...stated very clearly the DISadvantages of aluminum for things like suspensions! It was in a marine-engineering magazine, but it covered a lot of the disadvantages of aluminum--even in old cook-ware! Despite the tremendous range of tensile strength etc. available in different grades of aluminum, the authors said that even with numerous safe guards (shock settings, spring-rates, the tires-acting-as-springs [they do!] effect, etc.) aluminum suspension parts would either deflect without 100% rebound or simply fatigue, especially around bushings and mounts. Gives one pause when we see everyone from Corvette to Audi rushing towards aluminum suspensions. About the only aluminum "frame" I would look at is Herb Adams' VSE ("very Special Equipment"). It looks like it will do! I dunno if he's still making them, but they were awesome for things like rigidity, etc. FFR started making aluminum frames (despite people saying that they weren't, they WERE! I think that idea went quietly away.
It might pay to talk to vintage aircraft rebuilders. Practically all the "warbirds" racing and displaying aeronautic stuff nationally have had their aluminum main "booms" (guts of the wing strut system) replaced.
My advice on a standard tube (non-monocoque)aluminum frame is----DON"T DO IT!
