Belt tensioner for Rostock

Use the M8 threaded rod and two nuts on the ends. Supports for nuts are parameterized - modify if you feel it necessary.

UPDATE 19-09-2012: Parts slightly modified. Idler end fits F608 bearing. No bottom endstop - belt spreader instead.

UPDATE 23-09-2012: Modified idler end.

UPDATE 27-09-2012: Modified carrige.