I imported elbow.stl into freecad to rotate the elbow y axis by 180 degrees so the that flat of the large pulley was flat on bed. I then exported to a new file that I called elbowRotated.stl The pulley is the large circular disc with teeth if that helps. You should be able to use any cad package. In that orientation, it minimises the number of tree supports to mostly internal support.
I am using a flashforge 3d printer, the software for that usefully then makes sure the widget is centred on printing bed as well as sitting on printing bed.
This reply was modified 2 weeks, 3 days ago by Asterion.