I wanted a Fan Mount that wouldn't cap my Printsize and isn't pointed directly at the printbed. Bieng inspired by http://www.thingiverse.com/thing:36300 and http://www.thingiverse.com/thing:299659 i designed my first OpenSCAD object from scratch. If you want to make your Personal fan mount you've gotte do some math before. The distances are measured from the center of the Rod to the inner Mounting Pin. So for the width of your arms you've got to know the distance of your frame rods and the position of the holes in the Fan for which I found this picture quite helpfull. http://s407.photobucket.com/user/mcintyregreen/media/fan.jpg.html