Method/Procedure (steps to building the trebuchet)
The early trials/procedures were not effective and there were many sources of error. One problem was the sling which did not turn out to our desired look, and the length our original sling which controlled the centripetal acceleration. If the string was to short there would be too much acceleration therefore the ball would not slip out of its cradle at the desired angle. Therefore we decide to change the sling to a string attach to the tennis ball looped around a nail which was attached to the top of the arm. The original arm was not long enough to provide the necessary force required to fire the ball 15 meters. Therefore we shortened our arm from 2 meters to 1.80 meters.
Before building the trebuchet you will need to:
1) Cut two 2 meters long 2 x 4 planks of wood (length wise of the base)
2) Cut two 1 meter long 2 x 4 planks of wood (width wise of the base)
3) Cut one 1.8 meters long 2 x 4 planks of wood (for the arm). Drill a hole 1.1 meters away from the top of the arm.
4) Cut two pieces of 1.09 meters long 2 x 4 planks of wood for the vertical arm mount. Drill a hole on the side of the wood (a place for the axel).
5) Cut two pieces of 1.69 meters long 2 x 4 planks of wood, as a support for the vertical arm mount.
6) Cut two pieces of 0.89 meters long 2 x 4 planks of wood, as a support for the short side of vertical arm mount.
7) Lastly for supports, cut four pieces of 0.37 meters of 1 x 2 planks of wood (basically a 2 x 4 cut in half) and a 1.8 meters long 2 x 4 planks of wood for the bottom (a ball holder).
8) Now you’re ready to build.
Building Instructions/Assembly
1) Place the two 2 meters and the two 1 meter pieces together in a rectangular shape. Assemble them by putting four screws on each side.
2) Place the vertical arm mount 0.66 meters away from the 2 meter length side of the base. Form a 90 degree angle.
3) Attach the two long supports and the two short supports to the vertical arm mount.
4) Place the arm into the long steel bar, place a nail in the (very top) long side of the arm, and put the arm and the steel bar in between the vertical arm mount.
5) Attach the 1.6 meters pieces of wood to the vertical arm mount. After add all four 0.32 1 x 2 pieces of wood to the vertical arm mount.
6) Connect the tennis ball to a 1 meter long string. Make a loop on the top side of the string, and place this sling on the nail.
7) Place the ball on the middle of the horizontal support which is attached to the vertical arm mount.
8) Have a count down.
9) Release the arm = FIRE
Trebuchet Info