Instructions to Build a Rat Trap Racer

Making a Rat Trap Racer

• 1

  Drill holes in the two pieces of wood, one inch from either end, to hold the wheels and axles. Drill hole in the center of the rear axle so that the toothpick will fit snugly.

• 2

  Position the rat trap so that, when the trap is set, the wire of the trap faces to the rear of the racer. Fasten the two pieces of wood onto the trap, with nails or screws, so that the trap is centered along the wood pieces.

• 3

  Attach wheels and axles to the racer. Secure toothpick to the rear axle with wood glue. Cut the toothpick so that one end is flush with the axle and the other end of the toothpick extends 1/4 inch out of the axle.

• 4

  Tie a loop in the end of the string. While the trap is in the sprung position, measure the string so that the loop is almost touching the rear axle and the other end of the string reaches the crossbar of the trap. Tie the string securely to the crossbar of the trap.

• 5

  Set the trap. Place the loop of string over the toothpick, and wind the string onto the rear axle so that the string is winding over the top of the axle. To run the racer, place it on the ground and spring the trap. The motion of the trap will pull the string off the axle, propelling the car forward.