So, after some misconfigurations I installed the 2.18 for the F421 ESCs. I thought I messed one of them up when the configurator 1.82 chrashed half-way through a firmware update, but it seems all right now.
Had some issues like motors spinning all in the same direction after the change, PreArm: Internal errors 0x800 l:279 watchdog_rst, and others. All cleared now. And now I have these settings:
This isn’t right for Bdshot motors on the Aux outputs you have configured.
SERVO_BLH_BDMASK,15
Ahh, yes should be SERVO_BLH_BDMASK 3840
Test flight in high winds with perhaps somewhat extreme parameters intended to achive high speeds into high winds with gusts. It seems BdShot is only partly logged. I’m close but missing something here like - LOG_BITMASK?
The drone is tearing into the air @ 0.15 for MOT_THST_HOVER and I barely touch the pitch forward to achive good speed into 12-13ms winds
Now that you have the most basic of things configured you should follow some tuning strategy. The Methodic Configurator may be best suited for you unless you know how to manually tune.
A couple of other comments:
The vibration levels are extremely high. Clipping events, which you have, on a flight controller like the 6X with isolated IMU’s is all you need to see. You really can’t advance before dealing with that.
Configure back to Dshot600 now that you are on the Aux outputs.
Thank you so much Dave. I hadn’t realized how awesome these proper configurations are until now. I’ll reconfigure for DShot600, relax the extreme weather params and catch the next calm weather for a tuning flight.
I’m going to rig up another drone just like this one and use the Methodic Configurator from the start. And keep messing with this one manually. This is a scientific case-study now (‘-’)
The vibrations are a problem. Post-mortem after this flight shows that the armholder connectors are coming loose. One of them on this flight. This prototype still has the aluminium arm holder and connector, that seem to come loose because of thermal expansion/retractions, or excessive forces in heavy weather.
A 3D printed carbon alternative screws much tighter and holds better.
I’ve also added some rubber gaskets and anti-vibration pads for the flight controller. But I’ll have to do another test flight with the motor arms tightly secured to ascertain the current status.
Ahemm. I just chrashed it. Seems like one of the ESCs or Motors failed. Came down from 150m spinning as on three motors. One arm broken. Minor damage.
I only changed MOT_PWM_TYPE to 6 for Dshot600 but I’m seeing strange logs for ESC as they are only three and not numbered 9,10,11,12 but 8,10,11
Seems like I overloaded the PDB or ESC
I’ve got another one that’s somewhat bigger…
(‘-’)
Rebuild is complete 
Hey there Dave.
And thanks again for your advice. Haven’t had time to get back to this one until now. Remember that horror vibe show? Looks somewhat better now
Vibe test in heavy weather. Basically a redesign of the frame with softer and less rigid materials. Vibration cushins in the form of fibre-rings, TPU-95 components, and a special 2-part silicon component. Very happy with the result.