Renewing Chrome Trim - DIY with Classictrimcoat

[ncsubowen]

Incorrect. The euro bumpers are chrome plated steel bumpers. You do NOT want to sand on them.

Oh man, my fault. Listen to this guy.

[netcsk]

European bumper will apply to these also ?

Yep - anodized aluminum all around.

Incorrect. The euro bumpers are chrome plated steel bumpers. You do NOT want to sand on them.

[ncsubowen]

European bumper will apply to these also ?

*Edit - Incorrect on my part. This does not apply to euro bumpers, as they are chromed steel.

[Old city bimmer]

European bumper will apply to these also ?

[tonerrrr]

How did you get just the chrome part off the kidneys? Isn't there a plastic rivet in there?

Also, your bumpers look amazing. Great work.

I think there is one on top and two on the bottom or something like that. Push the rivets through with these small tools: http://www.harborfreight.com/4-piece...set-66836.html

Thanks a lot!

[ncsubowen]

Here are a few pics from when I did some. Also, a little "headlight restore" pad with a drill works wonders for kidneys and other parts. Just use a little polish!

The bumpers are a friggin bitch. I only recommend doing them if you are prepared for a lot of work.

In my pics you can see the anodized part of the bumper coming off when sanding. Hopefully this clears up (omg pun) the confusion for some. There is no scrubbing that will get this off, only sanding IMO.

How did you get just the chrome part off the kidneys? Isn't there a plastic rivet in there?

Also, your bumpers look amazing. Great work.

[SkiFree]

As mentioned you can't really REALLY polish anodized aluminum trim. There are a couple ways to tackle it, just depends on how much time/money you want to sink into it.


1) For light haze: just use a "polish" as mentioned above.


2) For scratches that not removable with "polish" you will need to remove the old anodizing (use anything with Lye in it [sodium hydroxide], I found a $10 bottle of "Hair and Grease remover" from Home Depot to work like a charm).

Once the anodizing is removed you can either

A) polish the bare aluminum and throw some spray-on clear coat on top.

https://www.youtube.com/watch?feature=player_embedded&v=3Jdlo-AQoAY

B) Have the parts re-anodized. If you choose to Re-anodizing the trim there are some basics you should be aware of a couple things ....

When anodizing an aluminum part the final finish depends largely on the surface finish of the part you are anodizing. Simply put, the more polished the part is when in goes into the anodizing tank, the shinier it will be when it comes out.

Now when you take trim parts to an anodizer the first thing they do is strip the old anodizing (if the part isn't anodized to start with it still goes in to clean the part). The stripper used is fairly abrasive and the part comes out with a flat/matt surface finish. Typically part is then put into the anodizing tank and given the matt-finish at that point, that's what you end up with for the final finish.

To avoid a matt-finish when re-anodizing you should plan on intervening between the anodizer's cleaning bath and the anodizing bath by picking up the parts and polishing them.

Hope that helps...

Clearly you don't get it then and are becoming obstinate. How am I "right" when I've said there's more than one way to go about it?

To reiterate.

1) remove anodizing completely (using a sodium-hydroxide based solvent, aka lye, aka draino, etc. NOT some generic "de-oxidizer").

2a) then polish, clear, and call it good.
OR
2b) then polish, anodize, and call it good.

[tonerrrr]

Here are a few pics from when I did some. Also, a little "headlight restore" pad with a drill works wonders for kidneys and other parts. Just use a little polish!

The bumpers are a friggin bitch. I only recommend doing them if you are prepared for a lot of work.

In my pics you can see the anodized part of the bumper coming off when sanding. Hopefully this clears up (omg pun) the confusion for some. There is no scrubbing that will get this off, only sanding IMO.

[ForcedFirebird]

Mine? They were OE on that car, painted - they were black plastic when I originally bought the car. The whole car was painted 4 base 3 clear coats, color sanded and polished.

[ncsubowen]

Did you grab your bumper surrounds off a vert or get yours painted?

[ForcedFirebird]

As mentioned, aluminum polish doesn't work so well because of the clear anodize, I find clay bar and/or a buffer works the best to make it shine again.

Polishing the bumpers is a pain in the butt. It took hours to do my front and I still need to get a good rear and do that one. Here is what I did.

We used a flat disc grinder with 80 grit to get the chrome off of the bumper, then stepped up to 120 then up to 160. We then switched to a DA sander and went all the way up to 1000 with that. Then we wet sanded it by hand up to 2000 switching directions from one grit to the other to make sure we went far enough down. Then we used a high speed buffer and some extra cut compound to get it close to the finish. Then finally put a latex glove on and hand polished it with Mothers Billet Metal Polish about 3 times over the whole thing and used a microfiber towel to take that off. Then covered it in tape before putting the bumper back onto the car.


And you can see how clear and good the reflection is here.

I have since redone it again and have put a sealant on it to protect it even more.

For mine, I used a 7" variable speed polisher/sander with a 220 grit sanding pad. Took about 20min per bumper to strip them of the anodizing. Then 320 in a DA and then just brought them to a polishing place to finish up.

Pain to keep clean, but occasional rub with Mother's aluminum polish and a good coat of wax made them stay decent.

My results...

[ncsubowen]

Shit that is amazing. I wonder if it wouldn't be easier to get a shop to chrome them?

[McGyver]

I've always hated how much time it takes to do something perfectly, but that is a beautiful bumper!

[McGyver]

I could be wrong, but the AL bumpers have a coating on them, that will prevent any polish from work directly on the metal - and the metal can be tarnished UNDER the coating - Don't quote me on that.

I believe you are correct about this. The rear bumper on my vert was all scratched up, so I used a polish wheel on a drill with mother's mag and aluminum polish. It worked great once I worked through the layer of gunk that covered the bumpers, but it took forever and was really frustrating.

In the future i may try aircraft stripper followed by fine sand paper and lots of buffing.

[tonerrrr]

A quick trick to get your trim and bumper looking better is to just use back to black. It just basically fills in the imperfections and makes your trim look a lot better. Very temporary though as it's just a silicone or similar film. Good for cleaning your car up for a meet or photoshoot imo.