Build vs Buy a Quadrotor?


Flying quadcopters is an expensive hobby. Flight controllers, motors, ESCs, batteries, and frames are not cheap. Regardless of whether you buy or build, it will probably cost over $300 to get started, with another $100 or more being spent every few months on upgrades and replacing broken or worn out parts. So, is it better to buy a kit with everything included in one package or assemble a quadcopter using parts built or purchased separately? For me, a DIY build is the best. Continue reading to find out why…

Kits

Kits are great for people who don’t have much time to spend understanding which components will work well together. The components in a kit are usually carefully matched and pre-soldered making them easier to build. They may also appear to be cheaper at first. Often, when you add up a similar configuration of parts purchased separately, the kit looks cheaper. The catch is that the kit contains parts that are only made by the manufacturer. So, when you go to buy replacement parts they are much more expensive than generic off the shelf parts. By the way, crashes inevitably happen and parts do fail.
Also, while the parts in a low end kits may be carefully matched, they may be poor quality parts or parts without many features. The flight control board is the most important part of a quadcopter. To get advanced features such as auto leveling, axis lock, altitude lock, position hold, or gps with way points, you will have to buy a very high end kit. From what I can tell, it is very expensive to buy a kit that has anything more than gyro stabilization. Read my post on gyros vs. accelerometers to understand the importance of this.
Though I have not purchased a quadcopter kit, the one that appears to be the most popular is the Gaui 330X-S.Less expensive quadcopters are listed at the goodluckbuy site. Good luck with those!

DIY

Conversely, when you build from a collection of parts that you purchase separately, it will take more time and perhaps even appear to cost more initially. However, it will be much cheaper to replace a part since you have lots of choices and are not forced to buy a part made by the kit manufacturer. Also, you can buy and configure any flight control board with whatever features you require. This gives you total flexibility of which features you need and want. It also allows you to change boards as your demands change. The following blog posts may help if you decide to do it yourself:

The Frame (Buy vs. Build)

Even if you decide to build your own quadcopter using parts purchased separately, you may want to get a frame kit. This way, you will know it is engineered correctly and you can still equip it with whatever parts you want.
Good frames can be purchased fairly cheaply, but the same problem arises when a part breaks and has to be replaced. You will likely have to buy a part made by the frame manufacturer and it may be expensive or unavailable. If you are going to buy a frame, I recommend this one from this one from HobbyKing or this one from HoverThings. I have not used either of these, but the first one is really cheap for carbon fiber and the second one is used by one of the best quadcopter pilots I have seen on the web. Unfortunately, if the frame is good and inexpensive, it make be on back order or it’s replacement parts may not be available. So, I really like to build my own.
Update 06/09/12 - Since I originally wrote this, frame prices have come down dramatically. The DJI F450 and theQ450 from HobbyKing are very low priced, durable frames that make great starter frames. Similar to the F450, HobbyKing also sells an upgraded version of the Q450 that has a built in PCB, so a wiring harness is not required. These frames are so cheap, it hardly makes since to try and build your own unless you just like to tinker. Also, I have since purchased the VC-450 from HoverThings. It is my favorite frame. However, it has recently been discontinued. It was replaced by an upgraded frame called the HT-450 which is a bit more expensive.

Building your own Frame

I have had a lot of fun building my own quadcopter frames. It is not that difficult and doesn’t require a lot of special tools or materials. However, it does take a lot of time and precise measurements. If you are pretty handy, have a drill or drill press and a hack saw or miter saw, building your own frame is the way to go. Here is my poston building a frame for under $10.
Frames can be made with lots of different materials. At a minimum, you will need some screws, center plates and arms.
Screws
Small screws can be found at rcsrewz.com or McMaster-Carr or on ebay.
Center Plates
Center plate material needs to be rigid, tough and light. I have been using plexiglass discs I bought off ebay, because it is really cheap and looks cool. G-10/FR-4 Epoxy or carbon fiber plates are lighter and probably stronger. But, they cost more and may have to be ordered from Asia to get the best price.
Arms
Quadcopter arms can be made of wood, aluminum, or carbon fiber. Again, strong, rigid and light are the characteristics to look for. I have been using wood. It is not very tough. Wooden arms will easily break in a crash. But, it is so cheap and easy to get that I don’t mind replacing arms when they break. I will probably experiment with aluminum and carbon fiber arms soon. Aluminum will bend in a crash, but it is also fairly cheap. Carbon fiber is probably the best alternative for everything, but it is also the most expensive and harder to find. To get carbon fiber cheap, it must be ordered from Asia. On the other hand, wood and aluminum are usually easily sourced locally.

Conclusion

Everybody has different budgetary and time constraints. For those with unlimited money and little time, kits are the way to go. But, for those of you, like me, who are on a tight budget and enjoy the fun of building stuff, I would suggest DIY all the way!