Painting an aluminum boat

[Gulf Comanche]

Greetings All:
It's time to repaint the topside of Old School as what's on there now is starting to flake in spots. I have never done this so I would like advice on what paint to buy. Will surely need to rough up the old paint with a sander. Can paint chips from the current paint be analyzed so as to get the same or similar color? All help appreciated.
Thanks,
Mike

 

[FF]

I have used Rustoleum water based aluminum primer for both aluminum and hard to paint galvanized.

It can be over painted with oil after a few days of drying.

Unlike many primers , it does not seem to require a top coat , 4 years so far.

 

[Larry M]

We painted all the aluminum on Hobo 5 years ago. I think we had ~50 plus pieces plus we painted all the exterior parts of the port lights. We first sanded down to bare metal then washed with Alumiprep 33 and then used Alodine, then a high build PPG epoxy primer and finished with Awlgrip paint. There were a lot more steps in between but these are the basics. As with most painting projects, the level of prep goes a long way on the how the finished product looks and lasts.

Look at some aircraft painting web sites for more information. Planes or parts of them have been painted for a long time. Good luck with your project.

 

[Larry M]

Some befores and afters.

 

[sunchaser]

We painted all the aluminum on Hobo 5 years ago. I think we had ~50 plus pieces plus we painted all the exterior parts of the port lights. We first sanded down to bare metal then washed with Alumiprep 33 and then used Alodine, then a high build PPG epoxy primer and finished with Awlgrip paint. There were a lot more steps in between but these are the basics. As with most painting projects, the level of prep goes a long way on the how the finished product looks and lasts.

Look at some aircraft painting web sites for more information. Planes or parts of them have been painted for a long time. Good luck with your project.

For painting Al, there are many wrong ways and but a few right ways if you desire a quality job. Like everything nautical he does, Larry M nailed it

 

[Gulf Comanche]

Very nice job Larry, and thanks to all who responded. I don't want to go down to bare metal as it would take many hours/days/who knows, etc. I plan to paint over the current paint job and, where necessary in a few places, down to bare metal. My concern is what paint to use over the old paint.

 

[FF]

. "My concern is what paint to use over the old paint."

In most cases a primer is required if the top coat needs to stay stuck to the substrate.

 

[Larry M]

That shouldn't be a problem. You shouldn't have to take everything down to bare metal. We didn't on our mast.

I would assume you have a 2 part paint. You still should sand everything to accept the recommended primer of the paint you're going to use. I'd contact the paint manufacturer.

 

[mbevins]

The biggest mistake people make is not matching the primer to the topcoat and telling the paint MFG that your covering aluminum.

 

[BruceK]

In my limited experience of painting an aluminum windlass cover, exposed aluminum oxidizes faster than a fast thing. You need to get the primer on asap after exposing the surface. Thousands of aluminum Muir windlass covers(new ones are composite) with bubbled paint attest to this.