Introduction: 3 Ways to Make Cardboard PinBall Sensors

About: Hi! I'm Natasha. I'm a Tech-Crafter, Maker, and the Designer of TechnoChic DIY Tech-Craft Kits. Technology should be chic!

Making your own PinBall game - or any game for that matter - can be more fun than the game itself!

For my DIY Pinball Machine, I thought making switches to sense a metal pinball would be easy - I would simply have the ball bridge a gap between two pieces of conductive tape connected to a microcontroller. Simple, right?


It was tougher than I thought. Just touching the tape wasn't enough, and so I had to create a situation where the ball was resting solely on the connection for long enough to trigger or a situation where the ball was forcing a solid connection with gravity. After many many prototypes, I settled on the three designs that I'll show you below.

I hope this inspires you to make your own cardboard game! These cardboard sensor techniques can be applied to PinBall, mini-golf, skeeball, marble runs, or games that have yet to be invented!



  • Micro:bit Bit Board Shield
  • 7 Segment Display to make a scoreboard

Step 1: The Cardboard Train Track Switch

This switch senses the location of the ball as it travels down a track.
  • Create a cardboard "train track" with two pieces of cardboard glued parallel to each other. They can be straight, or curved as you see in the example.
    • If you are making a curved track, peel one side of the paper off of the cardboard to allow the corrugation to bend easily (make cuts across the corrugation, not parallel to it!).
    • I used super glue to create the curve, adhering a little bit of the track at a time and holding it in place as the glue set (about 10 seconds.) The same technique can be used for hot glue, but hot glue is more visible in the finished design.
    • After you've laid the first track, slowly create the second track parallel to the first one. Test the distance between the two tracks as you go to be sure that the ball doesn't fall in or out of the track.
  • To make the switch, lay one piece of Maker Tape over one of the tracks, and continue sticking the Maker Tape until it runs over the edge of the cardboard. This will make it easy to clip an alligator clip to it.
  • Repeat with another piece of Maker Tape on the other track, making sure it doesn't touch the first piece.
  • When the ball rolls down the track, it will make a connection between the two pieces and close the switch (adjust the placement of the tape to ensure a good connection).

The fun thing about this switch is that you can place many switches along the track. You could connect them all to the same microcontroller pin to activate a score increase, or wire them to separate pins to activate different outputs as well! The possibilities are endless.

Step 2: The Cardboard Draw Bridge Switch

This switch uses the gravity of the ball to connect the Maker Tape and close the switch.
  • Cut out a small rectangle of cardboard the width of your tape and about 1/2 inch tall.
  • Tape the rectangle to the end of a piece of tape and adhere the tape where you want the drawbridge to be. Add another piece of tape to the top so that the piece sticks up and looks like a "draw bridge".
  • Cut a 1.5-inch piece of Make Tape and fold the ends over so that they don't stick (about 1/4 inch on each side). Stick it underneath the bridge as shown.
  • On the base, run a piece of maker tape to the bridge and leave a gap under the bridge before continuing.
  • Add a structure that will direct the ball over the bridge. I used two pieces of cardboard folded over to create a track that ends at the draw bridge.
  • When a ball pushes down the drawbridge, the Maker Tape's flaps will close the gap and connect the switch.

Use this cardboard switch at the end of a track or as a target for balls that fall through other obstacles.

Step 3: The Cardboard Hole Switch

This switch acts like a small basket cradling the ball and making a connection as the ball falls through a hole.
  • Create a hole in a piece of cardboard that is *slightly* larger than the ball. If you're not sure, start with the diameter of the ball and slowly increase the size of the hole until the ball falls through easily.
  • Cut 6, 1-inch pieces of Maker Tape, and fold down the first 1/4 inch so that that part doesn't stick.
  • Lay the pieces so that the non-sticky part is over the hole, three on each side. The pieces should overlap slightly as well.
  • Run a piece of maker tape to the pieces on one side of the hole, and the second piece of Maker Tape from the other side.
  • Add a cardboard backboard to direct the ball into the hole. When the ball falls through it will brush the Maker Tape and complete the circuit.

This cardboard switch is perfect for sensing any type of game where a ball goes through a hole like PinBall, Mini Golf, Skeeball, and more!

Step 4: Connect to a MicroController & Make a Game!

Use alligator clips to connect one side of the switch to (-) ground and the other side to a pin of your choice. You'll need to set the pin to "Pull Up" if that isn't the default on the microcontroller and/or code that you use.

Step 5: In Action!

I used the micro:bit, Brown Dog Gadgets bit:board, and a 7-segment display to create a scoreboard. View the code and project here.

I also incorporated these switches into a PinBox 3000 cardboard pinball machine. You can see the project here:

I hope you enjoyed this tutorial! If you want to see more of my work, you can follow me here on Instructables and on Instagram and YouTube - Please Subscribe! You can also buy tech-craft kits designed by me at

I've also included links to all of the supplies. As an Amazon Associate, I earn a small commission on purchases made through the links below, and that helps me make more tutorials like this. :)

Cardboard Speed Challenge

Second Prize in the
Cardboard Speed Challenge