I heard that a lot of problems occur due to one or more motors spinning the wrong direction. What process should I take to ensure that all my motors are spinning the correct direction if I'm using Betaflight?
In Betaflight you can have your motors spinning either props out or props in. The default is props in (towards the body of the quad from the front and back). Be aware other flight control software such as FlightOne and Kiss have different defaults.
If you are running props out, make sure you flip the switch on the Betaflight configuration tab to adjust that, otherwise your first flight will be VERY short and very fast!
Note that this switch does not change the actual direction of the motors! It's just a way for you to tell betaflight which way they're actually spinning. To check that the displayed and actual directions match, do the following:
In Betaflight go to the motors tab, read the warnings, then plug in your battery and click the enable motors switch. Run up the motors one at a time from their slider and ensure they match the direction and position of the charts above.
If you don't have access to a computer, alternatively you can simply arm your quad without props on and check the direction that way. Make sure you don't raise the throttle though, or airmode might kick in and you'll have the motors wind up due to I term buildup from the PID controller. This isn't an issue from the motors tab, so choose that option preferentially if you can.
In both cases, you can either brush the flat of your finger lightly against the motor or put a piece of tape on the shaft before you run them up. Make note of any motors that are out of order or not spinning the direction you want.
There are two ways you can fix the motor direction. One relies on a soldering iron or bullet connectors, the second relies on using software to change the direction.
Method One - Physically Change the Wires.
On the motors that are not spinning the correct direction simply desolder and switch pads on the ESC of any two of the motor wires. This will swap the direction of that motor.
Method Two - Betaflight and BLHeliSuite
If you already have your computer up, you can use BLHeliSuite to change the motor direction. The first thing you need to do is identify what type of ESCs you have. If you have BLHeli_S ESCs you'll need the Suite labeled 16.XX from the BLHeli Google Share. If you're using BLHeli 32 ESCs, download the 32.XX Suite.
Once you've downloaded the appropriate suite, make sure the Betaflight configurator is disconnected from your flight controller, extract the contents of the zip file, and run the executable.
Repeat for any other ESCs needed and then click "Disconnect".
Once you've finished, go back and repeat the check process once again until everything is correct! That's all there is to it!
Put the propellers on correct
Finally, when you go flying, ensure that you put your propellers on according to the direction of your motors. Most flip outs are caused not by the motor spinning in the wrong direction, but by a right propeller being mistakenly put on a left motor or vice-versa!
If you're new to the hobby, it might help to carry a sheet of paper with you with the directions printed on it, or color-code your motors and props with a marker so you can't go wrong.
First, remove props.
Then, establish if you are set to be running props in or props out.
Plug in a LiPo whilst the quad is still connected to the computer.
Go to the motors tab and read the safety information. Then individually spin up each motor to make sure it is spinning in the expected direction. You can do this by feeling the rotation or sticking tape on the shaft and seeing which way it turns.
If you don’t get the expected result, use BLHeli to change your motor direction.
Sometimes the fast RPM of the motors makes it hard to tell what direction they are spinning. You can take a piece of masking tape and place it on the motor shaft to make it easier to see. Then you can take the necessary steps to get the motors rotating correctly. Most of the quadcopters you encounter will have the motors with 'props in' which means the front props will rotate with the leading edge (think of a disc) turning to the center line of the quad and the rear props will have the trailing edge spinning to the center line.