Someguy's 3" Baby Alien

By Someguy on Aug 26, 2018

7  704  1

And here comes my third build. After having built two quite powerful micros already, I wanted to build something slightly bigger that would be able to take 1080p footage. So I decided to build a 3” that could give home to a Runcam Split mini.

First, I ordered the Forester F130 frame from Banggood. The description said that this one could take 3” props and a reviewer was delighted that it could accommodate two stacks, so this sounded perfect for this little project. However, the quality of the frame was not what I expected. The side plates were too high, leaving a gap between the standoffs and the top plate and there was simply not enough space to spin 3” props. I’ll keep this frame as a spare in case I break my 125mm build.
The frame I used in the end looks like a shrunk-down Alien and I like the looks of it very much. It can accommodate only one stack, so I had to make it as tight a build as was possible. I just had to be a bit creative with how to stack the four boards (4in1 ESC, FC and two boards for the camera). Overall, the build went together fairly easily, but I could not use all eight standoffs that come with the frame to make it extremely sturdy. One set I could not install due to the solder pads of the 4in1 ESC being in the way (pads are oriented front & back). Unfortunately, the top plate was showing in the upper corners of the HD footage, so I filed that one down a bit and worked a little on the side plates to fit the camera a bit further out the front. Downside to this is of course a little less camera protection, but this should not be too much of an issue, as I’m running reverse motor directions, the props should sufficiently diminish the power of frontal impacts.

The weight of this build is a bit on the heavy side, coming in at 155g dry. However, the motors are powerful enough to deal with this and to be honest, I do like the inertia this adds when throwing this thing around. I tested the setup with different lipos (3s: 850mAh, 600mAh; 4s: 850mAh, 450mAh). On 3s it is a bit of a docile flyer, but still has plenty of punch to come out of steep dives. For me personally, this build really shines on a Tattu 4s 850mAh lipo, although this results in an all up weight of ~265g.

Photos

Part List

Frame

ZJW.RC 136 3mm Micro Brushless Carbon Fiber Quadcopter Frame Mini quad fpv racing quad similar with Micro alien QAV-R QAV-X RX22
Amazon.com
$17.48

Flight Controller

HGLRC XJB F438 V2 20X20 F4 FLIGHT CONTROLLER OSD / 38A BLHELI_S ESC (2 builds)
Pirofliprc.com
$64.99

Motors

4 PCS BrotherHobby Tornado T1 1407 3600KV 3-4S Sans Balais Moteur CW pour FPV Courses Drone RC (5 builds)
Banggood.com
$56.73

Propellers

2 Pairs Gemfan Flash 3052 PC 3-blade Propeller 5mm Mounting Hole for 1306-1806 Motor RC FPV Racing Drone (28 builds)
Banggood.com
$3.47

Propellers

HQ Prop 3x3x3 PC Durable Tri-Blade 3" Prop 4 Pack (5mm Shaft) - Choose Your Color (13 builds)
Racedayquads.com
$2.99

Propellers

DALPROP CYCLONE T3056C Props for FPV Racing ***Choose Color*** (16 builds)
Pirofliprc.com
$2.49

FPV Camera

RunCam Split Mini FPV Camera / HD 1080P 60 FPS Recorder (57 builds)
Getfpv.com
$79.99

FPV Transmitter

RunCam TX200U Micro 25-200mW VTX Backpack for Micro Swift - U.FL (14 builds)
Racedayquads.com
$11.39

Antenna

Aomway RHCP 3dBi 60mm Short Antenna FPV 4-leaf Clover Antenna A Pair SMA/RP-SMA for TX RX RC Drone (7 builds)
Banggood.com
$10.59

Receiver

FS-RX2A Pro V1 2.4G Compatible Receiver for FS-I6 FS-I6X FS-I6S FS-TM8 FS-TM10 FS-I10 Transmitter (13 builds)
Banggood.com
$15.99

Batteries

FlexRC FPV Racing Drones | FPV Multicopter Store | Quadcopter Parts (101 builds)
Flexrc.com
$52.50

Radio

FPVracing.ch (10 builds)
Fpvracing.ch
$89.00

Misc Parts

3PCS 50mm ImmersionRC Tramp HV Accessory Pack U.Fl to SMA Female Connector Adapter Cable
Banggood.com
$5.99

Misc Parts

5 PCS Super Loud 5V Active Alarm Buzzer Beeper Tracker 9*5.5mm for RC MultiRotor FPV Racing Drone (33 builds)
Banggood.com
$3.17

Misc Parts

PANASONIC 1000UF 35V LOW ESR CAPACITOR (15 builds)
Pirofliprc.com
$1.05
Show stores (7)

Discussion

Sign in to comment

jetsmack1612   Feb 27, 2019  

what is your flight time on 4s?

Guides & Reviews

Jun 21, 2021

AirbladeUAV has done it again and this time they've brought long range to the 5" class! Based on the popular Transformer Mini, the new Transformer 5" Ultralight adopts a lot of the same design philosophies with larger props and more payload capacity. It can fly upwards of 20 minutes on a 4 cell Li-Ion battery pack and in ideal conditions it's got a range of over 4 to 5 miles. In this guide I'll walk..

Read more
Mar 04, 2021

With the release of the DJI FPV Drone cinematic FPV has become a lot more accessible, but you certainly don't want to crash a $750 drone! The QAV-CINE Freybott is a compact, lightweight cinematic FPV drone that can take a hit and keep going. It's a lot safer to fly indoors and around people. With a naked GoPro or the SMO 4k you can capture some great stabilized footage. In this guide I'll show you..

Read more