Mavic X-knight

By Hyperflyt on Nov 22, 2022

4  87  2

X-knight naked vista polar with dji mavic mini motors.
TLDR, Beta FPV X-Knight frame with custom cut arms to mount Original DJI Mavic mini motors. Mavic mini motors are terrible quality and induce way too many vibrations and begin to fall apart. There are better modern motor options that will deliver better performance, efficiency and quality.

This was my atempt to build a sub 250g toothpick style digital drone using the original mavic mini drive train. I custom cut the betafpv X-knight arms to accomadate the V1 mavic mini motors. My intent was to match the flight time and increase the maneuverability of the original Dji Mavic mini using the same motors and a custom built 2S li-ion battery.

Dry weight 131g
w/battery 238g

At first I used the original mavic mini propellers and quickly realized that the props were way too flimsy and offered poor flight performance.

Second issue I ran into was the overall terrible quality of the original mavic mini motors. They introduce tons of jello inducing vibrations and theres really no way of getting rid of those vibrations. I'm pretty sure this is the reason the mavic mini's camera/gimbal is soft mounted with dampeners to cut out vibrations in video.

I did manage to get the craft flying pretty decently using stiffer propellors from some 5" gemfan floppy props, but the extra weight of the props didnt help much with the jello inducing vibrations.

The last remedy was to print an adapter and use some light weight 5" bi-blades which I think were also gemfans and that cut the vibrations in half, although still not good enough for my liking.

After several test flights the motors themselves started to fail, the press nut that holds the motor together would fall out or loosen up causing the motors to sound extra crunchy and induce even more vibrations. I also believe the fact that there is only one bearing in the motor contributes to this issue.

I originally bought all four motors for about $16 US and thought it would be a fun project, but since then the original seller I purchased them from have increased the price making them less desirable for this project. I could easily snag a new set of modern motors with much better build quality for the same price.

Ive purchased some 2004 motors to test out and will update on the results. Ill also link the stl file to the canopy.

Photos

Part List

Frame

BETAFPV X-Knight 5
Dronecosmo.com
$24.99

Flight Controller

JHEMCU UPDATED GHF411 PRO AIO F4 OSD FLIGHT CONTROLLER BUILT-IN 35A BL_S 2-6S 4IN1 (30 builds)
Pyrodrone.com
$58.99

Propellers

Gemfan LR5126 2-Blade Propeller (Set of 4)
Getfpv.com
See Site

FPV Camera

Caddx Polar Vista Kit Starlight - DJI Digital HD FPV System (2 builds)
Newbeedrone.com
$139.99

Receiver

TBS Crossfire Nano RX FPV LONG RANGE DRONE RECEIVER (1350 builds)
Pyrodrone.com
$24.95

Batteries

Sony | Murata VTC6 18650 3000mAh 15A Battery
18650batterystore.com
$6.99

3D Printed

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Printables.com
See Site
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Discussion

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dafunk   10 days ago  
1

nice build ! I was going to build on the same frame a year ago but finally went for the unibody equivalent Twig ET5 made by RacerX.
I started small motors like you than went for bigger 2004 and I am much happier now.

Also thanks for the feedback on the motors, I was considering getting them but now that I know they are so bad I can look for something else.

Welcome !

Apeian   11 days ago  
1

Nice work for your first post on the site bud...Welcome! ;)

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