Microsoft never ceases to amaze me.

Rotor spin does need to have something providing a balancing force if you don’t want to spin. That’s why helicopters have tail rotors and quads have two CW props and two CCW props. That said, before quads became the standard design there was a lot of experimenting with tricopters, two motors that have opposing spin directions at the front and the third motor mounted on a “tail boom” that could be rotated by a servo to tilt the propeller to create the forces to not rotate and keep a heading or to turn the craft. So not all “drone” designs have an even number of props.

You do know that 3d printed guns are not 100% plastic, large chunks of them are just normal metal gun parts. I’m also wondering what you think bullets are made of?

Please don’t repeat stupid shit like saying 3d printed guns go past metal detectors. It will hurt the 3d printing community.