A group of us got together and built the worlds first pumkin ballista for Rowan's pumkin chunkin competition. The event was well setup with Monster energy drinks there, a live band, free food and t-shirts.
Rowan University Pumkin Chunkin 2009
The ballista was built using 2 leaf springs off of an f-150, and we designed and welded together a frame from mild steel bar stock. The springs were pulled back using a come-along, and fired with a quick release we built, modeled after a pelican hook. We calculated that when pulled back to firing position the springs were at about 1400 lbf.
Im the person in the video who cranks, fires, and shoulder stocks it.
We won first place and $100 to go to the bar!