This prank works by cutting a hole in the bottom of a can identical to your friend/colleague's favourite drink and installing a plastic cup inside. When they're not looking you can swap out their drink for your modified one and sit back and watch the confusion/laughter/anger.
It works best when they're sitting down at a desk or on a sofa as the water will fall out when they lower it after trying to take a drink, causing water to fall on their lap.
It is intended as an easier to make version of my other coke can prank, the Laughing Coke Can as it requires no electronics knowledge, just 15 spare minutes.
- 2 drinks cans
- superglue (optional)
- double sided tape
- large/tall cap or container
- syringe (not needle)
- 5cm tubing (or USB cable)
- hacksaw blade
- punch (or thick nail)
- tin snips (or strong scissors)
Step 1: Make a Hole
With the punch and hammer, make a hole near the edge big enough to insert the hacksaw blade.
Holding the hacksaw blade carefully, saw around in a circle close to the rim of the can. Get as close as you can to the rim near the side that has the drinking hole on it.
Step 2: Add a Container
Anything less than the diameter of the hole in the bottom of your can (44mm) would be good. Mine's the cap from a sun cream bottle. You could use anything of that size. e.g plastic shot glass, plastic measuring cups from Schweppes soft drinks, large bottle caps or a film canister (if you're old enough to remember those). The more liquid it holds the better.
I decided to mount it to a piece of another can so I could get it to stick well before I put it in the can. Previous attempts without the can segment resulted in wonky or wobbly containers. This way I could check it was firmly attached and once the can segment was inside, it could only stick in the right place.
With some tin snips or very strong scissors, cut down the length of the second can. Remove the top and bottom to leave you with a roll of aluminium. Neaten this up with your tin snips or scissors.
I attached the cap to the can segment using super glue and stuck double sided tape to the back of the can segment.
Before removing the tape backing, check it will fit through the hole then remove the tape backing and insert through the hole in the bottom of the can. When it's stuck you want the water container to be situated on the side opposite to the drinking hole.
Step 3: Fill 'er Up
Take a length of old wire. Mine was a short length of USB wire. Pull the wires and protective sheath from the middle and save for another project.
Push the tube over the end of the syringe. If it's slightly too small, warm it with a lighter to make it easier to fit.
To fill, push your filler through the hole in the top of the can and make sure the end of the tube is in the container. Fill from a tap until the container is full.
You're now ready to swap it out for your friend/colleague's can. Make sure you swap like for like cans or they'll notice straight away. If at a party, why not offer your mate a beer? You can fit a taller container in a beer can, and more water means a wetter friend! If they're sitting down they'll get more on them.