DIY - Anodized trim refurbish

I refurbished the anodized trim around my front grilles by sanding the hard anodizing off and buffing it back out. This requires periodic polishing but is easy to do. This is a workaround to re-anodizing the trim like factory original.

The kidney is just aluminum so I used a flat head screwdriver and dollied all the dents down as smooth as I could before sanding. It's very thin so you can't sand too much, so there's a few tiny pits here and there that I didn't want to sand out. I think I started with 400g and ended at 1000g or 1500g, then polished with a 6" cloth wheel on a drill motor with Blue Magic metal polish. I think most any metal polish will work okay.

The headlight grille surrounds are anodized aluminum, I believe, and very very hard. They're thicker though so there's more to work with. I actually started dry sanding with 80g to cut through the hard outside layer then used 150g/240g to work the heavy scratches out before sanding down to 1000g, then used Blue Magic to finish. I started with 240g on the first grille and it was taking forever, found it easier to cut through the hard layer and then clean up afterwards. I did all the sanding by hand. The good thing about just polishing out aluminum is if you find areas that aren't done quite good enough you just start sanding again and fix it. I'm happy with the way they turned out.

In this photo the top grille hasn't been touched yet and has heavy pitting. The bottom grille has been sanded and polished and has a couple areas on the right that needed more sanding. I think I probably used 800g then 1000g to sand it out, then polished.

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dave v. in nc

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Good info....I assume that you removed the grille surround before sanding/polishing...? One of the more difficult things to me, anyway, is holding the pieces to sand/polish safely and comfortably. Same with any gangly pieces; windscreen trim, etc. With belt line trim there is more there to clamp, or even attach it to a piece of wood/etc...
 

dang

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Good info....I assume that you removed the grille surround before sanding/polishing...? One of the more difficult things to me, anyway, is holding the pieces to sand/polish safely and comfortably. Same with any gangly pieces; windscreen trim, etc. With belt line trim there is more there to clamp, or even attach it to a piece of wood/etc...
I was going to paint the grilles anyway so I sanded and polished with the trim on the plastic. Masking was fairly easy with the thick trim.
 

eriknetherlands

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Fyi, getting the old anodising layer off can be done with hard labor and 80 grit sand paper.

But you can also use your favorite oven cleaner, and sit back and enjoy the beauty lines of your coupe while the chemistry eats it away. Then continue with the grit needed for the worst pit or scratch.

Magic ingredient is Sodium Hydroxide: Also known as caustic soda or lye (NaOH).
Drain cleaners which are hydroxide based also, will do it as well.

More info:
 
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tferrer

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You will never get 80 grit sanding marks out of the trim. 220 is as heavy as I'd go and even then that's pretty tough. If you have deep gouges in your trim pieces you may have to live with some imperfections even after sanding. My 2 cents
 

eriknetherlands

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@tferrer ; you're right, on the thin polished bright trim (as per original posting) going to 80 grit is a gamble. .

I had the 80 grit in mind as I redid my center console and dash grab rail. These had some serious scratches, and I did start with 80 grit, but then again these are not polished to a mirror shine: they keep their brushed look: At about 400 grit the appearance was as factory for these parts, I finished with a pass of 2000 grit to take the sharp hooks off; otherwise your cleaning cloth with hook to it.
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stphers

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I just did a complete set of trim on a 71 2002 Once done, I polished them with a no acid polish ( MASS polish ) and thencoated them with Everbrite, it seals the polished surface and keeps it looking shiny for a long time

Thanks, Rick
 

dang

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Ahh, I thought you were talking about the polished belt line time. My bad. Looks good.
I think the belt line trim is a lot thinner than the grille surround metal, not sure since I haven't tried the belt line trim yet. I did repair (hammer/dolly) the kidney grille on my E3 but they're so thin I had to compromise with tiny dings because there wasn't enough thickness to sand and polish. Just polish. It used to be a "20ft" grille but now it's a "2ft" grille so I'm happy. :)
 
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