#Fastener rules
These apply to every step.
- Every screw is M3, and only three lengths are used: M3 × 6 for the compute-plate standoffs, M3 × 30 for the landing legs and M3 × 35 for the arms. Sort them by length before you begin.
- Every arm and leg screw takes an M3 nylon-insert lock nut. The only screws that don't take a nut are the eight M3 × 6 in Step 5, which thread into the standoffs.
- Snug, not tight. Carbon plates crack and printed fittings split if you overtighten. Run each lock nut down until the nylon collar engages, then tighten until the parts are just firmly together. The lock nut does the rest.
- Tighten in diagonals. Wherever a fitting has several screws, take them all to finger-tight first, then snug them in a cross pattern so the fitting pulls down evenly.
#Connector rules
- Push each bullet fully home. A half-seated bullet runs hot and can drop a motor in flight.
- Pull every heat-shrink sleeve over its joint so no metal is exposed.
- Plug the battery in last, and only for the steps that call for it.
- Props stay off until Step 10. Fit them only after motor order and direction are confirmed, and never with a battery connected.
#Tools
- 2.5 mm hex key or driver (all screws)
- 5.5 mm spanner or nut driver (M3 lock nuts)
- Wrench or socket to fit your motor's prop nut
- Side cutters and cable ties
- Laptop with Mission Planner or QGroundControl, and a USB cable for loading firmware
#Orientation
Front is the end that carries the optical-flow sensor. The XT90 battery lead exits at the rear. The ESC is on the underside of the main plate, and the battery plate hangs below it.