Hey guys, this is the final post of our homemade Arduino based drone which is very cheap to build. The full project cost less than $10. This project was very fun to make but also very frustrating when things were going wrong. I have done many testing, trial, and errors and also got it broken several times. After several weeks of working (around 3 – 4 weeks), this project is finally a success. In this post, I’ll show you guys step by step procedures to build this drone and what are the changes we made in our previous post to make this little fellow work. So, I have made this drone with wood sticks and 6 mm prototype breadboard.

The wooden sticks and breadboard will make the drone as light as we want it. You can also make this by designing the frame and cut it out of balsa wood which is also very light. Moreover, you can 3D print the frame also which is also very light and strong. I have not yet worked with 3D printed components but I intend to do in for my upcoming projects.

I am using gear mount for the motor and propeller. I was previously using a 14 cm propeller-like shown in images below. However, this propeller was causing some problems for our drone. During the test, one of my MOSFETs blows up due to excess current drawn by the motor. This was due to the propeller adding extra load on the motor. So, using this size propeller was not a good idea. So, I Changed the propeller to a smaller size which is 12 cm. This size of propeller is perfect for our drone and had not caused any problem until now.

We will now make the frame. Now the size of the drone is very important. Taking the size of the motor and gear mount into consideration, we cannot make the drone too small or too big. The length between two diagonal motors should be between 220 mm to 250 mm. I have made this drone 230 mm as after doing a lot of testing, I found this site to work best with all the components we are using.

We cut the prototype breadboard 5 cm x 5 cm. It should be perfectly squared. Cutting this board this size will give us a diagonal length of 7 cm.

Now if we see the gear mount, we can see that if putting the wood stick in the gear mount, we will have a 1.5 mm space between the motor center till the tip of the wood stick In the gear mount as shown below.

Performing the mass, if the diagonal length of the drone should be 23 cm and we subtract 7cm the breadboard to it (23 – 7) we are left with 16 cm. Therefore, from the breadboard to the center of the motor, we should have (16 / 2)) which gives up 8 cm. Now we have to subtract the small gap we had in the gear mount which was 1.5 cm. Therefore, 8 cm – 1.5 cm gives us 6.5 cm. Therefore, the length of each wood stick should be 6.5 cm and we cut it to this size.

Now I have tight the wood stick to the breadboard using insulated copper wires like this and I have to fix it in place using strong glue. It is very important to fix it in place and make sure that it is not moving. If it moves, it will create a vibration on the drone and make it very unstable. After fixing it with glue, wait for about 1 hour before doing any further work on it to make sure it is well fixed.

We then add the gear mount to the end of the wood stick and glue these also to fix it well. Before gluing it, make sure all the gear mount is well leveled, and none of them are tilt as this will make the drone unstable.

Now we place the propellers as follows: (A is clockwise and B is counterclockwise)
This configuration is very important. You can see that on all sides of the drone, adjacent motors are all spinning in the opposite direction of each other. This will cancel all the torque and therefore make it stable. This is the reason why you cannot use different size motors also as if a single motor torque is different, it will cause the drone to rotate and make it unstable. So always make sure you are using the same size, torque rated speed motors for every side.

 I am using 720 coreless motor for this project which is very small in size but very powerful. Now put the motors in place and make sure they are placed as shown below.

I am using two clockwise motors (red and blue wires) and two anticlockwise motors (white and black wires). If you have all motors having the same color wires, just reverse the polarities where we need anticlockwise.

This is done for the frame. Now check the next post below for the full control system.