I’d be happy to share the full build list for my 3.5" Arducopter beater.
The build goals were:
- Arducopter firmware
- Sub 250g AUW
- Sub £200 (excluding battery)
- High performance
I used the ImpulseRC Micro Alien 4" frame with 1604 motors and 3.5" props. Performance is very good and autotune gave a tight tune. The biggest limitation is that the GPS and compass performance is compromised by proximity to the VTX antenna, battery lead and capacitor. It can loiter well and do high speed auto missions, but I’ve yet to refine the WPNAV parameters for smooth fast-ish auto missions.
The advantage of the Micro Alien frame is that it’s light (~35g) and compact, but it is a tight build and only really suited to a 20x20 stack and analogue VTX. Weight is 152g dry, 233g with a 4S 650mah LiPo.
I imagine the 3" variant with 1404 motors would also perform well.