Because balsa, although lightweight and easily formed, is in my opinion the softest and least durable material on the planet for building airplanes. There is a reason modern airlanes are no longer made from wood (comment made respectfully and my opinion only). After 20 years of thinking balsa was what I was supposed to use for model airplanes, I gave up on it, and have been having a blast ever since. Plastic is now my #1 choice, and more recently I've just started experimenting with very simple aluminum fuselage "rail" structures. My first attempt is cronicled here:
http://www.rcuniverse.com/showthread...99&forumid=235
Yes the plane is very crude, but I have found the aluminum to be much stronger and MUCH lighter than I expected. Before you dismiss a plane such as this as being just downright ugly...which I will admit...it is...I think it may be the forunner to some interesting ideas. Although I haven't had the time to continue yet, my next ideas along these lines are to build the fuselage as a "chassie" very similar to a car, where the aluminum is the structural component...and then fashion a non structural fuselage "shell" very similar to how R/C car bodies are done. Also, I've been using close tolerance holes, and fiber lock nuts and bolts to put them together...I've wrung them out, and have had no problems with the bolts losening or slipping.



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