Belt Tensioner, adjustable R2

Latest update here > http://www.thingiverse.com/thing:838003 Revision 2 of http://www.thingiverse.com/thing:677297 Added a recess at the inner diameter of the flange to ensure positive contact between outer diameter portions of the mating surfaces. This makes for a better grip. A simple adaptation of the spring type belt tensioner into an adjustable and rigid form. Fits GT-2 belts. OpenScad files included for your customization.