A working trebuchet

you may want to scale down the trebuchet in the slicer as it will be to big to fit. You mat also want to scale down the axle more as it has no tolerences designed for a 1 kg counter weight and a 7.5g projectiles simulations show that it should fire 15 to 25 m (precise distance was 22 m) sling should be as ling as the end of the long part of the arm to the pivot point.

can also be made of wood