The lighter side of 3D printing

From printing out realistic-looking faux bananas to leaving miniature skeletons in a friend’s garden, the 3D printing community thrives on hilarious projects and absurd creations. These funny stories and print ideas show that while 3D printers can be practical, they are ultimately engines for ridiculous jokes.

The “Rock-in-the-Box” Prank

One classic internet favorite involves printing endless variations of Dwayne “The Rock” Johnson’s head and secretly placing them around the house. Community members have printed “Rocking Chairs” (a chair made out of his head), giant “Rock-heads,” or the “Rock in the Box”—a pop-up jack-in-the-box prank that startles unsuspecting victims when opened. [1]

The Retractable Banana Sword

If you are looking for the true pinnacle of 3D printing, it might just be the retractable banana sword. One enthusiast printed a five-foot-long retractable sword using “stone” filament, which gave the blade a slightly rotten banana hue. Walking around with a giant, terrifyingly loud, retractable yellow blade became one of their favorite experiences, entirely eclipsing any practical objects they had ever printed.

The Fart Filter and Smoke Alarm Hack

A famous practical joke design available on community platforms is the “Fart Filter”—a custom print attachment meant to be added to prank boxes. For another hilarious but genius life hack, a user grew tired of their wife asking them to climb up and push the button on a continuously beeping smoke detector. They instead 3D printed a “chopstick hat” to press the button from the safety of the floor, later upgrading to a specialized broom-mount to silence the alarm while comfortably standing.

The Hair Prank

One of the most viral modern 3D printing stories involves a simple, everyday “hair prank”. People are using desktop printers to model incredibly detailed fake insects and spiders. They then balance these prints directly onto the underside of a ceiling fan, wait for an unsuspecting roommate or family member to turn the fan on, and watch as a terrifying “spider” flings at them in a blur.

Funny Print Ideas to Try

If you want to make your friends laugh, you can check out these quirky and hilarious files:

• “Cat Vomit” Wet Floor Sign: A miniature hazard sign to place by your cat’s favorite trouble spot.
• Cat Crocs: 3D print actual miniature Crocs for your felines and watch them awkwardly strut around.
• Bathroom Signs: Print clever signs, like “Please do not throw cigarettes in the urinal, it makes them soggy” to hang up when friends come over. [1, 2, 3]