How to build a drone
I was first captivated by the power of drones after seeing a beautiful aerial video. I remember the exact video, and the images of surfers riding waves against a Hawaiian sunset were stunning. Over the following months, I saw came across more and more examples of the incredible power of drones. The idea that an average person could have the capability to capture and subsequently unlock such an enchanting scene stayed with me. I began to wonder just how difficult it would be to build my own.
Initial Research
After some searching, I discovered RCGroups.com, an expansive discussion forum with dozens of posts everyday dedicated to “multirotor” remote controlled aircraft alone. Multirotors, specifically the four rotor variety called a “quadcopter”, I quickly learned to be the platform of choice for drone enthusiasts. The combination of stability and maneuverability made quadcopters the ideal aerial vehicle for shooting video, or accomplishing a variety of other tasks, like surveying a field or delivering beer.
The comprehensive discussions on RCGroups.com about what drones to start with and how to learn to fly were incredibly helpful, as were the numerous YouTube videos and how-tos I found among the discussions. The general consensus is to learn the basics of flying first, before investing in an expensive aerial videography rig. Crashes, especially while learning, are common.
Build Your Own Adventure
There are a few good options for learning the ropes of your drone. Many start with a small microcopter, something like the Hubsan x4, which fits in your hand and costs about $40 - $50. Good options for something a bit larger and more powerful include the AR.Drone 2.0 ($249), and the most popular consumer drone, the DJI Phantom series, which can run anywhere between $500 and $1,500 depending on how it is equipped.
For myself, I was drawn to the option of building one. There are a few advantages: a more complete understanding of how a drone works and how best to operate it, the ability to upgrade and modify your drone as your gain experience (such as adding more powerful motors, or a different camera), and the capability to repair and replace most major components in case of a failure or crash. I also wanted the option of picking particular components. For example, I wanted to learn to fly using the same flight controller (onboard software that controls the flight of the drone) on my practice drone as I would be using for taking video once I learned to fly. In this case, that meant the DJI Naza flight controller, known for providing steady and stable flight perfect for shooting video.
While I wasn’t ready to build a quadcopter from scratch, I quickly found recommendations for build kits that included all the basics, while providing build flexibility and the option to pick your own flight controller.
(Almost) Ready to Fly
For my build, I picked the DJI Flame Wheel F450 frame. The DJI Flame Wheel series is known for being extremely durable, withstanding numerous crashes - an excellent quality in a first quad. The DJI Flame Wheel also comes in a 330 and 550 size (the numbers represent the diagonal measure of the quadcopter in milimeters). The 330 is a little small for most camera and limited in what it can carry, while the F550 is actually a hexacopter, with six rotors instead of the typical four. The complexity and costs of the F550 put me off a bit, and I knew I wanted to experiment with camera setups down the road. The F450 seemed like just the right size.
You can equip the frame with whatever components you want, but if you still don’t know what ESCs are or the kv rating on a motor is, you, like me, might want to consider an “almost ready to fly” (ARF) kit. The ARF kits contain a lot of the basic components for the frame, all matched and guaranteed to work with each other. I knew I’d be learning enough without starting completely from scratch, so this seemed like the perfect option. I quickly learned that even the ARF kits are no simple assembly, but were also very rewarding to put together..
Picking the Right Co-pilots
The DJI F450 ARF Kit contained the quadcopter frame, ESCs (for controller power to the motors), motors, propellers, and some other accessories. Major items that remained were the flight controller, the battery, battery charger, and the controller system (transmitter and receiver). I already knew I wanted to use a DJI Naza flight controller, and there appeared to be no major differences between the cheapest (“Naza-M Lite”) and more expensive variants, so I ordered a Lite along with the optional GPS module, which offered more controlled flight.
Several of the build tutorials I saw used a Spektrum DX6i transmitter (controller) and the corresponding receiver (for receiving the controller signal on the drone), the AR6210. While I subsequently learned this fine transmitter was actually a bit overkill (A Turnigy 9x would have been just fine for about 1/3rd the price), it is an excellent transmitter with great range.
The batteries for a modern quadcopter aren’t your everyday Duracells. They’re high performance, high capacity, potentially dangerous Lithium-Polymer batteries that require a specific, programmable balance charger. Most people flying F450’s seemed to be running 3 cell (“3S”) or 4 cell (“4S”) batteries in the range of 2000 - 4000 mAh. The milliamp hour (mAh) is a measure of battery capacity. Larger mAh measures indicate more power but also larger and heavier batteries - and larger price tags. Seemingly, the optimal battery type and capacity depends on the weight of your quadcopter, what other electronics you’re running on it, what type of motors you’re using, and what size propellers. Looking at some similar setups, a 3S 3000 mAh seemed like a comfortable middle-ground option, so I placed my order for a Turnigy branded one in that specification.
It seemed prudent to invest in a high quality charger, as they last and using a substandard one can quickly damage an investment you’ve made in batteries. I went with the IMAX B6-AC, based on some forum recommendations and tutorials on YouTube.
Learning to Fly Solder
The most daunting piece of building my own drone was the soldering required to link up the power leads on the F450 frame. I’d never worked with a soldering iron before, but watching some tutorials on YouTube, it seemed easy enough to learn.
I didn’t want to learn on my drone though, so I found a few different practice kits on Amazon useful for learning and practicing soldering. Most of what I’d read recommended at least a 40 watt, adjustable soldering iron. Without too much investigation, I picked one such well reviewed option on Amazon to accompany my practice kit, along with a spool of 60/40 solder.
Working through the practice kit was extremely helpful, especially with a few YouTube how-to videos to go along with my hands-on experience.
Drone Accessories
In addition to the soldering equipment, a number of people seemed to cover their soldering work with hot glue from a glue gun to insulate the solder points and prevent electrical short circuits (when current from one solder point is connected to another in the wrong way, which can result in some sort of disaster I didn’t want to experience directly). Hopefully you, upstanding undertaker of fine crafts projects, already have a hot glue gun. I did not, so the cheapest one I could find quickly appeared in my Amazon cart.
In the best videos I saw on the assembly, the builder also wrapped the wires with nylon sleeves. The end result was quite professional looking, and now fancying myself and expert (you know, being able to solder and all), I endeavored to do the same and found some cheap wire sleeves and some heat shrink tubing along with a heat gun to shrink them.
Finally, zip ties were used in a number of areas for most of the builds I saw, most notably to secure the ESCs to the bottom of the frame arms, so with some cheap zip ties in tow, I completed my order.
Assemble the Drones
Throughout my build, I followed video’s of other F450 builds closely. After preparing the wires with some wire sleeves, the first major step was to solder the ESCs leads onto the frame control board. At this point, I realize the battery leads that came with the DJI F450 kit didn’t actually have connectors on the end to connect with my battery. Most people appeared to solder together their own connectors, but I took a shortcut and ordered some pre-made ones off eBay for a few dollars, as well as the required connectors to connect my battery to my charger. With the connectors all working, I soldered my new battery leads onto the control board and topped all the soldering off with some hot glue.
Next up was screwing on the motors into the frame arms. At this point, I realized I had forgotten to purchase a hex screwdriver (you’ll need a 2mm) for the assembly, or threadlocker to lock the screws in place. Both I was able to find at HomeDepot, after explaining to an employee what threadlocker was, along with a small magnet to magnetize the screwdriver.
Back in business, I screwed on the motors with a dab of threadlocker, and threaded the wires in through the arm. Next was to screw the arms onto the control board and hook up the ESCs and wires - all fairly straightforward. Next was connecting the Naza flight controller to the ESCs and receiver (the wiring order to the Spektrum receiver is different than the Futaba receiver shown, but the lettering / naming is the same, so just match the same pairings), and attaching it in the center of the control board with the included double sided tape, making sure to point it in the right direction (arrow pointing forward). After this, I was ready to wire up the Spektrum receiver and secure it and its satellite with zip-ties, along with the Naza LED unit. Finally, I was ready to screw on the top of the frame, assemble the Naza GPS module pole (quick trip to CVS for some super glue for to connect the pole pieces), and attach it to the top of the frame with double sized tape (it sticks). Care needs to be taken to point the GPS in the proper direction (arrow facing forward).
The only thing missing from my drone was the propellers and some power. It is advisable to leave the propellers off until everything has been tested with the motors on and running. To do that, I’d need to be able to talk to my drone and charge my battery. Charging a LiPo battery is a little more involved than the average charge, but again YouTube walked me through the process.
If You Love Something, Bind It To Your Transmitter
Not wanting my newly assembled drone to fly away on its own, I’d need to connect it to my Spektrum transmitter. This was accomplished within a few seconds, using the supplied bind plug.
I wasn’t done though - one must next program the Naza flight controller to the right settings for the transmitter. This part was probably the most trying, requiring a lot of trial and error. There are a few videos online of how to setup the Naza with the Spektrum DX6i I had, but they all were slightly different. A good basic introduction is here, and there are a number of videos on how to get the mix settings right for the different flight modes. The important thing is you can see everything as it happens in the DJI software, so it just takes some tweaking to get all the values correctly. The values in the various videos were close, but not exactly correct for my build.
Initially the software wasn’t picking up my transmitter inputs at all, but I had some of the basic configuration settings incorrect. I’m not sure exactly what was wrong, but some experimentation eventually sorted it out.
With everything looking good in the Naza software, I fired up the motors using the proper stick combination and my drone came to life.
As The Propeller Turns
With everything running well, I was ready to (turn off my drone and) attach the propellers. Two things must be correct or certain doom awaits your drone. First, the motors need to be turning the correct way, and not all of them rotate in the same direction. When I first tested mine, using the paper method, I found that all of mine were turning in the same direction because I had wired them in identical ways.
A quick swap on any two motor connectors on the two ESCs switched the rotation to the correct direction. The propellers need to be matched with the right motors. Two of the propellers are designed to spin one way, the other two the other way. Examining the propellers and the rotation of the motors was enough to determine the right setup.
Additionally, the DJI kit comes with a set of 8” rotors and 10” rotors. While there seemed no consensus on which were better, I detected a slight preference among the crowd for the 10” on a 3S battery (and 8” on a 4S), so I went with the 10”.
Flight Check
I was now ready to take my quadcopter outside to my flight location. I was disappointed to find that I couldn’t get my flight controller into GPS calibration mode, despite following some video instructions. After some searching, it seems the trick is to start in one mode and end in the other mode, while switching back and forth about 7 times.
I calibrated my GPS and checked the LED codes for my different modes of flight. Here I discovered that I wasn’t able to get into GPS mode properly, so I returned to my Naza software to adjust the values slightly higher on one of my mode settings which now seemed to hit the right value.
To Infinity and a Stable Hover
Everything looking like a go, I was ready to take off. My first flight wasn’t the most exciting, but it ended without a crash. This I regarded as a major accomplishment. Now all that was required was a bunch of practice.
Build Details
DJI F450 ARF Kit
- DJI F450 Frame
- DJI ESCs
- DJI Motors
- DJI Propellors
Naza Lite Flight Controller with GPS Module
Spektrum AR6210 Receiver
Spektrum DX6i Transmitter
Turnigy 3S 3000mAh Battery
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