pic: Team 399's arm after the SD finals match 1.

[MrForbes]

Use thick wall square tubing at the ends, thin wall round tubing in the middle?

I don't really have many ideas for using aluminum, both of the arms we've made were built with round plastic tube.

[Ether]

Originally Posted by artdutra04

Looks stressful.

and strainful....

[AdamHeard]

Originally Posted by thefro526

An unlighted 1/16" version would probably be stronger, but the question is, can you get the correct tubing size in 1/16" wall? I've been looking for tubing for our arm redesign, and usually only 1x1 and .75 x .75 tube come in a 1/16" wall.

You can actually get 1.5" and 2" in 1/16".

[Gdeaver]

Put some fiber in your robots diet and go composite. Like pultrusions. However be aware that construction methods for composites differ from metal.