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  for Metal Finishing since 1989
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Removing heavy corrosion from aluminum aircraft

I own a Cessna 150 1967 that has a plan metal finish. That finish is badly corroded. The corrosion is like a crust. I have used 360-grit sandpaper [affil links] to cut through it. Once crust is removed, subsurface seems to be ok. I have rivet heads that protrude above the flat surface. Rivet heads cannot be sanded. I have used an aluminum chemical truck cleaner that did remove some corrosion. Is there a chemical process that will remove the corrosion chemically? It would be a big help in cleaning around rivet heads. Originally I was going to use Alodine 1100, then polish the aluminum. If the surface is not good enough to polish, then paint will be the next option. Any information you can give me would be appreciated.

Thank you,

William John Koenig
hobbyist - Benedict, Maryland, USA
2004

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You can try this simple formula:
25 gms sodium carbonate ⇦this on eBay or Amazon]
25 gms 'water glass' ⇦this on eBay or Amazon [affil links]
1 lit water

Good luck!

Goran Budija
- Cerovski vrh Croatia
2004

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Mr. John Koeing:

Sounds like you have a serious case of corrosion in your hands. Considering you are talking about an aircraft, I would reference you to the FAA (Federal Aviation Administration)Advisory Circular (AC)publications. AC43.13 gives you a general view of typical "Repairs and Alterations", and specifically AC43-4A "Corrosion Control For Aircraft". Remember,these are 'advisories' only, and the information contained in these AC's is applicable to aircraft for which the manufacturer has not published corrosion control information, if they have, the manufacturer's corrosion control program takes precedence. You can probably access these two AC's through the FAA's web site, www.faa.gov.

Best wishes "."

Rusy Soria
- Norwalk, California
2004