How to Build a Catapult That Can Throw a Pumpkin
Things You'll Need
- 1 15-foot thin spar
- 3 15-foot spars
- 3 8-foot spars
- 1 3 1/2-foot spar
- Double pulley
- Large empty coffee can
- 50-foot length of 1/4-inch rope
- 7 12-foot pieces of 1/4-inch rope
- 1 20-inch piece of 1/4-inch rope
Instructions
-
-
1
Lash together the three 8-foot spars using 12-foot sections of rope to form an "A"-shaped triangle with the cross-bar about 8 inches from the ground. .
-
2
Stand the triangle vertically. Lash two 15-foot spars approximately one-third of the way down each side from the top so they act as support legs for the triangle. Lash the third 15-foot spar to the cross-bar of the A-frame. Position all three spars behind the triangle.
-
3
Construct the throwing arm using the thin 15-foot spar and the 3 1/2 foot spar. Lash these two together to form a lower-case "t". Place the shorter spare approximately 3 feet from the thicker end of the thick spar. Attach the large coffee can to the thinner end of the thick spar with a length of rope.
-
4
Place the throwing arm on the triangular frame. Lash the short spar top of the 15-foot support legs loosely so the short spar can rotate freely.
-
5
Attach the double pulley to the center of the triangle's cross-bar with the 20-inch piece of ropes.
-
6
Tie the middle of the 50-foot rope to the thick end of the throwing arm and run the two ends of the rope through the the double pulley and out on either side of the catapult.
-
7
Assign several people to pull the launching ropes. When the projectile has been loaded and everyone is safely clear of the throwing arm, the designated firing control person can shout "fire" and order the launching ropes pulled. The firing-control person who stands at the front of the catapult should manage the descent of the throwing arm.
-
1
sports