Water Balloon Slingshot (in 3 Minutes)




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The kids on your block have gathered. The hoses are getting unravelled. You have three minutes before the first water balloons start flying. Four minutes tops if Tommy still can't tie knots without his mom's help. Susie and Jermaine come running to your side. "We need a slingshot" they say. You have just latex tubing and duct tape.

No problem. :)

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Step 1: Make a Tube Loop

Start with about six feet of latex tubing, which you can get from most hardware stores. Tie the two ends together with a double knot, and then cut off the extras.

2:40 to go. The older 4th graders across the street are hogging the hoses.

Step 2: Duct Tape Side Handles

Roll your duct tape around the knotted part to make a handle and keep the knot together. Then spread out your loop and find the opposite side. Use the duct tape to wrap and make a matching handle.

2:10 to go. Tommy is calling for his parents to help him with knot tying.

Step 3: Make a Duct Tape Pouch

Lay out five strips or so of duct tape face up and next to each other overlapping slightly. Put the mat underneath your tubing in the middle and fold it over so it sticks to itself. Do the same on both sides. Scrunch the top and bottom of the pouch a little bit along the tubing to make it more pocket-shaped.

1:10 to go! Turns out Tommy's mom, dad, and grandma are all balloon knot-tying wizards. Susie and Jermaine kick into gear.

Step 4: The Pullback Handle

Lay down two long strips of duct tape face up, and then put two shorter strips over them. Use the remaining sticky sides to wrap the handle around your existing pouch. Now you have a handle to pull your balloons back with. To make it sturdy, make it long enough that the two ends overlap.

10 seconds to go! Susie and Jermaine are in position. The 4th graders are sneering. Tommy's grandma has a Super Soaker and a firehose. You are calm. It's time.

Step 5: Sling Some Balloons! (and Baked Goods)

It's launching time! Tell your two friends to stand side by side holding the side handles with their hands up in the air. Put the water balloon in the pouch, and pull back by the handle. If you want maximum distance, use your remaining ten seconds to read this primer on the physics of projectile motion.

Also, when you'd like to start wooing people instead of watering them, you can put muffins or donut holes in as well. They fire great! Make sure to eat them after. Firing food into the air is great. Wasting it isn't.

If for whatever reason your friends get called in for dinner before you do, the one-person method is demonstrated in the last photo. Sure you'll look awkward, but you'll be efficient.

Have fun, be safe, make sure people consent to being launched at, and keep exploring. Can't wait to see what you make!



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    7 Discussions


    6 months ago

    What if you don't have two friends. Or any friends


    2 years ago



    3 years ago

    In college we used to make these in a similar fashion and fire snowballs over buildings for indirect fire. We had a spotter in a window directing shots for the crew on the other side. Good times.


    3 years ago

    I once equipped a 50 foot trimaran sailboat with a dozen of these using bungee cords strung in "X" shapes in the spaces between the railings on the deck, in order to participate in the final "Wednesday Night Beer Races" race of the season in Santa Cruz. It is kind of a tradition at the beer races for the last race of the year to also be a giant ship-to-ship water fight. It was so much fun, partly because we had the most firepower (waterpower?) and partly because my friend's homemade trimaran could literally run circles around the second fastest boat in the race.