How to Build a Trebuchet to Sling Pumpkins
Building a trebuchet that launches pumpkins is a creative way to salute the military machinery of the Middle Ages. While the real things were historically used as catapults during battles and wars, many model trebuchets can be constructed in less than two hours with the use of several household goods. Craft your model trebuchet with patience and care, and you'll be able to send miniature pumpkins flying high into the sky.
Things You'll Need
- Work gloves
- Safety glasses
- Measuring tape
- Saw
- 16-inch-by-2-inch-by-2-inch lumber
- 12-inch-by-2-inch-by-2-inch lumber (2)
- 10-inch-by-2-inch-by-2-inch lumber (2)
- 3-inch-by-2-inch-by-2-inch lumber (9)
- 6-inch-by-2-inch-by-2-inch lumber (2)
- 6-inch-by-6-inch plywood, cut to a right triangle (2)
- 80-grit sandpaper
- Drill
- 1/4-inch drill bit
- 1/8-inch drill bit
- Wood glue
- Permanent glue
- 1/8-inch-by-4-inch metal rod
- Heavy object (such as a Chinese Baoding ball or a wad of batteries)
- Electrical tape
- Scissors
- String
Instructions
-
-
1
Put on a pair of work gloves and safety glasses to protect skin and eyes.
-
2
Measure and cut the lumber and plywood to the dimensions listed. Sand and smooth all pieces with 80-grit sandpaper.
-
-
3
Measure three inches up from one end of the 16-inch lumber. Drill a hole through the side of the piece using the 1/4-inch bit. The 16-inch piece will act as the launch arm, anchored by the metal rod inserted through the hole.
-
4
Stand one of the 12-inch pieces on its end. Measure one inch down from the top of the piece. Drill a hole in the center about one-third of the way through the lumber using the 1/8-inch bit. Repeat for the second 12-inch piece.
-
5
Stand one of the 12-inch pieces upright so that the 1/8-inch hole is facing to the left. Position one of the triangle panels against the outside -- the side without the hole -- at the bottom of the 12-inch piece. Face the downward slope of the triangle toward you -- or in perpendicular fashion to the hole. Make sure the vertical sides of the triangle and the 12-inch lumber are flush. Bond the pieces together with wood glue.
-
6
Stand the other 12-inch piece upright so that the 1/8-inch hole is facing to the right. Position the other triangle panel against the outside -- again the side without the hole -- at the bottom. Face the downward slope of the triangle toward you as before, ensuring the vertical sides of the triangle and the 12-inch piece are flush. Bond together with wood glue.
-
7
Fill one of the holes on a 12-inch piece with permanent glue. Fit one end of the metal rod into the hole. Hold the rod in place for 60 seconds to secure the bond. Slide the 16-inch piece onto the rod. Fill the second hole on the other 12-inch piece with glue. Fit and bond the opposite end of the metal rod. The vertical uprights and the catapult bar are now complete.
-
8
Stand the uprights on a flat surface. Turn the trebuchet so that the downward sides of the outer triangle panels are facing you.
-
9
Lay one of the 10-inch pieces on its side. Fit one end flush against the bottom of the right-side 12-inch piece so that the 10-inch piece is pointing toward you. The pieces should form a letter "L." Bond the 10- and 12-inch pieces together with wood glue. Repeat for the left side.
-
10
Connect the free ends of the 10-inch pieces with a 3-inch piece by fitting the 3-inch piece between the 10-inch ends. Bond together with wood glue.
-
11
Form a roughly "U" shape with three additional 3-inch pieces on the opposite end of the 12-inch pieces. Bond all pieces together with wood glue. The trebuchet base is now complete.
-
12
Place the long sides of three 3-inch pieces side-by-side. Bond together with wood glue. Frame the 3-inch-by-6-inch piece with the two remaining 3-inch and 6-inch pieces. Bond together with wood glue. This will act as the glove for the pumpkin to sit in before being launched.
-
13
Center and bond the bottom of the glove to the long end of the 16-inch arm with wood glue.
-
14
Tilt the 16-inch arm back so that the short end is in the air. Tie the long end to the right side of a 12-inch upright with string to hold it in place.
-
15
Wrap a heavy object -- a steel Chinese ball or a wad of batteries -- securely with string and tape. Allow three inches of loose string to hang from the heavy object. Tape two inches of the loose string to the short end of the launch arm. Allow the heavy object to hang. Notice the tension in the string tying the arm to the upright.
-
16
Take the trebuchet outside and set on a firm, level surface. Place a miniature pumpkin in the glove. Cut the string tying the launch arm to the upright. Watch the weight drop and the pumpkin fly.
-
1
Tips & Warnings
Be sure to use the device at a safe distance from other people, automobiles, homes or animals.
