2. Building

We got the wooden chassis from Zhi En's father's workshop, and we cut the mousetrap using a straight snip scissors.After that, we drilled a hole through the mousetrap and wood, and bolted them on tightly.Then, we used bubble tea straws to hold the pencil axle in place, and attached the pencil through the CDs, using the bottle caps to prevent it from swaying about.We attached a lever arm to the mouse trap and tied a length of twine around the lever arm to pull the axle.We also tied a cable tie to the axle and cut the loose ends off in order to let the twine let go of the axle after being pulled all the way, to allow the axle to spin even after all the twine has been pulled.