This 3D printed jig will let you make propellers from craft sticks. You can attach these to thin dowels to make hand-powered helicopters, or put nails through them and use a bead to make pinwheels. If you're clever, you could make a whole windmill to power a small machine with them.

Stuff you will need

Propeller Jig ( http://www.thingiverse.com/thing:1930822 )
A craft stick
Craft sticks come in two standard sizes. The jig works equally well with both.The larger ones make better propellers.
- Popsicle stick sized ( 113 x 9 x 1.5 mm)
- Tongue depressor sized ( 148 x 17 x 1.5 mm)
Pot, water, fire
6 penny finishing nail ( 2.6 x 63.8 mm)
Helicopter:
- Small nail ( 2-3 cm)
- Wood glue
- 150 x 5 mm dowel
Pinwheel
- Small nail (2-3 cm)
- Small bead ( 3-5 mm)
- 150 x 10 mm dowel

Step 1: Mark Center of Craft Stick

Mark the center of your craft stick. Fit the stick into the slot at the bottom of the jig, then push a 6 penny ( 2.6 x 163 mm) finishing nail point-first through the hole in the top of the jig. Press firmly to leave a visible mark in the wood.

Step 2: Boil Craft Stick for Thirty Minues

Boil your craft stick for thirty minutes to soften it. You may also be able to soak it in water overnight. Make sure it is completely submerged. I threaded it through the tines of a fork here to keep it down. Be careful handling the hot water!

Step 3: Make the Propeller

Thread the stick into the jig and leave it overnight to make your propeller. The stick cools rapidly outside of the water, but it will remain soft and pliable for many minutes.

Step 4: Craft Stick Helicopter: Nail the Propeller to the Top of a Dowel

Drive a small nail through the center mark of the propeller. Put a little wood glue or Elmers white glue on the top of the dowel. Carefully align the nail with the center of the top of your dowel, then pound it in straight and tight.

Spin the dowel between your palms to launch the helicopter.