Build a Mini Racing Quadcopter for £50

Flying things are cool, especially when they’re fast! Follow along as I build this 250 sized mini quad.

I wanted to budget around £50 for the build, excluding transmitter, battery & charger.

These are the parts I bought;

- 1806 2300KV Brushless Motor x4pcs – £18.88

- HobbySky 20A Simonk Brushless ESC x 4pcs – £14.49

- Generic H Quad Frame 250mm Fibreglass – £10.46

- CC3D Openpilot Flight Controller with Black Case – £9.98

- 6030 6*3 2-Blade CW CCW Nylon Propeller x4 – £2.62

Total – £56.43

I use the flysky fs-t6 transmitter which is great and really cheap at just over £30/$45. You can use a cheap lipo charger from eBay but a proper balance charger is so much better.

Optional for FPV video

- 7″ Inch TFT LCD Mirror Monitor – £22.90

- TS5828 5.8Ghz 600mW AV Wireless Transmitter – £17.36

- RC832 5.8G AV Receiver 32CH – £16.10800TVL PCB Board Camera – £7.98

Including FPV – (£64.34) £120.77

Grab your frame parts and get assembling, there are a load off slightly different designs out there so I recommend following the instructions that came with your frame. If you didn’t get any like me then have a good guess. You’ll figure it out eventually!

This steps pretty easy, just grab your motors and screw them to your frame with those tiny bolts that came with your motor. Drop a little bit of thread-lock onto the bolts if your worried about them vibrating out.

Okay so a quadcopter has 4 motors, which means we need 4 electronic speed controllers (ESCs) to power the motors, one for each motor. I’m using a power distribution board which splits the power from the battery to each ESC. You can just solder the wires together but using a board makes it much easier and usually more reliable. Make sure you get the polarity right or you’ll be sure to release the magic smoke. You’ll also want to solder some wires to connect to your battery. I’m using an XT-60 connector. I secured the board to the bottom with double sided foam tape. That stuffs really useful! Use zip ties to strap the ESCs to the arms and tidy the power wires.

So we have the ESCs and the motors but there not connected together yet. Lets change that. Usually I use bullet connectors but as this is a racing quad we want it to be as light as possible so I chose to just solder the wires together. Your going to want to use heat-shrink on all the connections to prevent short circuits but don’t shrink it yet as you might need to swap some connections later on. Just solder each of the 3 wires from the ESC to a motor wire. Give the freshly soldered connection a tug to make sure its secure. Then slide the heat-shrink over the connection but remember to not shrink it yet.

Theres loads of multi-rotor flight controllers out there. I’ve read some good things about the CC3D so I used it for this build. I think its great! Really simple to setup and fly’s really well. I mounted it with some more of the foam tape which works well, make sure the its pointing forward. Follow the wiring diagram to connect the ESCs to the CC3D, we’ll connect the receiver in the next step.

You’ll want to download the open pilot software from https://wiki.openpilot.org/display/WIKI/OpenPilot... which will enable you to configure the flight controller properly. Please note that the latest version that supports the CC3D board is 15.02.02 just scroll down a bit on the download page to find this version. Once you have it installed open it up and you’ll be welcomed with the main menu. See that big green button? Press that to setup your quad. Read the message about removing the props and make sure you do it. Its not worth shredding your hands or worse for the 2 mins it takes to remove them. Okay safety over, click next.

1. Now were going to update the firmware on the CC3D, check the erase all settings box and then upgrade. Make sure you don’t unplug the board.
2. Next connect to the board to continue the setup by clicking next.
3. Select the type of signal your receiver uses, most use PWM so if your not sure thats your best bet.
4. Continue and select multi rotor for the vehicle type.
5. Then choose “X” configuration.
6. Next select your ESC type, again if unsure leave the default selected.
7. It will now show you the options you selected. Make sure they look okay and continue.
8. Now were going to wire in the receiver to the CC3D, the diagram will help you here. Use the supplied cable to connect the receiver to the left side of the CC3D.
9. Now open pilot will calibrate the sensors for us. To help it do this place your quad on a level surface so its completely flat and click calculate. When done click next.
10. The ESCs need to be calibrated to ensure they all operate in sync with with the flight controller. Follow the instructions on the screen and continue.
11. Now we can spin up the motors and ensure they spin the correct way. Quadcopters have 2 motors that spin clockwise and 2 that spin anti-clockwise. We need to make sure that each motor spins the correct way. Follow the instructions to ensure the motors are spinning correctly. Remember we didn’t shrink that heat-shrink? Well if the motor is spinning the wrong way you will need to swap 2 wires on the motor. Make sure the battery is removed and desolder any 2 wires and swap them, this will reverse the motor. Next!
12. Select QAV250 for the initial tuning option. Then continue to save the configuration. Yay, were nearly done just need to setup the transmitter.
13. Turn on your transmitter, click the green button and move all the sticks and switches on your transmitter.
14. You can now select what flight modes you want, but can leave this as default if your not quite sure.
15. Finally select how you want to arm the quad, I use yaw left.

WE’RE DONE!
Disconnect the quad and now you can attach you props and plug in your battery and go flying. Enjoy your quad.

If you want some FPV action continue to the next step and leave the props off. If your leaving us here good luck and thanks for following along!

Attach the board camera with zip ties so in the event of a crash it will have some room to move a little and hopefully won’t break. Solder power connectors from the power board on the bottom and attach the video transmitter to the top with a zip tie. Connect video signal from the camera and power from the board to the camera and transmitter. Finally tidy the cables so they aren’t in the way of the props.