. you don't want to puddle the metal to remove a scratch as it will have a wavy finish once you polish, so you want to remove an equal amount as possible from the entire surface to be finished. Once the scratches are no longer visible, grab some 350 grit sand paper (assuming you start with around 250 to remove scratches) and go in the opposite direction using water with a dash of soap as a lubricant. you must have a uniform finish across the entire surface, otherwise the 250 grit scratches will show up in the end. so, 350 in the opposite direction until it all looks the same.

Then from here on the process is the same; Reverse direction with each finer grit until the previous scratches are completely removed. Go 350, 500, 700, 1000. It may seem you are wasting time, but believe me, doing it right now will produce what you want in the end. By the time you get to 1000 you will have a nice dull shine going. You can either leave it here if thats the finish you want, or start with buffing compounds and wheels. This is a whole new section and an artform of its own (takes about 20 hours behind a wheel to just start getting a consistant finish, around 100 hours to get something you are really proud of). My process at this point is to go to a sisal wheel with emory compound, then tripoli (brown) with a sown cotton wheel, and on the finest of parts I'll go as fine as un-sown cotton wheel with white compound, but thats a bit fine for a bumper.

ask me whatever you want...

_DSC0008.jpg

Yes, that is a completely polished crankcase. Tricky piece; tons of crevices and cannot heat the part at all otherwise cases won't seal evenly. Took a few hundred hours to polish everything on that motor.

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That looks amazing Rocan. I can just imagine the dedication involved with that project. I don't think I want to put in that many hours on my bumpers though. Plus I don't have any of the power tools you mentioned....it'll all be elbow grease.

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because the big bumpers, like the belt line moulding is anodized, polishing to the bright finish as shown in the above pic can not be achieved unless you strip the anodizing....which isn't an easy task

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So what product can I use that would make it look better? Not looking for show quality....just a bit better will do (for now).

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You can clear coat it.

Its anno'd, so forget about polishing it unless you strip it first.

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because the big bumpers, like the belt line moulding is anodized, polishing to the bright finish as shown in the above pic can not be achieved unless you strip the anodizing....which isn't an easy task

Oven cleaner works great for removing anodizing...

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Oven cleaner works great for removing anodizing...

sadly, even the strongest oven cleaners i've ever been able to buy did not scratch the surface of the anodizing...

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