Now what you really want !
It's not designed for use under automotive or aircraft finishes and no where near as good as a two part epoxy. I have used all of the rattle can primers and I think the best by far is Dupont 4115s. About $10 a can with a special tip that gives a nice fan.
The Sherwin Williams stuff is good, NAPA 7220 is pretty much the same stuff and they are all $6 - $10 a can. SEM makes a nice selfetching primer and so does Plasti-Kote. Most all of the rattle can stuff can be wiped off with a rag and lacquer thinner meaning that it is soft and designed to increase adhesion not for real protection.
Most folks agree that the alcad doesn't really need much so the rattle can is fine if you want to go that route but you might as well use the right thing.
Wouldn't suggest anything less than something designed for aluminum like the Dupont products or other auto finish products that are made for a subcoat under the final finish.
Check with your local auto refinish store.
Just my .02
Bill S
7a finishing
