I had some difficulties after printing this model: http://www.thingiverse.com/thing:253934/#files Had to design some parts on my own for different reasons: 1) Some pieces when placed into position made other pieces slip out so I designed pins with longer "thin" part. 2) I had some friction so the original shape of the handle didn't work for me. 3) I also had to make the handle gear bigger. Hope you find it useful!