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[Hawiian Cadder]

We used 3*1.5 inch tubing with .125 thick walls and a special hole pattern cut into it this year. 3/16 rivets and grade A 10-32 Button-heads are our fasteners of choice. This year the drive frame weighed 10lbs, and the entire frame weighed less than 16lbs. If you have the machining resources to do it, I would look at perforated tubes as a construction method, I cannot think of a way to make a lighter frame. For some examples check out team 40 or 111's robot from 2011