catapult
cults3d
To build catapults you will still need a meter of cord I prepared a video about how to insert cord. It is a bit tricky but it does not cause trouble. By changing the cord tension you can adjusted catapult power.
Download Model from cults3d
With this file you will be able to print catapult with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on catapult.