In article ,
"Morgans" wrote:

"Lou" wrote in message
oups.com...
Ok, but why do I want to coat the aluminum? Is this a process just for
metal planes?
should i be doing this on my aluminum hinges attatched to my wooden
spars?


Aluminum will oxidize if left to it's own means. What the etch - alodine
coat process does is prevent the process form continuing on it's own.


Aluminum protects itself. When it rusts (aka oxidizes,) which it does
very very quickly, it forms aluminum oxide (duh.) A coating of aluminum
oxide is about the hardest, most impervious thing you could put on a
piece of metal. The "process" does not "continue on its own." As soon as
a microscopically thin layer forms, your aluminum is protected from
further degradation.

The problem arises when the exposed metal is left to water, salts,
dissimilar metals, etc, for long periods of time, which sets up
electrolysis. If you think you're going to protect aluminum from that
kind of damage with some kind of coating, then be my guest. I plan to
keep my plane clean and dry, and let the aluminum oxide that forms
naturally do its job.

Now, I know Mr. Morgans isn't going to flame me for these comments,
because he's already canned me, but I'd love to hear from others who may
disagree.

Jon in California