We are in the process of putting 0.32 5052 panels in our Caravel
Part of the ceiling and about 70% of the interior side walls. The 5052 that I bought has a coating on it but do I need to have the sheets anodized to prevent discoloration?
Find out what the coating is and how permanent if is. There are many stories of forum members installing raw, in coated aluminum on their interiors only go find that every fingerprint becomes a permanent smudge. Some have recommended wax, some of us have tried spraying clear coats once the sheets are in place. This is what I did, and got marginal results, like many others. The coated sheets that are installed at the factory have a plasticoat on them from the supplier. These sheets are available, but the price is staggering.
Clear Alodine or Chromate Conversion. Check it out, looks like you could do this yourself.
Certainly not a robust as anodized, but for interior surfaces should do well. At HP there was many aluminum sheet metal parts coated that way and they held up very well for many years.
I got lucky and found a shop that is only a few miles from me that can anodize a 10ft x 4ft sheet.
This will give me the hard surface that we are looking for.
Clear Alodine or Chromate Conversion. Check it out, looks like you could do this yourself.
Certainly not a robust as anodized, but for interior surfaces should do well. At HP there was many aluminum sheet metal parts coated that way and they held up very well for many years.
Both answers are correct; anodized is best, and alodine is good.
If stress is involved, see if shot-peening is doable.
(A retired aircraft A.M.E.)
Many degreasers are actually be chemically active on aluminum since it is so highly reactive - translation being if you use the wrong degreaser then the next process steps like Alumaprep & Alodine will be ineffective as the molecular pores of the aluminum have already been passivized by the degreaser but with the wrong bonded molecule(s) than those the other steps are designed around.
Degreased meaning a water film wets the entire piece without any fingerprints or other oil/wax causing the water to resist complete wetting, a film instead of sheeting.
Where I ran into this was cleaning the exterior shells interior trying to get all the cooking fumes and forty years of molds/mildew and oxidation off, yes I found a cleaner that sure brightened the metal up but when I did the alumiprep33 & alodine the alodine did not color change the aluminum (there is a colorless flavor too) at all when it should have been a very light gold/orange/tan.
Repeat after me: Use "Simple Green EXTREME" on bare aluminum.
Applied correctly phosphoric/chromic acid treatment like Alumiprep33 with Alodine seal the metal surface almost as well as anything short of anodizing, which then provides a decent bite for paints or clear coating or waxes.
__________________ The days are short and the night is long and the stars go tumbling by.. . ~Airstream~
This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.