BETAFPV X-Knight 200mm Toothpick 5" w/ Caddx 4K Tarsier

By wrong17 on Mar 05, 2020

22  967  0

I end up getting a 20a AIO Whoop board that I did not use, so my buddy suggests building a 5” quad with a BetaFPV X Knight frame. Since I record every flight I make, and I hate the quality of the DVR footage and carrying a GoPro defeats the purpose of a lightweight quad. I thought a Caddx Tarsier would be a good compromise.

My motor choice is based on what I have on hand. I have a few choices to choose from, but I will start with the TMotor F30 2800kv (1806 size motors). I am a bit worried about the high KV on these motors, so I hope it does not draw too much amps. If those motors do not work out, I will use try some DYS BE1806 2300kv motors. And my last resort will be DYS SE2205 2300kv motor which I am trying to avoid because it 30g per motor. Where as the F30 motors are 20g and the DYS BE1806 motors are 23g.

The next problem I encounter is how to mount the BetaFPV Tarsier 4K canopy on the frame because none the holes line up to anything. I am not good at 3D modeling, but I manage to create an adapter and 3D printed in TPU.

As for the frame, I really like how you and truly remove 2 screws to replace an arm. The FC is on a plate that is on top of the arms so none of the mounting screws interferes with the arms. For being a toothpick frame the arms seem stiff and comparable to a Floss v2 in terms of amount of flex across the arms. The edges on the carbon fiber is clean but sharp, so I ran a file over it to smoothen it out a bit. I like how they have slots on the bottom plate for you to use a battery strap. But I did not use it because I wanted to save some weight and went with a rubber band instead (Warning, the battery will eject if you crash when using a rubber band).

During the maiden flight the HQ S4 3 blade props did not well. I was a bit surprised because this setup was similar to the Floss v1 that I built in the past. I notice most people are using bi-blade props with 5” toothpick frames so I thought it would not hurt to give it a try. Of all the props I tried so far, the Master Airscrew 5X.4.5 Bi-Blade seems to perform the best. But I need to do more testing before I can really be sure.

After reviewing my DVR flight footage, I noticed the throttle percentage is way too low. The quad will start hovering around 13% throttle and usually do not go more that 30%. So, it seems to me I that can benefit more with a lower KV motor.

So, stay tuned to see what happens when I switch to a different motor.

March 06, 2020 - New Motors
I just finished installing the DYS BE1806 2300KV Motors! And with a doubt the 1806 2300kv motor is a better choice for me. With a 2 blade props I can get 6 – 7 minutes of flight time (that time is based on my flying style). But I am not really a fan of 2 blade props because it does not see to have the same bit at a 3 blade. So, I decided to try the HQ S4 Tri-Blade props again with these new motors and OMG…. This setup is now worth keeping.

I am currently using stock Betaflight 4.0.6 PIDs and Rates and I could always fine tune it later. Even with the stock setup it flew pretty well.

Photos

Part List

Frame

BETAFPV X-Knight Carbon Fiber Frame Kit (3 builds)
Getfpv.com
$18.99

Flight Controller

BetaFPV Toothpick F4 V2 2-4S AIO Whoop Flight Controller w/ 20A 4in1 ESC - XT30 (24 builds)
Racedayquads.com
$41.99

Motors

4 x DYS BX1806 2300KV Race Edition Motors CW CCW (2 builds)
Cyclonefpv.com
$39.96

Propellers

HQProp Ethix S4 Lemon Lime Props (Set of 4)
Getfpv.com
$3.26

FPV Camera

Caddx Tarsier V2 4K Dual Lens FPV Camera w/ WiFi (46 builds)
Getfpv.com
$88.99

FPV Transmitter

TBS Unify Pro Nano 5G8 (93 builds)
Team-blacksheep.com
$19.95

Antenna

Team BlackSheep TBS Crossfire Immortal T Antenna - Heli-Nation (27 builds)
Heli-nation.com
$4.99

Receiver

TBS Crossfire Nano Rx (703 builds)
Getfpv.com
$29.95

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

3D Printed

BETAFPV X-Knight 4K Canopy Adapter Caddx Tarsier by wrong17
Thingiverse.com
See Site

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
$27.95

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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