: I'm interested in building my next boat using a central aluminum rectangular
: tube. Any ideas for a source, and recommended size?

Hi Tom,
I agree with Daren, 6061-t6 aluminum is the the way to go. The t6 heat treat makes the beam quite rigid. I am glad I used the aluminun beam, it is dead straight and stays that way, no matter the humidity or tempature. I used a 2x4x3/16 beam that I bought from a local fabrication shop rather than a metal supplier. It cost me less than making a plywood box beam. I attached everything by drillng and tapping holes for machine screws. The beam was sprayed with blue layout fluid and all layout marks were made with a carbide tiped scribe. If you need more set-up info, E-mail me.

Larry C.