(March 7, 2017) The 3D printed mounts for the Ettus worked like a charm. The construct consists of three parts, two holders that are held into the base of the Ettus USRP via M3 screws and then a mounting / gimbal base that connects to the drone via M2.5 screws. Material was a red ABS (Village Plastics, purchased from Lulzbot).
