When building a quadcopter, deciding which motors and propellers to buy is tricky, but a very important decision. There is a lot of math and science that goes into understanding how the motors and propellers effect how a quadcopter flies or if it flies.
As a novice, it is very easy to be overwhelmed by all of it. The correct motor/prop combination needs to be chosen by considering the size and weight of the quadcopter, the length of flying time and the power and agility that are desired. Also, the battery and ECSs must be chosen to effectively drive the motor/prop combination. Continue reading to find out how to decide the combination that is best for you…
How to Decide?
The way I see it, there are two different ways to go about making this important decision.
- Research what other experienced pilots use and buy the same or similar equipment. Personally, I prefer this approach because it doesn’t require an understanding of the physics involved and I know the solution is proven.
- Understand all the science and purchase the motors, props, battery and ESCs based on that knowledge. This approach will take more time, money and could be frustrating if the parts don’t work according to spec.
Now here’s more on each approach..
Who are some great pilots and what are they using?
I am interested in First Person Video flying (FPV) and two of the best FPV pilots are juz who flies quadcopters and David Windestål who mostly flies trciopters. For over all amazing flying skills, Warthox is unmatched. These guys publish the equipment they are using either with their videos, on their websites or on various forums. Hey, if it works for them, it is plenty good for a novice like me.
Check out this amazing video by Warthox:
Towards the end of the video he shows that he is using:
ESCs – HobbyWing 10 Amp
Battery – 3S1500 20C
Frame – Flyduino frame
This is just one example, but I encourage you to watch these great pilot’s videos, go to their websites or various forums they post in to find out what equipment they use. FPV rigs carrying cameras will likely require bigger motors and props. For FPV, a great place to find tricopter building information is David’s site at rcexplorer.se or see what juz is doing over at the openpilot forum. All of these guys share their configurations openly and I sure do appreciate being able to learn from them.
Also, I have started a list of pilots and some of the configurations they fly. You can also submit your own proven configurations to be added to the list.
On the other hand, if you want to build a quadcopter from the ground up and decide on a configuration of components from scratch, here are a few places to start…
Understanding the Science
If you prefer to understand the science, I can suggest a few resources that may help. Realize that you may spend a lot of money on various part combinations to test your theories.
To learn the the basics of watts, amps, volts, motors, props, etc. I suggest reading through an excellent series of articles called “Understanding Electric Power Systems” by Jim Bourke. There are five articles in the series:
Quadcopter Motor and Prop Calculators
After getting a good understanding of electrical power systems, there are some great calculators on the web that allow you to model combinations of components to see if they will work together and how they will perform. Two good calculators are the “Estimate Electric Motor & Prop Combo” calculator found at rchomepage.com and xcopterCalc that is designed specifically for multicopters.
So, good luck on choosing the correct combination of motors and propellers. Do it the easy way or the hard way. I think it is easier and better to go with a proven combination that other pilots are using.