Introduction: ENG 317 Knex

In this project, we are using K’Nex to build a catapult. Our team members are Emily Brown, Jiajun Luo, and Grant Rothweiler. Our principal investigator and instructor is Rebecca Ruggiero. Our team estimates the duration of this project is roughly fifteen minutes. Building this catapult is not only fun but it also can be used for shooting materials across the room. We hope that while building the catapult our audience gains a sense of knowledge and capability with K’Nex pieces.

Step 1: Part List

  • Part List:

  • 8 Blue rods

  • 7 White rods

  • 2 Green rods

  • 2 Blue circles

  • 2 Yellow rods

  • 2 Red rods

  • 5 Purple clips

  • 4 Orange connectors

  • 1 White connector

  • 12 Gray connectors

  • 1 Green connector

  • 2 Blue connectors

  • 2 Black rod caps

  • 3 Wheels

  • 1 Elastic band

Step 2: The Base

Snap 4 white rods into 1 white connector

Step 3: Side Supports

Snap 3 gray connectors onto 2 blue rods. Diagonally snap 1 yellow rod into 2 gray connectors. (do this twice). Slide 2 more gray connectors into all gray connectors.

Step 4: Base

Connect white connector base into Base 1 and Base 2

Step 5: Part D

Slide purple clip into the middle of a white rod. Snap white rod ends into 2 orange connectors (repeat twice). Connect each clip to the other white rod.

Step 6: Throwing Arm Base

3 purple clips slide into 1 blue rod. Connect to the top of part D (opposite of structure).

Step 7: Top of Throwing Arm

Clip white rod into green connector and clip to opposite side of step D.

Step 8: Throwing Arm Base

Slide blue rod through ends of part D. Place circles on the end of a blue rod.

Step 9: Blue Support Rod

Connect blue rod to the top of gray connectors.

Step 10: Green Rods

Connect 2 green rods to the top of the base supports.

Step 11: Rubber Band

Wrap elastic band around 2 green rods and loop behind part D.

Step 12: Wheels

Slide 2 wheels onto the red rod at the front of the structure. Place the black rod cap at the ends of the red rod. Slide big wheel onto the remaining red rod and snap it onto the back of the structure.

Step 13: Ammo

Connect two blue connectors together and place on green connector at top of throwing arm.