Building out crash kit.

[Atomic Skull]

So I have a couple complete airframes a whole pile of parts for my existing machines, and enough electronics (except for the ESC) to get a second one flying along with several spare sets of blades. So I figured why not.

Cyclic servos are AFRC, 0.4 sec 60 degrees and 25kg-cm and the tail servo is 0.35sec 60 degrees and 22kg-cm. They can run in narrowband mode up to 666hz.

Flight controller is a Radiomaster Nexus, Amain sold them off at a ridiculously low $38 when the newer Nexus X was released, the only difference is that the X version has 9 ports instead of 7. It runs on the open source Rotorflight software.

ESC will be a SEQURE 14200 Pro, it can run either ESCape32 or AM32 firmware. Helidirect sells them with an AM32 tuned by their team pilots for use on large helicopters so that it is plug and play.

Motor will be a Quantum 4530 450KV outrunner I have laying around.

Have the servo wiring done and the servos centered and head geometry set up, waiting on the ESC now.

 

[Atomic Skull]

Wiring and building is complete, rotor head and servo setup is also finished. Left to do is finish the flight controller setup and install an antenna holder, I thought I had one but I couldn't find it so I have to wait for that to arrive. After that maiden hover and pray I didn't miss something or make some mistake in the setup and it destroys itself on takeoff. First test flight of a newly built helicopter is always sphincter tightening

 

[Atomic Skull]

Drivetrain details taken from the manual:

The big 54t pulley with the one way bearings is driven by the motor (it says "reduction gear" but the first stage is a cog belt drive) and then the 20t gear drives the 66t main gear. The torque tube inside the boom is a hollow aluminum tube with three bearings glued to it that are each supported inside the tail boom by plastic snap-over bearing holders and a surrounding rubber grommet. The total gear ratio from motor to main rotor is 8.91:1 and the tail rotor ratio is 4.75 (tail rotates 4.75 times for every rotation of the main rotor) or at 1900rpm the tail will be 9025rpm.