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There is nothing as quintessentially summer as a classic water balloon fight. But now you’re going to be ready when that H20 chaos consumes the block. Because this year, you’ll be armed with the Ludgar the War Wolf of water balloon artillery.
Built in an afternoon for around $55 in materials, this balloon launcher will toss water bombs on your neighborly foes from a long ways off. It’s also a great project to do with this little mischief maker in your life.
⚠️ As with any weapon of mass aquatic destruction, it’s probably a good idea to wear protective eyewear, especially when high-tension surgical tubing is involved.
These Tools Will Help
Plans and Materials
Build the Frame
First, drill a 5⁄16-in. hole in the center of the 2-in. side of each leg, 3 in. from one end.
On the narrow side of two legs, mark 12 inches from the end opposite the holes. Align the bottom of a plywood piece with the marks, hold the outer edges of the plywood and the legs flush, and drill three 1⁄8-in. pilot holes on each side, 3⁄8-in. from the edge. Then, screw the plywood to the legs. Mark the legs 6 in. from the top of the plywood. Line up the bottom edge of the remaining piece of plywood on the marks and fasten it to the legs. You’ve just made the launcher’s front. Another Great Project for Kids!
Now lay the other two legs on a level surface, parallel and with the outer edges 46 1⁄2 inches apart. Mark the narrow side of each leg 18 inches from the bottom, line up the crossbeam with the marks, and fasten it with one screw on each side. This will be the back.
Connect the two assemblies by fitting the narrower one inside the other, lining up the 5⁄16-inch holes and putting the eyebolts through the holes, with the eye on the inside. Use three washers per side, one each between the eye and the inside leg, the two legs, and the wingnut and the outer leg. Screw an eye lagbolt into each leg, 36 inches from bottom. Use the carabiners and chains to connect the eyebolts, and now you’ve made a water catapult that’d make any medieval monarch jealous.
Make the Water Balloon Holder
But your work isn’t done yet, you’ll need something to hold those latex and rubber bombs.
First, drill two 1⁄2-inch holes opposite each other into a funnel, 1 inch from top; fit grommets into holes. Slide 6-inch piece of hose onto rope; push rope’s ends through narrow end of funnel and hole in fender washer. Tie the ends together.
Tie two 24-inch lengths of surgical tubing through the grommets and the eyebolts. Stand behind the frame, grasp the balloon holder’s handle, and pull down at an angle. Load the funnel with a water balloon—and let it fly. We hold no responsibility for the destruction that follows.