How to Build a Snowball Catapult for Kids

In England, catapults were first used in 1216.

Building a snowball catapult is a hands-on way to prepare for the winter while spending quality time with your children as well as teaching them woodworking basics and simple physics. During the winter, they provide a fun opportunity for neighborhood competitions. A 4-foot-long catapult powered by a bungee cord has a range of 45 to 65 feet. You only need a few basic hand tools and a power drill to construct a snowball catapult.

Things You'll Need

• Four 2-by-4-by-72-inch lumbers
• Foxtail saw
• 3/4-inch-thick plywood, 1 foot wide by 2 feet long
• Hammer
• Box of 3-inch nails
• Box of 2-inch nails
• 4-inch- wide metal hinge
• Power drill
• Phillips-head drill bit
• 6 3-inch wood screws
• 4-foot-long bungee cord
• 3/4-inch eye hook
• 4 U-shaped nails

Instructions

Frame

1. Cut the 2-by-4-inch lumber with the foxtail saw. You need two 24-inch lengths and two 48-inch lengths for the support frame, three 24-inch lengths for the uprights and one 48-inch length for the throwing arm.

2. Cut the plywood sheet into two 1-foot squares. One square is the throwing arm's pan. Cut the other square into two right triangles. These are the upright beams' support brackets.

3. Place two 48-inch lumbers flat on your work surface so that they are parallel and their outside edges are 24 inches apart. Place two 24-inch lumbers across the 48-inch lumber ends, making sure the four pieces form a perfect rectangle. Nail the rectangle together, using four nails for each corner.

Upright Beams

1. Lay two 24-inch upright beam lumbers flat on your work surface. Center a support bracket on the end of each upright beam so that the right angle points to its top and the base hangs over the bottom exactly 2 inches.

2. Place each upright beam onto the frame so that the tip of the support bracket's base is flush with the frame's front end. Drive three 2 1/2-inch nails through each support bracket into the frame. Drive three 3-inch nails through the frame into each upright.

3. Place the remaining 24-inch lumber across the top ends of the upright beams. Drive three 3-inch nails through the ends of this beam into the upright beams.

Throwing Arm

1. Lay the throwing arm flat on your work surface. Center the 1-foot plywood square on the throwing arm so that the square's edge is flush with the throwing arm's end. Attach the square to the throwing arm by driving four 2 1/2-inch nails through the square into the throwing arm.

2. Twist the C-hook into the throwing arm, 2 inches below the plywood square. The hook's end must point toward the throwing arm's top when it is fully screwed in.

3. Open the hinge. Place it against the 4-inch side of the throwing arm's bottom end. Attach the hinge by driving three wood screws through the holes into the throwing arm.

Final Assembly

1. Slide the throwing arm under the upright beams' crossbar. Center the hinge's free side on the rear of the frame's front beam. Fasten it to the beam with three wood screws.

2. Tie bungee cord's ends to the frame's front corners. Keep each end in place by placing two U-shaped nails over it and hammering them into the frame.

3. Raise the throwing arm to the cross bar. Stretch the bungee cord over the cross bar. Hook it into the C-hook.

Tips & Warnings

• You can transport the catapult more easily when two people carry it.

• This project requires the assistance of a grown-up.

• Never fire a snowball catapult at people, animals or things that can break easily.

References

• Storm the Castle; The Sled-a-Pult; 2011
• "The Art of the Catapult: Build Greek Ballistae, Roman Onagers, English Trebuchets, and More Ancient Artillery;" William Gurstelle; 2004
• "Construct a Catapult;" Lee Pullis; 2000
• Middle Ages: Catapults