h2o,

What the acid etch/Alodine treatment does is it puts a uniform oxidation layer over the entire pice of aluminum. It's a hard, ceramic-like layer, so in essence just the acid etch/alodine treatment protects the aluminum from further wear/pitting.

I etch and alodine my boat about every 5-6 years and it looks just like it did in 20 years ago. Put some wax on it and it will be much easier to clean, though.

I sell aircraft parts.....one of our lines being an aircraft covering/painting system. We teach classes on how to cover and paint your airplane, so I'm pretty familiar with primers/paints/prep chemicals.
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She was standin' alone over by the juke box, like she'd something to sell.
I said "baby, what's the goin' price?" She told me to go to hell.

Bon Scott - Shot Down in Flames