I modified the body and bottom tray of this great design because I wanted to use fasteners instead of zip ties to keep it together. I created "pockets" on the body and the bottom tray in which M3 nuts can be inserted. Then I also incorporated small structures inside both parts (body and bottom tray) through which M3 fasteners can be installed. The top plate was slightly modified to include the holes for the new fasteners.
The bottom tray was also modified (made higher) in order to fit the 4 30 Amp ESCs that I (incorrectly) chose for this quad. I removed the air inlets on the body because my Printrbot-like Reprap was having difficulties printing them (also the body became more rigid without those holes and refrigeration is still OK).
Printed in ABS at 40% infill and 0,35 layer height.