Launch mini paper airplanes from your desk, without ever winding up your arm. Perfect for office shenanigans or other indoor fun!
By using common electrical components we can make our own electric paper airplane launcher!
You might even discover you have many of the parts required already laying around, especially if you have any old toys with small DC motors.

Check out the launcher in action:

^{Pretty neat, right?}

Enough talk, let's launch some airplanes!

Step 1: Tools + Materials

tools

wire strippers
soldering iron
rotary tool (or hacksaw)
hot glue gun
hobby knife

materials

2x DC motors (3V)
2x rubber grommets
SPST switch (or any other switch)
copper wire
scrap plastic
small hobby box
2x AAA batteries (or other 3V power)

Step 2: Wiring Diagram

Each DC motor is rated at 3V and each AAA battery is rated for 1.5V, so we'll need 2 AAA batteries and our motors to be wired in parallel.

The neat thing about these toy DC motors is that if you reverse the polarity they spin the other direction. Using this concept we can wire each motor up inversely to each other and create a opposing rotations, allowing a pinch-point to be formed by the rotors when placed next to each other. Then, by attaching rubber grommets to the rotor heads, we can use that pinch-point as a method to fling our paper airplane.

A switch was added to allow the motors to be user controlled.
Use care when wiring and don't short circuit your motors (like I did), or your batteries (which I also did).

Step 3: Make Openings in Hobby Box

Openings will need to be made for each rotor head, with allowance for the grommets, and for the switch and cables. I cut a large opening in one side of my box, exposing the entire front portion of the motor including the heads. Then, a large bore hole was drilled into the top for the switch and a smaller hole on the other end for the battery cables.
Your hobby box will be different, experiment with positions to find a nice compact solution.

For clean edges I used a rotary tool, but a hacksaw or sharp hobby knife would also work. These tools are dangerious, so be safe when cutting and wear appropriate safety equipment.

Step 4: Stuff Components

After wiring your components and cutting openings in your hobby box it's time to stuff the former in the latter.
Use hot glue to hold everything in place, ensuring that the motor heads are clearly exposed.

Next, place the rubber grommets on each head, once installed the grommets should be lightly touching or have a slight gap between them. If the grommets have too much friction the motors won't turn and if the gap is too large your airplanes won't get any traction. Fine tune as necessary to ensure smooth, unhindered operation.

Step 5: Add Guide Rails

These motors are tiny but powerful, so powerful that guide rails had to be included to keep the plane on desired trajectory and not getting whipped in some random direction. Rigid, thin guide rails were cut from scrap plastic and placed inside of motor heads, under the grommets. The guide rails direct the airplane into the pinch point and out the other side, directing the plane towards where ever you point it.

With the guide rails installed you're all done, put some fresh batteries in your launcher and test it out!

Did you make your own electric paper airplane launcher? Place a picture of your version of this project in the comments below.

Have fun! Happy making :)