http://www.valleytech.k12.ma.us/Robo...2005UCFReg.htm
if you go here we used 60mm x 30mm for the tower and 30mm x30mm for the arm. it was very strong and used a special delrin. we had no problems with the sticking.
You can see we went vertical and horizontal with this system.
we went out 36" from the front and went up 14'