There is so little thread on these motors to engage with, beside the fact 3.0mm bolts are decidedly fiddly anyway, that the easiest solution is to drive the bolts in from the far side. To do so without impacting the windings I've reduced the shanks to 33mm, which in turn means they've probably cross-threaded the bolt-holes on the base of the motor. At the same time I've had to pritt-stick a washer in place to ensure the axle protruding from the base clears the frame. All in all a parlour game which keeps a whole family amused throughout the whole of Boxing Day.
Does though demonstrate the versatility of the design, because from hereon in we can simply flip the drone over to proceed right-foot forward. Alternatively we can leave it as intended and leave the motors mounted inverted on the underside of the airframe. Either way it looks like plastic pushes the envelope when it comes to rigidity, which is why we shall retain an alloy backup for the perimeter sections at least.
I've decided to leave the full length of the cable intact, not least because it saves re-soldering the ends... the cable-tidy was made by wrapping the excess length around a length of double-sided tape stuck to the frame.
A feature of drones which helps all of this is that ~ with computer control ~ it doesn't matter if the motors are not mounted perfectly level. Any tendency to wander due an offset in their level will be remedied by adjusting the RPM of the remaining motors to restore a level hover... something the pilot would have had to do in Christmases past.
