I changed my mind... dont bother trying to suspend other robots (using the hanging method)
http://forums.usfirst.org/showthread.php?t=13726
In my mind, its too risky that you will touch some part of the tower, its not wide enough to comfortably fit a standard robot base with enough wiggle room that hanging from another robot there is no way you would touch it (plus what if you were touching the other side of the platform or anything on the tower... no points). You are better off hanging yourself on another bar for 2 points than risking loosing the three.
(sorry for hijacking, but I dont see the point in spending time on a system like this anymore)