Firstfives.org

I expect the process of removing the cloudy old anodizing is in the archives somewhere, but I just did it if anyone wants the details of the experience.

Bumpers are NLA from the factory. Step 2. Sanity would dictate taking the bumper to a local refinisher, pay the money and have a new anodized finish. Step 3. Do it myself, for no particular reason I can think of except wanting it shiney, scratch free again.

One big deal : Removing the bumper requires removing the (U.S.) rubber side pieces. 35 years, any rust at all on the bolts molded into the pieces, be prepared to stop, leave the cloudy bumper alone, or find, buy new pieces.

I used a Dremel tool wire brush to clean the exposed threads, penetrating oil over three days, only to have one or three of the bolts twist off. All it takes is one on the side piece to make it junk.

The bumper is now gleaming polished aluminum, no clear coat. Whether or not I've created a monster for maintenance I have no idea.

I polished the bumpers on my '76 buy selling it and getting a '74 with steel bumpers. I like doing things the hard way.

After working an an anodizing ship in Detroit years ago, you could 't have the anodizing re-done. Acid strip, polishing is usually warranted, not buffing. Polishing is what gives it the fine scotchbrite finish. Don't expect it to ever look new due to micropitting. There's clear coat and standard anodizing. Clear coat gets a final soak in a nitric acid bath. For polishing, I'd have them stripped first at an anodizer and if they offer polishing have them do it o a wheel. Be prepared to de-oxidize them for the rest of your life to maintain the shine. Otherwise they start to frost and look like a fuel tank on a truck.

A gardener friend told me people plant things in wrong places all the time and they grow anyway.

I appreciate your taking time to explain the technical details of anodizing, from actual personal experience. I'm convinced it's the right way to do things.

As I'd already done what I did not knowing any better, all I can report (If anybody gives a rip) is the bumper is still looking chrome after a month of rain, there ain't no micro-pitting unless it's so micro I need to get a microscope to see the weeny teeny specs, and I don't anticipate any more frosting than on any other (valve cover, etc.) aluminum parts. Maybe an occasional quick rub and buff with metal polish, no big deal.