What kind of finish is on the aluminum bumpers?

[vangremlin]

I just had my bumpers sand blasted and then powder coated.  They were pretty cheap to have sand blasted, and not all that expensive to have powder coated.  They turned out really nice.

[Budwisr]

Just thought of this......a bumper only weighs 8lbs. So definitely an alloy metal.

Yep, its an alloy, stainless steel. If you grind on one, it'll throw sparks. Aluminum does not throw sparks.

[priya]

Yep, its an alloy, stainless steel. If you grind on one, it'll throw sparks. Aluminum does not throw sparks.

I'll try that tomorrow.   I know it weighs the same as a much smaller piece of steel.

[rollguy]

Just thought of this......a bumper only weighs 8lbs. So definitely an alloy metal.

Yep, its an alloy, stainless steel. If you grind on one, it'll throw sparks. Aluminum does not throw sparks.

I vote for aluminum. Try a magnet.  The bumpers are not magnetic.

[mudkicker715]

[/quote]
I vote for aluminum. Try a magnet.  The bumpers are not magnetic.
[/quote]

Stainless is not magnetic. Good stainless anyway.

[vangremlin]

When I took my bumpers in to be powder coated, he told me they were aluminum.

And I agree, stainless steel is not magnetic either.  I got a new refridgerator over the summer that is stainless, none of the fridge magnets will stick to it.  No more refridgerator art!

[rollguy]

304 stainless IS magnetic (and will rust), but 316 stainless is NOT magnetic.  The Eagle ALUMINUM bumpers would oxidize (as stated earlier) if they did not have some kind of finish on them (anodize, clear coat, powder coat etc.).

[priya]

if they were stainless bumpers, no anodizing. they are clear anodized. aluminum starts corroding the moment it gets oxegen to it. it turns dark gray REAL fast. i think its ZOOPS that has a nice aluminum sealer that you polish the aluminum with, and it seals and keeps it shiny. now that you got that anodize off, you got to strip the entire bumper, and put something else on it. if you take some "never dull" and just keep rubbing in one spot, it will just keep being dark gray on the neverdull pad. thats the constant oxidation. stainless steel will NOT oxidize. you can just polish it up, and its like chrome. no coating needed. even if its an aluminum alloy, it will still oxidoze in no time, and be dull. since you already got started on removing the anodized coating, finish it up, and look into the zoops aluminum polish. its the only thing i really know of that will polish/seal aluminum and keep it shiny. good luck.

o and the car looks OUT STANDING!!!!

Thanks for the advice and compliment Casper.  I'll have a look for the Zoops.

[BenM]

I've seen some that are aluminum and others that are chromed steel. I don't think the aluminum ones I have are anodized, though. They look solid throughout.

Someone here TIG welded up the bolt holes on his, and it was definitely aluminum.

I would imagine it varied by year and trim.

[priya]

Yep, its an alloy, stainless steel. If you grind on one, it'll throw sparks. Aluminum does not throw sparks.

Well, I took the grinder to the bumper and no sparks.  I've seen a lot of stainless steel in my time and quite a bit of raw aluminum and it sure looks like aluminum to me.  That combined with the much lighter weight than steel and I'm certain the bumper is aluminum.

I've seen some that are aluminum and others that are chromed steel. I don't think the aluminum ones I have are anodized, though. They look solid throughout.

If you look at the picture I posted you can see mine has a coating. I thought mine were solid throughout too before I started sanding.  Paint solvent and paint stripper wouldn't touch it, I'm using 40 grit to get it off, its very tough so I'm certain that it is a clear anodizing.

[Budwisr]

Well, I took the grinder to the bumper and no sparks.  I've seen a lot of stainless steel in my time and quite a bit of raw aluminum and it sure looks like aluminum to me.  That combined with the much lighter weight than steel and I'm certain the bumper is aluminum.

Well I stand corrected. I originally thought that they were aluminum until a couple years ago when I took a couple mangled bumpers to a recycle place. I had a bunch of copper and I thought I would get a couple bucks for them so I took them along. At the yard they used some sort of acid test on them and claimed they were not aluminum but stainless. When I heard that, I fiqured they weren't worth much. Actually they paid more for them because they were "stainless". I assumed they knew what they were talking about. About a year ago, I buffed out the bumpers on my Father's Concord and they did not seem like they were anodized, yet they were somewhat shiny, so it made sense that they were not aluminum. I'm guessing they might be chrome? This weekend I'll check the bumpers on the Eagles I own. I have five ranging in the years from 81 to 87 so It should be a good indication. Sorry for the misinformation. BTW Easy-Off oven cleaner is supposed to remove the anodizing from aluminum.

[priya]

BTW Easy-Off oven cleaner is supposed to remove the anodizing from aluminum.

Cool,  thanks for the suggestion, I'll give it a whirl.  I was thinking I wasn't going to do the front bumper because its way too much work but if the Easy Off works better I might do the front as well.

[milliard431]

I happened to wipe off my bumper with a cloth that had goof on it that I had used to wipe up after removal. OMG did it shine up nice. On my front gumoer I just have 2 spots on each side of center whee a license plate had rubbed and scratched through the clear coat. Also have a couple spots of "white rust" but I may just give it an honest cleaning. It has just 58,000 on it now so I am trying to do a sympathetic restoration. I gave up on the cheap paint job idea though as there were quite a few of those parking dings on both sides so the restoration shop tally is up to $2000. In the end it will be a collector grade Eagle with an honest restoration. I still would not ask $10,500 like that other guy. My old paint's shine was as nice as any I've seen but no comparison to a modern 2 stage. Yes I did say 2 stage. I had said I wanted to go with 1 stage like it originally had but was convinced otherwise. I was told that it would come across as a short cut and also would not last as long. He also was happy to grab another $400 from my pocket but others have given me the same advice so I think he was just being honest. Originally he asked me the usual question, How long are you keeping it? I just said that it really doesn't matter as money was not my motive. I kind of feel like i have a responsibility here as how many low milage 1980 2 door sedans do we really have. I mean this baby never had even 1 rust bubble on it which is why I thought they would just about paint it for free. NOT! I have learned that a proper paint job will set you back a bit. It is far better to get a small loan and buy the best condition car you can. I know you've all heard that before but if you really like your cars done right it is cheaper. In this case I still got the best 1980 2 door that I have seen and now it will be a 1 footer instead of a 20 footer. Those small issues never show up on camera.

[BenM]

I've seen some that are aluminum and others that are chromed steel. I don't think the aluminum ones I have are anodized, though. They look solid throughout.

If you look at the picture I posted you can see mine has a coating. I thought mine were solid throughout too before I started sanding.  Paint solvent and paint stripper wouldn't touch it, I'm using 40 grit to get it off, its very tough so I'm certain that it is a clear anodizing.

If I remember around Christmas I'll go check a rough looking one I have in storage. All the ones I have are really hazy on the front and the bolt holes are corroded. That's why I'm not sure if they are coated in any way, or they could have just been buffed one too many times.

[BenM]

Not only will bolts rub away a coating, but aluminum is sacrificial around iron. I reinforced mine with steel plates and used a gasket to isolate them.

But I still see a haze reminiscent of untreated aluminum, so I hesitate to be sure that they all got the coating. I don't want to damage the ones on my car.

It's still a very good metal for exposure without anodizing because the surface corrosion protects the metal much like copper.