Picture of K'nex catapult (the orange arch)
This is a simple 10 minute catapult that I built using the 521 piece K'NEX set. Using a strong rubber band I have been able to fire a marble about 20 feet.

Step 1: Parts list

Picture of Parts list
Here's a parts list.

4 red rods
3 yellow rods
3 bendable orange rods
2 white rods
11 green rods

6 grey 45 degree connectors
6 red 90 degree connectors
4 green 135 degree connector
4 orange connectors
2 grey sliding connectors
2 blue sliding connectors
2 purple clips
2 tan connector clips
2 back rod clips
1 small gear
singhjr96 (author)  sandroknexmaster2 years ago
Hope it's good enough to win a prize in the contest.
Don't misunderstand me, but I think this will not win a price. It's not very innovative,
and almost everyone could build this.
But no offense I like it anyway! :)