Aluminum from 1957, none the less Scottm2012, Birch, I was thinking giving it a undercoat to help protect the aluminum when coming up on gravel. Sorta like bed liner but without the texture to keep it smooth and still plane well. This boat is reg. to hold a 35 h.p. but will never probably see anything above a 9.9. It is old and heavy but does tread the water nicely. 1957 Feathercraft converted.
I have a 1959 Wagemaker Wolverine (Aluminum edition). Aluminum is a tough metal to paint and maintain. Layers will help but beaching a "paint job" will always scratch or damage the paint. The best thing to do is create a paint job that is easy to touch up. The base coat on aluminum should be a self-etching primer, this creates a base for the top layers of paint to adhere to. Rustoleum makes a good self etching primer. The top coats (at least 5)can be as simple as spray from the can, a professional job, or something in between like Majic Town and Country Implement paint from Tractor Supply (yes, its roll-on).