Catapult
thingiverse
I'm building a catapult for my drafting class and I'm hoping it will turn out well, but only time will tell - my teacher still needs to print it out before I can see the finished product and get her feedback.
Download Model from thingiverse
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.