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PAINTING ALUMINUM FOR OUTDOOR EXPOSURE

1999

I am building a saguaro cactus like sculpture using 1/8" aluminum fins which are approx. 4" wide X 10 ft long. I need to find a way of painting the mill run aluminum black. What kind of preparation, primer and finish coat(s) should I use so that the paint will stay on in an outdoor environment for at least 25 years?

Any help you could provide would be most appreciated.

Stan Price

A. I am not exactly understand your phrase mill run black but I believe chromate conversion coating by any kind of application (brush, spray, or dip) will solve your problem. If you need more details please don't hesitate to ask.

Yehuda Blau
YB Plating Engineering and Quality - Haifa Israel
1999

A. I really doubt if black chromate would last 25 years, even in Arizona. Probably the best guess is a highly UV resistant powder coat paint. Black chrome plating is another option, but not many "black" shops have huge tanks.

James Watts
- Navarre, Florida
1999

A. It really depends on what outside wear the aluminum will have. I use a variety of high-end urethane enamel car paints with the UV protectors built in, and I use a number of clear coats on bare metal as well. For blacking, you can also use a product from Birchwood Casey, Aluma Black ⇦[Aluminum Black on eBay or Amazon [affil links] , for blackening, and a clear over the top. This is all assuming that the sculpture would not have anything other than the normal wear of a car surface. I would be interested in what you decide on. Thanks, Tom

Tom Brumm
Blue Rock Studio - F.H., Washington
1999

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I have a lawnmower type pulling tractor which I am repainting for a friend. It has an aluminum hood and grill. How do I prepare the surface so primer and paint will adhere to it?

Leo Fronczkiewicz
Motorcycle painting - Douglas, GA, USA
2005 -- appended to this existing thread by editor.