Anodized Aluminum Moldings

69 Rustang said:

What can be done with anodized aluminum moldings? I have a set for my 73 that just look nasty and won't just clean up. They can't be polished unless you sand off the anodizing, which on roof rail moldings can be done, but windshield and back glass moldings are another issue. I know I can replace them, but dont want to spend the $$$ .

Can they be re-anodized? The only other option I can think of is to paint them but then it is not correct.

Click to expand...

it's actually a process called Bright Dip anodizing and yes it can be redone. the windshield and back glass moldings should be stainless steel actually and that can be polished.

Aluminum can be anodized more than once, but it involves stripping the old stuff and that usually means an acid dip. Anodize is an embedded oxide layer and the base metal will get thinner whether you sand it off or acid dip.

What does it cost for new ones? Many anodize/plating shops have a minimum price and big/awkward items can sometimes drive the cost up.

I assume the stock moldings are clear anodized, right? No color?

You may want to check with some plating shops in your area. they may have a reference for a source. that's how I found a company to do so anodizing for me

I don't think you'll be happy with bright dipping long term. I work for a company that uses bright dipping, soft annodizing, hard annodizing, and HA with Teflon. Hard annodizing hold up to chemicals and wear & tear a LOT better than bright dipping.

just my $.02

ericl said:

I don't think you'll be happy with bright dipping long term. I work for a company that uses bright dipping, soft annodizing, hard annodizing, and HA with Teflon. Hard annodizing hold up to chemicals and wear & tear a LOT better than bright dipping.

just my $.02

Click to expand...

bright dip, is what these cars had from the factory. if you don't bright dip the part you have to have it polished first and that can get real expensive and most polishers won't guarantee that they won't bend the part when polishing at least with aluminum

bnickel said:

bright dip, is what these cars had from the factory. if you don't bright dip the part you have to have it polished first and that can get real expensive and most polishers won't guarantee that they won't bend the part when polishing at least with aluminum

Click to expand...

Maybe I've just been lucky with mine or the P.O. replaced everything. It has been my experience that bright dipping only cleans the part and does very little to protect the surface. While anodizing to whatever spec gives the corrosion and abrasion resistance. As for polishing, if you're going to go to the trouble you might as well go all the way. Do you want a shiny part or a shiny part with scratches? If 69 Rustang is bright dipping on top of a bad surface the I don't think he will like the outcome.

Here is a section from a website on andoizing.
"• Pretreatment is used for decorative purposes – to improve the appearance of a surface prior to the anodizing step. The most common pretreatments are etch and bright dip. Etch is accomplished in a solution of caustic soda (sodium hydroxide). The etch imparts a satin, matte finish by dissolving aluminum from the surface in a microscopically irregular pattern. The bright dip process takes place in a bath of mixed acids that impart a bright, shiny finish by dissolving aluminum from the surface in a manner that levels the microscopic peaks and valleys. After etch or bright dip, it is a common practice to dip the metal in an acidic desmut/deoxidizer solution to remove any residue of alloying agents or oxides.

• Anodizing is the step which produces the actual coating. It is accomplished in an electrolytic cell using sulfuric acid as the electrolyte. The item to be anodized is made the positive electrode, or anode (hence "anodizing"). When direct current is passed through, water is decomposed, liberating oxygen at the surface of the item. The oxygen combines with the aluminum to form the coating – a transparent and microscopically porous layer of aluminum oxide. The coating's thickness is determined by the electrical current and the length of time it is applied."