My last post detailed the most necessary components for building your own drone. However, a drone will not function without a frame, some type of control method, and a way to safely manage power from the battery. Lets start with the frame. When I built my first quad, I thought to myself, "how hard can it be to build my own frame." It only took me two days to design, get the parts, and build a frame for my quadcopter. At the end of it, I ran into two major problems. One was a secure way of mounting the motors, and the other was how to prevent the electronic components from touching the frame which was made out of sheet metal. The insulator problem was an easy fix; I just put a foam piece under the flight control board. The motor mount problem was harder to solve. I was able to drill holes in the aluminum bars that my frame consisted of, but I'm not a very good driller. Some screws didn't line up with holes on the motors, causing some motors to get loose during flight. Of course, I could have spent more time designing the frame better to withstand more impact, but in end, I had two pieces of sheet metal sandwiching four hollow aluminum bar all held together with globs of JB Weld. This was not a great design, because JB Weld can hold a lot of weight, but upon impact JB Weld, actually most glue/epoxy, will crack or shatter. That's exactly what happened when my drone crashed. After the crash, I decided to buy a frame from Hobbyking. The frame I bought was decently strong, and this time, it had the correct mounting holes, and it was made out of hard plastic. This frame was mostly successful, but when I crashed again, this frame cracked just like my first one. The Hobbyking purchased frame was very compact, measuring 250 x 250 mm, which is almost 10" x 10". I currently use the SK450 frame in my build. The benefits of this frame are that it is larger, meaning a lot more space to install parts, it uses a combination of fiberglass and plastic, so it isn't conductive, and it's modular. All the components making up the frame are completely removable and replaceable. This is the standout feature for me. If you crash and snap something, you can unscrew it and order the replacement part. Also, 3D printing websites have lots of support for this frame, meaning that you can 3D print accessories and add-ons that will fit this frame. The decision for building or buying your frame is up to you, depending on how experienced you are with D.I.Y projects. My recommendation for beginners would be to buy a frame, because they are affordable, and with the SK450 and many others, well designed. In my mind, the easiest part of putting together a drone is picking the transmitter and receiver. While there are many fancy transmitters with screens and other unnecessary functions, the one transmitter you should get is the Turnigy 5X 5CH. The reason being that this transmitter comes with a receiver bundled in, and suits the basic needs for flying a quad at a low price. When you go to buy this transmitter/receiver, you will notice that it comes in two variants: mode 1 and mode 2. These variants are two of the four types of RC transmitter layouts. To understand an RC transmitter, you have to know the basic controls. Throttle is the level of power given to the motors, the aileron is the banked turns left and right, the elevator is the forward and backwards movement, and the rudder controls to yaw of an aircraft (circular turning motion, spinning on an axis). Mode 1 has the throttle and aileron assigned to the right stick, and the elevator and rudder assigned to the right stick. Mode 2 is not the opposite, instead, switching the places of the elevator and the throttle. There are many tutorials on how to fly your drone, but I will write a separate post detailing it. The last and most forgotten part of a drone is the power distribution system. I actually didn't know you need this on my first quad. Most people would think that the battery just has ports to plug the ESCs into and flight controller into, but it's not as simple as you would think. Basically, you need something to evenly split the power from your battery to all of your ESCs, and don't worry about your flight control board, it gets its juice from the ESC plugged into the set of the first motor pins (that's how it works with the KK2.1 board). My first quad, after realizing I forgot about it, had a wire splitter that plugged into the ESCs from the battery. This was a decent solution, but the cables were a mess. I would recommend picking up one of the Hobbyking manufactured power distribution boards (not cable splitter). The reason for this is to make connecting all the cables much easier. One thing you have to keep in mind are the connectors for the battery and the ESCs. There are many battery connectors, but the most common is the XT60. This connector is usually yellow, and has two holes at the top. It tapers slightly when you get to the top, and you can't plug it in wrong. When you choose a battery, look on the product page and find what type of discharge plug it is. Make sure that this discharge plug matches the input plug for your power distribution board. There are some ESCs that require you to solder connectors on, but most ESCs use bullet connectors. This type of connector comes in many sizes, measured in millimeters. The ESC input on your power distribution board should match the power output connector on your ESCs. Another important and usually overlooked detail is the connectors on the motors. They are usually bullet connectors, like ESCs, but just make sure that your motor and ESC bullet connectors match in terms of size. All of the information regarding connectors can usually be found directly on the product page. If the wiring seems a little complicated at this point, don't worry, I will recap what I just said. From the motors, three wires come out. One is for positive power, one for negative power, and the other is for signal, or data carried to the flight controller board. These wires will plug into your ESC. From each ESC, there with be three wires coming out. One will be positive power, the other will be negative power, and the third will be one wire made up of positive power for the flight controller board, negative power for the flight control board, and signal for the flight control board. The positive and negative power bullet connector cables coming from each ESC will then plug into the aforementioned power distribution board. MAKE SURE YOU PLUG IN THE NEGATIVE WIRE INTO THE NEGATIVE SLOT, AND THE POSITIVE WIRE IN THE POSITIVE SLOT. If you don't, something will end up short circuiting, leading to a possible fire. Just for your info, male bullet connectors look like small bullets, and female bullet connectors are the holes in which the male connectors sit in. The third wire coming out of the ESC will not be a bullet connector, instead a flat cable consisting of three thin wires. Coming from the power distribution board will be a single XT60 or other connector that your will plug into your battery. Also, any positive power wire will be represented by a reddish color, any negative power wire will be brown or black, and any signal wire will usually be yellow, or any other color besides black/brown or red. Just remember that the previous process happens four times in the case of a quadcopter, one time for each motor. Because of this, there will be many wires. I suggest buying some cable or zip ties and/or adjustable Velcro straps. One very important tip is that even if your frame isn't conductive, it could include metal screws or brackets. Make sure components like your flight controller and power distribution board do not touch any sort of conductive material. I learned this the hard way when my power distribution board shorted out and destroyed one of my ESCs, my flight control board, and my battery. If you're wondering how to mount all your components, I will have a separate post where I show you how to actually build a drone. If you're reading this, you probably came from my YouTube channel. If not, subscribe to my channel, which focuses on tech reviews. I will also be posting camera footage from flights with my quadcopter, and possibly video tutorials on D.I.Y drones to furthermore make drones as easy as making microwave mac n' cheese.
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