About this 3D model
To complete this set, I need a triple socket to match the single and double sockets found here: http://www.thingiverse.com/thing:7285 http://www.thingiverse.com/thing:7264 This thing gives you three ball sockets that can be attached to a rod. By default it is designed to slip/friction fit on a 5/16" rod. This thing, combined with various other ball/socket combinations can make for some very interesting structures.