Folding propellers for Rocket Drones

Folding propellers for rocket drones

What's a Rocket Drone you ask? Think of a Rocket Glider but instead of wings it has drone pods and can recover like a drone.

One of the first successful ones I've seen is a [Mars Lander](https://www.rocketryforum.com/threads/mars-lander-rocket-quadcopter-project.151995/) being developed by George Gassaway based off a model offered by [Mech-G](https://www.thingiverse.com/thing:2670642).

George's project has the motors facing down and to reduce the influence of the props on the thrust phase, a folding prop concept was proposed but because there were no commercial 'reversed' folding blades some of us started looking into 3D printing them, and that pretty much brings us to this listing.
V4
The V4 batch of blades was inspired by [Mech-G's design](https://www.rocketryforum.com/threads/mars-lander-rocket-quadcopter-project.151995/page-2#post-1895110) and I'm in the process of testing them, so use them with caution. I will post my results l