The would-be invader of a mediaeval kingdom could expect to face some stern opposition from a variety of formidable weaponry. Making modern versions of these deadly curiosities seems to be a popular pursuit, and the bug has bitten [Turbo Conquering Mega Eagle], who’s created what he calls a “Stonebow”, a crossbow on steroids that fires stones or large ball bearings with considerable force.
It uses a couple of leaves from automotive springs, mounted in a welded steel riser with two strings and a pouch for the projectile. The barrel is an oak fencing post, and at its other end is a cocking lever which also forms a stock, and a cleverly designed trigger mechanism. The projectile is loaded, the bow is cocked, and it is fired at a scrap Land Rover radiator in which it places a satisfying impact mark.
Despite two successful firings it’s evident that so much force isn’t easy to contain. The crimps that secure the strings aren’t up to the job, and neither is the oak fence post, which has cracked at the end. We trust that our Essex hacker friend will return having fixed these flaws, and more defenceless scrap car parts will be sacrificed for our entertainment.
We’ve featured [Turbo Conquering Mega Eagle] before, most recently building a mini-bike for his youngsters. Meanwhile, enjoy the Stonebow in the video below the break.
Continue reading “This Crossbow Fires Cannonballs!”
[James], aka [Turbo Conquering Mega Eagle], is not your typical Hackaday poster boy. Most of his builds have a “Junkyard Wars” vibe, and he’d clearly be a good man to have around in a zombie apocalypse. Especially if the undead start driving tanks around, for which purpose his current anti-tank compound crossbow is apparently being developed.
At its present prototype phase, [James]’ weapon o’ doom looks more fearsome than it actually is. But that’s OK — we’re all about iterative development here. Using leaf springs from a Toyota Hi-Lux truck, this crossbow can store a lot of energy, which is amplified by ludicrously large aluminum cams. [James] put a lot of effort into designing a stock that can deal with these forces, ending up with a composite design of laminated wood and metal. He put a lot of care into the trigger mechanism too, and the receiver sports not only a custom pistol grip cast from aluminum from his fire extinguisher foundry, but a hand-made Picatinny rail for mounting optics. Test shots near the end of the video below give a hint at the power this fully armed and operational crossbow will eventually have. The goal is to disable a running car by penetrating the engine block, and we’re looking forward to that snuff film.
If rubber band-powered crossbows are more your speed, take you pick — fully automatic, 3D-printed, or human-launching.
Continue reading “Junkyard Crossbow Aims To Be A Car Killer”
You’ve got to enjoy any project where the hacker clearly loves what he or she is doing. And when the project is as cool as a motor-driven, rubber band powered, fully automatic crossbow, it’s hard not to laugh along.
A full-auto crossbow is no mean feat, and it took a man with a love for rubber-powered firearms to get it right. [JoergSprave]’s design is based on a rack-and-pinion system and executed mainly in plywood. The main pinion gear is a composite of aluminum and wood, in a bid to increase the life of the mechanism and to properly deal with the forces involved. The pinion, turned by a powerful electric drill, drives the rack back and locks the carrier under the 30-bolt magazine. A rubber-powered follower forces a bolt down and a cam on the pinion trips the sear, the bolt is fired and the cycle continues.
We slowed the video down a bit and it looked to us like the cyclical rate of fire was about 7 rounds per second, or a respectable 420 rounds per minute. Pretty powerful, too, and the accuracy isn’t bad either.
We’ve seen [Joerg]’s inventions before, like this soda bottle Gatling arrow launcher, or his ridiculous machete launcher. We hope he keeps having fun and letting us watch.
Continue reading “Full-Auto Crossbow Rocks And Rolls On Rubber Bands And Electric Drill”
Say you have a team of French engineers, a lake in the summer, a wizened old machinist, and some gigantic bungee cords. What would you build? The answer is clear, a human-launching crossbow. (Video, and making-of embedded below.)
You can start out watching the promo video because it looks like a lot of fun, but don’t leave without watching the engineering video. What looks like a redneck contraption turns out to be painstakingly built, and probably not entirely a death trap. The [Rad Cow] team even went so far as to purchase metal cart wheels.
Everyone else on the Intertubes would tell you not to do this at home. We say go for it. That is, draw up reasonable plans, work with an obviously competent machinist, and make something silly. It’s not going to be more dangerous than the stuff that [Furze] pulls off.
Continue reading “How To Make A Human Crossbow”
As it turns out, it’s not feasible to print an entire crossbow yet. But [Dan]’s crossbow build does a good job of leveraging what a 3D printer is good at. Most of the printed parts reside in the crossbow’s trigger group, and the diagrams in the write-up clearly show how the trigger, sear and safety all interact. Particularly nice is the automatic nature of the safety, which is engaged by drawing back the string. We also like the printed spring that keeps the quarrel in place on the bridle, and the Picatinny rail for mounting a scope. Non-printed parts include the aluminum tubes used in the stocks, and the bow itself, a composite design with fiberglass rods inside PVC pipe. The video below shows the crossbow in action, and it looks pretty powerful.
Actually, we’ll partially retract our earlier dismissal of entirely 3D-printed crossbows, but [Dan]’s version is a lot more practical and useful than this model. And for a more traditional crossbow design, check out this entirely hand-made crossbow.
Continue reading “Powerful Crossbow Is Almost Entirely 3D Printed”
Curious if he could, [Gignathiosis] decided he wanted to try building his own crossbow. So he did.
He built the entire weapon using hand-tools, minus a drill for the holes, though he could have gotten a brace for that bit. The most impressive part is that he used a hacksaw to carve up a block of aluminum into the trigger release — a job normally done by a mill. The only modern components on the bow is the limb (which he ordered off Amazon) and a bit of tactical rail for his scope. The end result is a gorgeous hand-made cross-bow.
There’s just something so satisfying about manufacturing old technology using hand tools. It probably has something to do with the thought that, if you ended up back in time somehow, you could use your 21st century knowledge as a hacker to change the world… and maybe become a ruler — or a magician — as long as you don’t do something that results in your entire existence vanishing.
Though if you really wanted to mess up history — take back a fully-automatic crossbow with you instead.
Centuries ago, craftsmen and smiths of all sort spent hundreds of hours crafting a crossbow. From the fine craftsmanship that went into making the bow to the impeccable smithing a windlass requires, a lot of effort went into building a machine of war. Since [Chris] has a 3D printer, he figured he could do just as well as these long-dead craftsmen and fabricate a crossbow in under a day.
What’s really interesting about [Chris]’ crossbow is that it is only a single piece of plastic. The bow is integrated into the stock, and the trigger works by some creative CAD design that takes advantage of the bendability of plastic. The only thing required to shoot a bolt from this crossbow is a piece of string. That, and a few chopsticks.
He won’t be taking part in any sieges, but [Chris]’ weapon is more than capable of shooting a bolt across a room or launching a balsa wood airplane. You can see an example of this after the break.
Continue reading “One Piece, 3D Printed Crossbow”