Introduction: Laughing Coke Can Prank

This instructable details how to make a coke can prank (or any drinks can) that will laugh when picked up and tilted towards the mouth.

It's a great prank to play on friends/colleagues/family when you get a chance to swap out their drink for your rigged one!

I tried to make this ible as simple as possible to make it accessible to as many people as possible. Where I could I taped instead of soldered. Info in the steps should be transferable to most other noise making toys!


- drinks can
- toy that laughs
- tilt switch
- batteries
- electrical tape
- solder


- wire strippers
- soldering iron
- hammer
- punch or nail
- hacksaw blade or scissors
- pliers

Step 1: Opening Up the Can

Turn over the can. For items required in this step, see picture two.

With a punch or nail, pierce the bottom of the coke can. Wiggle it until the hole is wide enough to insert a hacksaw blade.

Gripping the hacksaw blade in the pliers (or your fingers if you're hardcore), cut a slit. Cut two more slits so the bottom of the can is divided into six. Once the hole is larger, using a strong pair of scissors may be easier than the hacksaw blade.

Carefully push the six tabs inwards to make a hole. Dividing the bottom of the can more is better, it will cause the rim to bend less and your can won't wobble then.

Step 2: Canibalise

Gut the toy of your choice. Mine laughs manically when you squeeze it. I cut off the flashing LED and saved it for another project and before continuing checked it fitted in the can.

Step 3: Power

Having cut away the battery holder that was too big to fit in the can, I taped two AA batteries together and connected them in series with a piece of wire and some tape. This will supply the circuit board with the 3V it needs. I attached this to the circuit board and pressed the button to check it worked.

Having checked it still works, detach the batteries.

Step 4: Installing the Tilt Switch

Rip off the contact switch. This will be replaced by the tilt switch so when your victim/friend/colleague goes to take a swig, it laughs.

The circuit is completed when the current flows across the interlocking lines. Soldering the contact switch either side of this will complete the circuit when the tilt switch is.... well... tilted!

Use some helping hands (not a friend, it will get hot!) to keep the tilt switch in the correct position while you solder it on. Be careful not to get solder across the contacts!

Step 5: Add a Toggle Switch

This goes between the board and the batteries so you can turn it off while you're carrying it.

I cut the positive wire in half and soldered in the switch. Adding some electrical tape around the contacts will stop them shorting out against each other.

Tape it to the board so that when inserted into the can it can be accessed from the hole in the bottom.

Step 6: Add the Batteries

Tape the batteries to the other side with the visible contacts facing down. Tape the positive and negative leads to the correct terminals. Remember to get them the right way round or it more than likely won't work!

The magnet in the speaker should hold it conveniently to the batteries on the end that the tilt switch is located so that it's pointing upwards towards the drinking hole.

Add double sided tape to the back of the batteries and insert through the hole in the bottom of the can. Stick it to the wall opposite from the drinking hole, then as your victim picks up the can and tilts it towards them the can will laugh/howl manically at them!

Step 7: Operation (& Prizes)

Install the circuit in a brand of drink that you know your friend or colleague frequently drinks.

When they leave their desk/room to do something, quickly swap out their real can of soft drink for your rigged one. Turn it on and..... wait. If you're mean, drink their real can.

When they return and take an unsuspecting swig, the can will burst out laughing, hopefully causing them a fright or to drop it.


I'm offering a cookie patch to the first three people to post a picture of the innards of their prank can and a video of it in operation on their unsuspecting victim (no fakes please!). You'll also get a mention edited into this step with a link to your video.
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