Trebuchet Your Boss Right In His Stupid Face With These Desktop Siege Engines

Now on Kickstarter, buy yourself a snap-together weapon of mass destruction from the Medieval days. You’ll be glad you did.

The weapons of mass destruction of the Middle Ages were siege engines. As imagined by the minds of historic geniuses like Archimedes and Leonardo Da Vinci, siege engineers were massive machines that could hurl boulders thousands of feet through the air to smash down city walls and reduce defenders into a smear of red gelatin.


Sound cool? Now you can get one for your desk, thanks to E&M Labs, a clever Californian toy company that sells snap-together siege engines like the trebuchet, catapult and ballista, each of which is capable of hurling a toy ball over 70 feet. You’ll make that tyrant boss of yours rue the day he ever signed off on that open office floor plan.

The E and M in E&M Labs are Evan Murphy and Michael Woods. As fellow students at Caltech, Murphy and Woods talked about coming up with the next multi-billion dollar Silicon Valley start-up. Three years after graduation, Wood showed up on Murphy’s doorstep: “You remember how I used to say that one day, I’d have a great startup idea? Today’s that day.” And so the two quit their jobs and moved to Silicon Valley, where they launched a service to prioritize email in your inbox–just months before Gmail gave its millions of users Priority Inbox for free. It was back to the drawing board, and on that drawing board, Woods started drawing siege engines.

“Mike had this idea for a desktop trebuchet you could just snap together,” Murphy tells Co.Design. “He figured that if you cut the pieces precisely enough, you could make it very powerful even though it was only like 1:50 scale. So we mocked up a prototype at a local machining shop, and threw it up on this new site we’d heard about called Kickstarter.”

That was in 2010. Pretty soon, E&M Labs’ Trebuchette was one of the earliest Kickstarter success stories, racking up $100,000 in pre-orders from eager office marauders. The siege engine stands 16 inches tall, can hurl a plastic ball a range of 25 feet, and snaps together with no tools or glue in about 10 minutes. But the Trebuchette was just the beginning. Now on Kickstarter, E&M Labs is raising the money for follow-up siege engines: a Ballista and a Catapult, respectively.

Like the Trebuchette, the Ballista and Catapult are snap-together siege engines that can hurl projectiles across the office. “The snap-together aspect is important,” says Murphy. “It’s just no fun watching glue dry. If you get a do-it-yourself siege engine kit in the mail, you want to be able to use it right away.” Nevertheless, perfecting a joint that could snap-together yet withstand the pull and torque of a siege engine was a daunting task, requiring over two hundred prototypes until Wood found a solution that worked just right.


Besides personal preference, the major distinction between the Trebuchette and the Catapult and Ballista is the physical principles behind them. Whether flinging boulders or bouncy balls through the air, the Trebuchette functions because it harnesses the force of gravity, while catapults and ballistas work by accumulating tension, which is then suddenly released. In ancient times, this was accomplished with a piece of wood or metal, but in the case of E&M Labs’ desktop models, it’s all accomplished with a bungee rope.

So who is this for? While E&M Labs knows they’re selling more than a few desktop siege engines to fun-loving or frustrated cubicle jockeys, the demographic they really want to reach is engineering dorks.

“The thing that’s cool about siege engines is they’re just filled with physics,” says Wood. “They’re very clear examples of real engineering and physical principles. So are cars, but unlike cars, none of the principles are hidden away. So when you pull the arms of a ballista back, you can see the strings twisting, the force accumulating. The whole device is exposed for you to see. It’s like engineering porn.”

If engineering is your porn, or you just like shooting people in the face with siege engines, E&M Labs is now selling the Trebuchette on its official site for $39.95. The Catapult and Ballista, meanwhile, are now available for pre-order on Kickstarter, with delivery guaranteed by Christmas.