Here's how to build an electric paper plane launcher.
We've worked on this design for a while, whittling it down to a minimum number of parts and doing our best to eliminate room for error where we can. That said, you will still need to be careful and precise while building this one to get the best result. You may even have to make a couple of adjustments here and there after building it to get it flinging planes just right.
Certain types of paper plane will work better than others. There are instructions for a plane that works well and some general guidelines for making planes at the end — you'll have to experiment a little with plane designs to get the best results, but when it does work, it really works!
So remember that this is a projectile launcher. It can launch projectiles (paper planes) pretty fast. The projectiles have pointy ends. NEVER AIM THIS AT PEOPLE OR PETS! Eyeballs are great! Look after them!
You're probably wondering how it works. Have you ever seen a baseball pitching machine or tennis ball launcher? No? What about the mechanism inside one of those battery powered Nerf guns? No? Okay...
The launcher uses two wheels with grippy rubber tyres, both spinning very fast in opposite directions. The left one spins anticlockwise, and the right one spins clockwise. The wheels are close together, but not touching. When the nose of a paper plane is introduced, the wheels pinch it and sling the plane forwards.
In this design, the longer pieces of bamboo form a nice channel to guide the bottom of the plane in a straight line.
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.
Step 1: LET'S GET ORGANISED
Here's what you're going to need to build this thing. You might end up using some different parts to those listed here. We'll tell you what to do in that case. We sell some of these parts in MAKESHOP if you are in Dublin. We have provided links to some online sources too.
- 2X high speed DC hobby motors like this, this or this one (note higher voltage)
- 2X pulleys or wheels to fit electric motor. We use this type or these ones.
- 2X rubber tyres for wheels like these or these.
- 2X adaptors to fit wheels to motor shaft. We used iron beads like these.
- 2X approximately 15cm lengths of straight, smooth bamboo (we used a single piece split down the middle)
- 2X 7cm lengths of split bamboo (note that the length of this piece of bamboo depends on the diameter of your wheels; make it one and a half wheel diameters long to be safe!)
- 1X double AA/LR6 battery clip (or larger if motor requires more than 3V). Like this.
- 2X AA/LR6 batteries (or more if required)
- 1X slide/toggle switch
- 2X 7cm lengths of hookup wire
- Hot glue gun and glue
- Wire cutter / side cutter
- Wire stripper
- Craft knife (optional)
- Soldering iron (optional)
A note about the parts used:
You may end up using different wheels to the ones we have used. Any hobby/RC wheel with a smooth rubber tyre should work. The total diameter should probably be 5cm or larger. We had to make a little adaptor to fit the wheel, which has a 4mm centre hole, on to the 2mm shaft of the motor. You might be able to find a ready made adaptor or wheels which fit snugly onto the motor shaft.
Step 2: LET'S PUT THE MOTORS AND WHEELS TOGETHER
We could have hot-glued these wheels onto the motors, but that approach often makes for a wobbly wheel. The best paper plane launchers have wheels that spin smoothly.
To fit our particular wheels snugly onto the shafts of our motors, we made a little adaptor (also known as a shim) from an iron-on bead. You could also use a section from the empty ink tube of a ballpoint pen if you cut a small slit in it.
Here's how we adapted it:
Using a craft knife, carefully cut out a little section of the adaptor (in our case, the iron-on bead), as shown.
Press the adaptor onto the wheel.
Pop the wheel onto the motor; you might want to use a tiny bit of hot glue. Don't push it on too far or the shaft will poking out the other side of the wheel.
Give it a spin to make sure it isn't too wobbly.
- Do the same with the other motor and wheel. Make sure both wheels are pushed onto the motor shafts so that they both sit the same distance from the bodies of their motors.
Step 3: LET'S MAKE THE LAUNCHER MECHANISM
Now we're going to assemble the part that will grab and launch the plane. It's very important to get the spacing between the wheels right for this step. Too close, and the plane will get stuck; too far apart, and the launcher won't grip the plane well enough.
- Put the tyres on the wheels, and place both wheels flat on a table or other flat space. You want a 1mm to 1.5mm gap between the two tyres, like in the picture.
- Get one of your shorter pieces of bamboo and put a blob of glue where each motor will attach — note that the length of this piece of bamboo depends on the diameter of your wheels. Make it one and a half wheel diameters long to be safe!
- Being careful not to move the wheels and, keeping the bamboo parallel to the table, glue the bamboo piece across both motors to brace them.
- Make sure you still have the small gap between the tyres before gluing another piece of bamboo at the same height on the other side of the motors.
Be careful not to get glue inside the holes on the sides of the motor — this can jam the motor.
Step 4: LET'S MAKE THE BODY OF THE PLANE LAUNCHER
Time to build the handle of the plane launcher and attach it to the launcher mechanism. We'll be using the battery pack as the piece that holds the parts together.
- Lay the longer pieces of bamboo next to each other, with their flat sides facing up. Put glue on the one side of the outside of the battery pack, as shown.
- Glue the battery pack in position, halfway along the bamboo, so that it holds the two pieces of bamboo in place. This is the handle.
- Put some glue on the end of the battery clip that doesn't have wires protruding from it.
- Slide the launcher onto the handle so that bamboo of the handle sits against the bamboo of the launcher mechanism.
- Make sure that the gap between the wheels lines up nicely with the gap between the two pieces of bamboo in the handle as you press the launcher mechanism into the glue.
- Add more glue across the bamboo of the handle and launcher mechanism to reinforce it.
Step 5: LET'S WIRE IT UP
Now we're going to wire up the motors and battery pack, and add a switch. We want to make the motors spin in the right direction so that they will grab the plane and fling it forwards. The motor will spin clockwise if the battery is connected one way, and it will spin anticlockwise if connected the other way (i.e. if the polarity is reversed). Follow these six steps carefully one by one.
- Test which way we need wire the first motor:
- Hold the launcher upside down, with the motors facing you and the battery holder towards the bottom, like it is in the picture.
- Hook the wires from the battery holder up to the tabs on the bottom of the left motor so that it spins anticlockwise. See the orange arrows in the picture.
- Take note of which wire you connected to which tab to get it to spin anticlockwise.
- Note the tab you connected the red wire to as positive, or +.
- Note the tab you connected the black wire to as negative, or -.
- Test which way we need to wire the second motor:
- We want the right motor to spin clockwise. Check the picture.
- Again, take note of which terminal needs to be negative and which needs to be positive.
- Wiring the motors together — negative terminals:
- Leave the black (negative) wire attached to the motor on the right.
- Disconnect the red (positive) wire.
- Connect the negative terminals of the motors with a length of wire.
- Wiring the motors together — positive terminals:
- Get another piece of hookup wire and connect the positive terminals of the motors together.
- Adding the switch:
- Decide where you want to put the switch; we're just gluing it onto the bottom of the battery back.
- Cut the red wire so that you can attach one end to the centre pin of the switch.
- Glue the switch in position.
- Wiring the switch:
- Connect the red wire from the battery pack to the centre pin of the switch.
- Use the piece of red wire that you just cut off to connect one of the side pins on the switch to one of the positive motor terminals.
- Note that the switch pictured has two rows of three tabs (called Double Pole Double Throw). We are ignoring one of the rows. Your switch might only have one row, or maybe even just two tabs.
Check that both motors are spinning in the correct direction (see first image). If one of them is spinning in the wrong direction, swap its wires around.
You can solder the wires in place at this point if you like — just make sure that both motors are spinning in the correct direction first!
Step 6: LET'S MAKE a PAPER PLANE
Some paper plane designs are going to work better with this launcher than others.
You can try some different types out for yourself, but here's some guidelines for the undercarriage of the paper plane — i.e. the part you would pinch if you were throwing the plane by hand.
- Make sure it's parallel to the wings.
- Make sure it's deep enough so that the wings won't crash into the launcher wheels.
The picture shows a paper plane design that we already know works really well with this launcher.
- Fold an A4 sheet of paper in half along its length.
- Fold the corners of one end inwards to the centre line.
- Double this fold to the centre line, as shown.
- Repeat on the other side.
- Fold the wings back on themselves to create a parallel keel.
- This is a pointy plane — cut a bit off the front to blunt it a little.
Step 7: LET'S LAUNCH SOME PLANES!
Launching planes might take a little practice, and you need a good plane for it to launch well. Keep experimenting.
To launch a plane:
MAKE SURE YOU AREN'T AIMING AT A PERSON OR PET!
- Hold the plane launcher out in front of you with the motors and wheels towards the front.
- Turn on the launcher and let the wheels spin up to full speed.
- Get your plane ready, and slide it gently forward along the groove until it sits just behind the wheels — as you can see in the pictures.
- Take aim ...
- When you're ready to launch, give the plane a quick little tap forwards so it gets caught in the wheels and ZOOM! ... watch the hands carefully in the gif above.
- See if you can get your planes to roll or do loops by slightly bending the backs of the wings.