HangsFromSky batch 3 build log

My notes, observations, musing and ponderings on my batch3 build.

Noob mistake number one: sanded down the short tubing connectors till they just fit through the holes in the legs. Then after loctiting the lower structure together, realizing the metal tubing has to fit over it. Nothing a file can’t fix, but a bit awkward with tubing connectors already in the carbon fiber legs and not wanting to take them apart.

The wires to the motors from the ESCs were probably an inch longer than I would really like them, but I left them as were and just crimped butt connectors and then soldered and heat shrinked.

The ESCs have a strong odor, like burnt electronics, but have not been powered yet. Couldn’t keep them in the house after assembly.

Looking at other build logs, looks like the creative bit will still be ahead: how to attach the batteries.

Looking at some of the more recent two switch wiring setups: why the separate terminal post 4-way junctions instead of just having three lugs on the post of the switch?

I see some have cut off the unused wires of the ESCs. Is this still recommended?

Thinking ahead to order 3d parts: leg hinge stops, precharge switch, maybe a box for the BEC.

what’s the “BEC” ?

Sorry, I was referring to the “frame board/controller” as a BEC.

What are the 8 M4x12 screws for?
Should I end up with a lot of left over standoffs when I am done?
Which screws are used to attach the two switches to the power switch plates? I am guessing the 12 M3 nuts, but only need 8 and the M3 screws are not long enough.

The M4x65 screws seem a tad bit short, should have a bit more thread in the lock nut. Should be at least a half turn of thread protruding past the lock nut,

Wiring done, ready for first power up.
I used a separate momentary pushbutton and 20ohms of resistance for priming.
Checklist must include making sure both power switches are on. The wiring enables 2S1P operation, but really should only operate 2S2P.
I intend to do the first powerup with only one battery and no props. 22V should be enough to verify the motors are spinning the right way and to do the throttle calibration procedure, right?

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First power up did not go as smoothly as I imagined. Three motors spinning one way, one motor the other. That I can fix. But the one motor spinning the other way is behaving oddly, spinning even when finger is off the throttle. I expected to be able to do a ESC throttle calibration, but that does not seem to be working the way I expected. Can the system be armed with the throttle in the down position? I assume the one spinning motor just needs a calibration, not sure how to do that. Will dig through the blogs…

Applying USB power to the base of the hand controller is not powering up the control system. What am I missing? Is this a change in the new hand controller vs the previous generation? If so, what is the best way to do a throttle calibration?

The Arduino in the batch 2 speed controller can be powered up and armed through the USB. I assume batch 3 is the same way. Then you can hold full throttle on while flipping the power switch on.

thanks for another “wiring-picture”!
Also very neat and clean - even tough I’ll be doing it exactly as @GliderPilot , with his pre-charge switch and the caps for the ring terminals, I purchased also a 22 ohms resistor, as he suggested.

I like your solution for running the cables through the arm-brackets (those yellow cable sleeves).
Part of one of the signal cables was cut by the folding bracket, when I did not pay enough attention during my assembly.

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After using a dremel to open up access to the USB port on the base of the hand controller, I was still not able to get it to power up from an external USB power source.
What did work: move the power lead of the frame board/controller to the hot side of the power switch, so it is powered whenever the battery is connected. Depress the button, Turn on the big switch to get power to the motors, wait for a double beep, let go of the button. Now all four motors are responding correctly to throttle inputs. Disconnect battery, move frame board power lead back to cold side of power switch.
Just need to reverse one motor and I should be go to go.

That’s correct, the batch 3 controller isn’t set up to accept power from the USB port.

I think I am done with the construction and bench test, except for figuring out a way to mount the batteries that makes me happy.
Things I needed to buy to get here: some extra 8g wire, 8g crimp rings, 10g crimp rings, heatshrink, a momentary switch, some wiring loom and smaller crimp rings, 10g crimp butt, a plastic box for the frame controller, and a 1/4" terminal post. two 10 ohm resistors. I had to fabricate a mount for my monetary priming switch. Some double sticky tape to hold the plastic box in place.
This is the extra hardware I had left over from the kit, for comparison with others that got a batch 3 kit. Let me know if that seems like too much and I probably missed some critical step.

Posted too soon, have not yet attached the motor standoffs and props. That will use up some more of that hardware…

Put the legs on it, stood it up unfolded in all its glory, start thinking about battery mounting options, and realized I had it wired upside down. The power leads go through the backplate at the bottom, underneath where the batteries would mount, when I was intending for them to come out on top, above the batteries.
Take it all apart again to look at rewiring it…

My second attempt at a wiring layout. The positive battery leads go through the holes on both sides, the negatives through the hole at the top. Make sure there is plenty of slack for the wire bundles going through the hinges.

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Protecting the thin carbon rings at the ends of the arms from damage: cut up some 3/4" ID thick vinyl hose.

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Did you glue them on?

I was intending to glue them on, but found that the natural curve of the tubing holds them on pretty well. If they fall off in use I will make new ones and glue them on.

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