Building Your First FPV Drone Racer

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Drone racing has steadily gained in popularity over the years, graduating from a niche in the consumer market to having its very own ESPN-televised league. For beginners and many intermediates, participation usually involves a pre-assembled setup that comes Ready-to-Fly (RTF) out of the box. However, as many pilots will tell you, the best drones are built, not bought, which means at some point you’re going to have to get your hands dirty. With that DIY-attitude in mind, we've put together a high-level look at how to build your very own drone racer.

Now, since this is a high-level look, we’ll try to stay clear of the more technical aspects and modifications and focus instead on the parts you’ll need and provide a general building overview. Some instructions might sound beyond your reach (hello, soldering), but trust us, they’re not. The great thing about building your own racer is that with a little patience and research, anyone can do it, regardless of technical savvy or know-how.

To start, let’s first discuss the components. Regardless of cost, class, or skill level, FPV racers all have the same core set of parts.

Air Frame

This is the body of your drone. It's where all your components are connected and housed. The standard for FPV racing is an X-styled, carbon-fiber frame, in the 250-size class. A great example of this, and the frame we’ll be using as our example going forward, is the QAV-X FPV Racing Quad, from Lumenier.


Lumenier QAV-X CHARPU FPV Racing Quad

Propellers

The four rotating blades that help propel your quad. Props come in different styles, materials, blade counts, and with different attributes. You'll have to experiment to discover which props works best for you, but a good place to start is with a 5-inch, 3-blade propeller. Brands like Gemfan offer a wide selection of props and are a good place to start when shopping for blades.


Gemfan Glass Fiber Nylon 3-Blade Bullnose Propellers

Flight Controller

This is the brains of your racer. All signals pass through this board and are converted into action. There are plenty of great choices available. We’d recommend looking at brands like Lumenier or Flyduino, both of which offer controllers used in championship racers.


Flyduino 32-Bit Kiss Flight Controller V1.03

Power Distribution Board (PDB)

This board regulates how power is distributed throughout your drone. In most builds, the PDB connects directly to the flight battery, and distributes power to the other components. You can purchase a PDB of your choice, or, if you go with QAV-X, one will included with the frame.


FlySight Simple Power Distribution Board

Electronic Speed Controller (ESC)

The ESC controls the speed of each motor. ESCs can either be installed individually (1 ESC per arm), or you can use a 4-in-1 device, which requires less soldering and can produce a cleaner-looking installation. The tradeoffs with the 4-in-1 are limited placement options, and if you smoke your 4-in-1 ESC, the entire board must be replaced; with individual ESCs, you must replace only the bad one.


BLADE 20A ESC for Vortex Pro Quadcopter

Motor

The motor assembly is what’s responsible for spinning your props and providing enough thrust to fly. When building a racing drone, you will need four brushless out-runner motors. Plenty of good options are available, including the Lumenier MX2206-9, which we’ll use for this installation. We would also recommend looking at T-Motor. Their selection of motors is very popular among FPV racers, and for good reason: T-Motor motors consistently deliver excellent thrust, don’t overheat easily, and feature a lightweight design.


T-Motor F40 II Motor for Racing Drones

Battery

The flight battery supplies the power to your quad. It’s always going to be a Lithium-ion Polymer (LiPo) battery and, odds are, you’ll probably be using either a 3S or 4S configuration. For our installation, we’ll be using a Tattu 4S 1300mAh LiPo Battery with an adequate discharge rate of 75C.


Tattu 75C LiPo Battery Pack

Radio Transmitter/Receiver (TX/RX)

The radio-control system for your drone is made up of a handheld transmitter and a receiver board, which we’ll install on the drone itself. At the minimum, your radio system must have at least four channels to properly control your quad, but you really want something with at least two auxiliary channels for performing additional functions or triggering certain flight modes. For our installation, we’re using the Taranis X9D Plus with X8R Receiver, both from FrSky.


FrSky Taranis X9D Plus Mode-2 Transmitter with X8R Receiver

Camera System

Your First-Person-View () setup includes your FPV camera and video transmitter (TX). This is a crucial component, because quality video and video transmission are what make FPV racing possible. One of the best producers of FPV equipment is RunCam. We’ll be using its Swift Mini in our build.


RunCam Swift Mini FPV Camera with 2.8mm Lens

FPV Goggles

Your FPV goggles (headset) receive video from the FPV TX, allowing you to see through the camera lens in real time. Goggles don’t require any assembly, so we won’t touch on them here, but when shopping for yours, keep in mind brands like Fat Shark and Walkera, both of which are industry leaders.


Fat Shark DominatorV3 WVGA FPV Headset

Your drone components can be purchased either as part of a kit or individual pieces. The advantage of purchasing a kit is that compatible pieces have already been pre-selected—you simply must put them together. If you are buying components separately, be sure to consider the whole picture before purchase: Are these props the right size for my frame? Is the battery compatible with the current draw? The answers to these questions are relatively easy to find, either on the manufacturer's website or in any of the countless online resources—just be sure to keep the entire build in mind, lest you end up buying the wrong part.

Now, in terms of tools, you will need a soldering iron and solder. You should also have wire cutters and, depending on your frame, a compatible hex key or screwdriver. If your frame doesn’t come with nylon standoffs or spacers and a LiPo (our does), you will need those as well. Other helpful tools, such as zip-ties, two-sided tape, heat shrink, and Loctite Threadlocker Blue can also be used to keep the installation neat and secure.

Once you have all your tools and components, it's time to start the build.

We'll begin by attaching the four motors to the air frame. When installing the motors, you want to make sure your counterclockwise (CCW) spinning motors are placed on the front right and back left arm, and the clockwise spinning (CW) motors are installed on the front left and back right arm. You also want to make sure the motor wires are pointing inward along the arm so that they can be easily connected to the ESC. To ensure the motors are secure, we recommend using Loctite on the mounting screws.

After the motors are installed, it's time to build your stack. If you're using a 4-in-1 ESC, the stack is your PDB, ESC, and flight controller. If you're using individual ESCs, your stack will be the PDB and flight controller. For this installation, we’ll be using individual ESCs, so our stack will be the PDB on the bottom and flight controller on top.

First, we need to create a standoff for the PDB to sit on. The standoff allows the PDB to sit above the frame so that it isn't making contact. This is a critical step, since most frames are made of carbon fiber, and carbon fiber conducts electricity; if your PDB touches the frame, it could short.

If you’re building with the QAV-X frame, use the four included plastic screws to create the standoff. To do so, simply screw the screws into the designated holes in the center of the frame. Before you place the PDB onto the standoff, install the LiPo battery strap so that the PDB will be sitting above it.

Now that the PDB is in place, it’s time to install the ESCs. First, we’ll need to solder the power (red and black) cables to the PDB. Remember red is positive, black is negative. You’ll notice that there is an additional wire left over: that’s your signal wire; we’ll solder it to the flight controller later. Once each ESC is soldered to the PDB, it’s time to solder them to the motors.

Soldering ESCs to the motor is slightly trickier, but nothing too complicated. Each motor has three cables that connect to the ESC. For the clockwise (CW) motors, the cable order is: Left Cable to Left Pad, Middle Cable to Middle Pad, and Right Cable to Right Pad. The counterclockwise (CCW) motors are soldered slightly differently. The Middle Cable still connects to the Middle Pad; however, the Right Cable connects to the Left Pad, and the Left Cable Connects to the Right Pad. Soldering in this order is critical, because it ensures the motors spin correctly.

Once you've completed your soldering, use zip-ties or some other type of binding to hold each ESC in place on top of the arm.

The next step is to solder the power pigtail to the PDB. This is our LiPo battery connector, which we will connect to the battery at the end.

Finally, now is a good time to solder the wires or connector we'll be using to power our camera and video transmitter (VTX).

Once your PDB soldering is done, you're ready to move on to the flight controller. Create another standoff on top of the PDB using the spacers that came with your frame (or that you purchased separately). Once the standoff is installed, mount your flight controller in place. Finally, solder your ESC signal wires to the flight controller and connect the receiver (RX) and you’re all set.

Now we're ready to install our camera setup. Depending on what frame and FPV system you use, this stage can vary. Different frames come with different housings or canopies (or none), so installation isn't universal. If you’re using the QAV-X frame, plates for building a camera housing are provided.

Once your housing is complete and your camera is secured, you can install the video transmitter and antenna. Connect the VTX to the PDB and secure the transmitter and antenna to the frame using zip-ties or some other binding.

Finally, you’re ready to install your props and secure your battery. Match the props to the corresponding motor and make sure they’re tight and spin freely. Now, strap the battery to the bottom of the quad using the LiPo strap we installed and plug it into the pigtail connector.

And that’s it!

You’ve just completed building your very first FPV drone racer. The final step is programming your flight controller, which is a breeze and can be done quickly and easily using your home computer and free software. After that, you’re ready to get out there and race!

5 Comments

Lumenier items are all discontinued on B&H?  

Great start but the article needs to be finished with a show of the finished drone and some shots of it flying.  How about putting together a kit package and offering it on your website?

This is literally the best intro to creating these I've ever seen! You've clearly outdone yourself. 

 

Would love it if you could complete it so that there are graphics for the remaining steps of soldering on camera, etc. 

This is SO interesting. I kept saying "WOW" to each and every discovery here. Considering I installed a video receiver and transmitter in my Phantom 2 (which worked) this seems to be a doddle. Building my own quadrocopter has crossed my mind more than oncerecently - and this kit seems a damned fine place to start and a great promt to get started. Expect to see some ordering traffic, guys. Thanks B&H - as always.