RotorX RX122 Atom V3 - 4"

By wrong17 on Jun 03, 2018

11  653  9

I always wanted to build a RotorX RX122 Atom V3 4" frame because I kept seeing great reviews on it. So here it is, a light 4-inch quad that weighs in around 142g - 150g depending on what props you use. Overall it was a pretty easy build with a HGLRC XJB F428 stack because all I need to wire up is the Motors, VTX, Camera and RX. Initially I was using the stock dipole antenna with the eachine VTX03 but it was not doing as well as I hoped so I switch it out to a TrueRC AXII.

As for the props, It all depends on what you want to get out of your Atom. I like the flight characteristic of the GemFan Flash 4052 but it does weight a lot compared to everything else I have tried. Even with the extra weight it still flies very efficiently, I get about 6 minutes of flight time (depending on the way you fly). I also like how quiet the flash props are compared to the 2 blade Dals. However, the GemFan Flash props are a tad bit larger which has less than a millimeter of clearance between the props. As of now I was able to fly it without any issues or props strikes but it is just too close for comfort. Over all this is a great frame, I know it is an older design, but it just works. So, I will be keeping this setup in my collection for a while.

Update July 2018: 3D Printed Canopy
I liked how this 3D Printed Canopy fit, but I had 2 issues: it’s kind of fragile and heavy. So I end up going back to the original canopy, but this time I modified the camera opening so I can increase the camera angle.

Update May 2019: Another 3D Printed Canopy
I wanted to try using a GoPro Session 5 on the Atom and see how it performs so I finially installed this 3D Printed Canopy that I printed over a year ago. Surprisingly I did not take pictures of the canopy but if you are interested, you can download the STL files here (I did NOT design this canopy):
https://www.thingiverse.com/thing:2155306
Here is a video of the Atom with a GoPro Session 5 strapped to its back.

Photos

Part List

Frame

RotorX RX122 Atom V3 4" Frame Kit (2 builds)
Getfpv.com
$39.99

Flight Controller

HGLRC XJB F428 V2 Stack - F4 Flight Controller - 28A Blheli_S ESC (14 builds)
Getfpv.com
$63.99

Motors

4 x Brotherhobby Tornado T1 1407 3600KV (194 builds)
Getfpv.com
$63.96

Propellers

Gemfan Flash 4052 Tri-Blade 4" Prop 4 Pack - Choose Your Color (13 builds)
Racedayquads.com
$2.99

Propellers

DAL T4045 V2 Tri-Blade (30 builds)
Dalprops.com
$2.49

Propellers

DALPROP J4045 Standard Two Blade 4 Pack (2 CW and 2 CCW) (2 builds)
Twistedquads.com
$0.50

FPV Camera

Foxeer Arrow Micro Pro FPV Camera (Black) - Heli-Nation (2 builds)
Heli-nation.com
$19.99

FPV Transmitter

Eachine VTX03 Super Mini 5.8G 72CH 0/25mW/50mw/200mW Switchable FPV Transmitter (426 builds)
Banggood.com
$12.22

Antenna

True RC AXII-U.FL 5.8 (33 builds)
Pirofliprc.com
$19.99

Receiver

FrSky R-XSR 2.4GHz 16CH ACCST Micro Receiver w/ S-Bus & CPPM (863 builds)
Getfpv.com
$20.99

Batteries

Tattu 850mAh 14.8V 75C 4S1P Lipo Battery Pack (XT30) (34 builds)
Getfpv.com
$18.86

Radio

Team BlackSheep TBS TANGO 2 PRO RC RADIO (22 builds)
Heli-nation.com
$199.99

Goggles

DJI Digital HD FPV Goggles (86 builds)
Getfpv.com
$529.00

HD Camera

GoPro HERO8 Black - Waterproof Action Camera with Touch Screen 4K Ultra HD Video 12MP Photos 1080p Live Streaming Stabilization (14 builds)
Amazon.com
$308.00

HD Camera

Insta360 GO Stabilized Camera FlowState Stabilization Mount Anywhere Hands Free Auto Edit Water Resistant Slow-mo Sport Action V (2 builds)
Amazon.com
$29.99

Video Receiver

ImmersionRC rapidFIRE w/ Analog PLUS Goggle Receiver Module (145 builds)
Getfpv.com
$149.99

Battery Charger

HOTA D6 PRO Charger AC200W DC650W 15A (6 builds)
Pyrodrone.com
$119.00

Soldering Iron

TS100 Portable Programmable Smart Soldering Iron (171 builds)
Racedayquads.com
$51.29

Backpack

Lowepro QuadGuard BP X3 - Drone Backpack for 4 FPV Quad Racing Drones and 15" Laptop w/Exterior Mounts (Black)
Amazon.com
$286.00

Accessories

BoYz analog bay v2 for DJI FPV goggles
Themakerboyz.com
$23.98

Accessories

Analog FPV FatShark Module Adapter V2 for DJI Digital FPV Goggles
Pyrodrone.com
$11.99

Accessories

FuriousFPV Smart Power Case V2
Helidirect.com
See Site
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Discussion

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Yinka_Brasil   Sep 10, 2019  

fantastic build and photos!!! Did you find or can you recommend an alternative/solution to the camera angle drawback you mentioned in one of your comments?

wrong17   Sep 14, 2019 

Thanks! I end up using a dremal and trimming the opening of the canopy and I was able to push the TPU camera mount and force it to stay in place. Before going this route I 3D printed a white canopy (PETG) that allowed me to have any camera angle but it could not take the abuse. I broke 2 of them after a few crashes so I end up going back to the oginal canopy (Blue).

Yinka_Brasil   Sep 18, 2019 

Thanks for the response.

Indy   Jun 15, 2018  

cool quad! Strange they sill call it 122... it's not 122mm at all :D

Oguh   Jun 09, 2018  

The build looks great btw. Do you know if the quad is under 250g with the battery added? If so it would be an awesome build for when the new laws are introduced here in the UK next year.

Show 1 more comment
Oguh   Jun 12, 2018 

Thanks for the reply. Amazing build and its very likely to be my next. The atom frame just looks great

wrong17   Jun 13, 2018 

No Problem, I am sure you will be happy with this frame, it is simple and works great. Only one small drawback.... it does not have too much flexibly with the camera angle. If you have a 3d printer you can print out other camera angles, but it is still a pain to change.

Oguh   Jun 15, 2018 

Ok, thanks for the advice

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