This is a flexible coupler between a motor and an axis. Openscad file is provided to change the axis diameters.
Horizontally printed with raft but without support using PLA on Flashforge Finder.
Flexcouplerhex (http://www.thingiverse.com/thing:2288244) is a stronger flexible coupler. Easier to print without raft.
https://www.youtube.com/watch?v=S5aohtCilog