Aluminum boat finish

[Gbrent]

Hello all, I am looking for opinions and hopefully some consensus on the best method of dealing with 2 issues on an aluminum boat exterior. The boat is an ex lodge boat that spent what looked like a considerable amount of time in saltwater, resulting in many kinds of marine growth and general nastiness below the waterline. I had it professionally pressure washed at Stones boatyard last year. Results are much better but, I still have some barnacle rings, discoloration and being an ex lodge boat obvious ghosting where vinyl lettering was. My thinking is to perform one of the below procedures this spring… My Intent is to find the best process to clean up the two issues and leave the aluminum in the most natural state possible so it can oxidize naturally. Not wanting a hull that is whitened or too rough, etc. Hoping both issues can be tackled in a single procedure. Boat is trailered unless being used so bottom paint is not needed.

1) Blasting – A) sodablast, B) dustless blast with crushed glass, C) conventional blast with softer media like walnut, etc

2) Chemical clean – A) AlumiBrite or other chemical cleaning process

From what I have read, chemical cleaning should clear up discoloration and barnacle rings but, I do not know the effect if any on the ghosting issues. A possible negative to chemical cleaning is it leaving an obvious white finish that will then need to be dealt with in second procedure. Blasting should work on both issues but can result in a rough fishing that is good when bottom painting a hull but, not great if left in a natural aluminum state.

Opinions and pictures of peoples past experiences regarding these boats would be appreciated.

 

[Gbrent]

Example picture of ghosting mentioned above... Not mine but should give you an idea.

 

[Nakoda boater]

Example picture of ghosting mentioned above... Not mine but should give you an idea.

Media blasting would clear and clean everything up.

 

[ericl]

I'd call the mfgr - I'd use an AL buffing compound before the other 2 options

 

[kevind]

Why do you need a second procedure after acid etching it? The white finish will start to oxidize and turn gray over time. Also the amount of white finish depends on the concentration used of the acid from what I have read. I will be doing the inside of my boat soon and should have some first hand experience with it that I will detail in my forum post.