In a world where 3D printers can make everything from prosthetic limbs to pizza, one engineer has taken the technology to a new, slightly concerning level: tattooing human skin. Meet Emily Yarid, better known as [Emily The Engineer], a YouTuber who has made a name for herself by pushing the boundaries of DIY tech. Her latest project? Transforming a 3D printer into a functional tattoo machine. And yes, it involves needles, ink, and a brave volunteer.

“This is not for the faint of heart,” Emily warns in her video, about 10 minutes in. By then, you’ve already seen enough to know she’s not kidding. What started as a quirky idea — what if a 3D printer could tattoo? — has turned into a side quest meant to see how far you can push a machine designed for plastic into the realm of body art.

DIY Tattoo Machine

Emily’s project began with a standard Creality Ender-7 3D printer. But instead of extruding plastic filament, she swapped the nozzle for a tattoo gun. The printer’s arm, which usually moves in three dimensions to build objects layer by layer, was reprogrammed to operate in two dimensions — which is much better suited for drawing on skin.

But this wasn’t just a simple hardware swap. Emily had to hack the printer’s firmware to bypass safety checks, like temperature controls, which are irrelevant when you’re not melting plastic. She also added a spring to the tattoo gun arm to account for the natural variations in skin height. After all, human legs aren’t as flat as a printer’s build plate.

Perhaps the most critical addition was an emergency solenoid system — a panic button to stop the machine mid-tattoo. “It’s like an eject button for your skin,” Emily joked. This feature was non-negotiable. As anyone who’s sat through a tattoo session knows, needles and pain go hand in hand. The last thing you want is a machine that won’t stop.

The result? A Frankenstein-esque contraption that’s equal parts ingenious and alarming. Emily’s volunteer, fellow YouTuber Dan from BuildDanielBuild, bravely offered his leg as the canvas. They settled on a simple, one-word tattoo in blue ink: “LEG.”

Would You Try It?

At this point, you might be wondering: Why?  For Emily, it’s about the thrill of innovation. “I love pushing the limits of what these machines can do,” she says.

Previously, Emily used 3D printers to build everything from cosplay costumes to functional boats.

But let’s be clear: this won’t ever replace a tattoo artist nor does it sound like a suitable tool for the artists.

That hasn’t stopped others from trying. Companies like Blackdot in Austin, Texas, have been working on automated tattoo machines for years. But their devices are expensive and still require human oversight. Emily’s project, on the other hand, is a reminder of what’s possible with a little creativity and a lot of nerve.

So, should you try this at home? Absolutely not. But should you watch Emily’s video and marvel at her ingenuity? Absolutely. Just maybe don’t do it while sitting in a tattoo parlor.

As for Dan, the proud owner of a robot-made “LEG” tattoo, he seems happy with the results. “It’s definitely a conversation starter,” he says. And really, isn’t that what tattoos are all about?