3-Inch 3018 Propeller — AI-Designed, Resin-Printed, Flight-Tested

What is this?

A 3-inch, 3-blade propeller for small drones. I designed it with AI (Claude), tested it in a computer simulation, printed it in tough resin, and flew it on my own drone.

This is my own design, not a copy of a Gemfan file. I started from public photos and specs of a popular store-bought 3016 prop, then changed it: more pitch, a stronger blade root, and a hub made for printing.

What does "3018" mean?

Drone props are named with two numbers stuck together:

• 30 = 3.0 inches across, tip to tip (76.5 mm).

• 18 = 1.8 inches of pitch. Pitch is how far the prop would move forward in one full turn, like a screw going into wood.

More pitch pushes more air (more thrust and speed), but the motor works harder and uses more battery. The store-bought prop I started from is a 3016. This one has a little more pitch.

Will it fit my drone?

• Drone size: 3-inch drones (often called "toothpicks").

• Motor shaft: 1.5 mm (center hole).

• Screws: 2 x M2, holes 5.2 mm apart.

• Hub thickness: 5.5 mm.

Check your motor's screw holes before you print.

Which files do I need?

• CW spins clockwise, CCW spins counter-clockwise. A quadcopter needs 2 of each. The direction is engraved on top of the hub.

• STL works in every slicer. 3MF is the same shape in a smaller file. Pick either one.

• The version (P v2.4) is engraved underneath, so you can tell your prints apart.

How was it tested?

1. Computer wind tunnel. The simulation spins the prop in moving air and measures how hard it pushes. Result: about 380 g of thrust per prop at full throttle (45,800 rpm on a 4S battery).

2. Computer stress test. Spinning fast tries to pull the blades off. At 50,500 rpm, the weakest spot (where the blade meets the hub) only reaches about half of what PETG plastic can take. That is a 2x safety margin.

3. Real life. I printed it in Elegoo Tough resin (black) and flew it on my 3-inch drone (1404 3800KV motors). It hovered steady and felt like the store-bought props. I have not tested it at full throttle yet.

How do I print it?

• Use a resin printer. Parts of the blades are thinner than 0.5 mm, too thin for a normal filament (FDM) printer.

• Use tough resin. Basic clear resin was too brittle.

• Use light supports. They leave small marks (about 0.15 to 0.2 mm deep), so sand them lightly.

• Wash about 4 minutes in 99% IPA. Cure about 4 minutes, flipping halfway. Too much UV makes resin brittle.

• Test the fit of the screws and motor shaft before you fly. If the holes are tight, open them gently with a drill bit.

Stay safe

Props spin tens of thousands of times a minute, and a printed prop can break. Test somewhere safe, wear eye protection, and keep people away.

Can I use it?

• Personal use: yes, free. Print it, change it, share it. Just credit @offgridevices.

• Selling prints or using it in a product: ask me first. Message me on Printables or email [email protected].

License: CC BY-NC 4.0.

Watch and read more

• Video: Can AI Design a Drone Propeller That Actually Flies?

• Full story: Can AI Design a Drone Propeller You Can 3D Print and Fly?

• Frame I fly it on: 3-Inch Toothpick Drone Frame v8