was designed for a friend. the knuckles are opposite each other in order to allow the end user to place the items together. when you upload the stl. for somone it comes out huge. so attempt to scale it down to 3 and you should end up with the prints in the image. now looking at the image the blue one was printed on my type a machines series 1 version 2014, still working on the kinks that this printer has some how developed. and the purple one was printed on my lulzbot series 5 and its looks great.

If for some reason you can't slice the file msg me and ill upload a gcode specific to your printer on my simplified 3d app.