The GRAPHICA Powerball is a quick-printing .STL 3D model of a working catapult with a ball that you load and launch.
Use it to test your 3D printer's ability to print mechanical moving parts. The catapult mechanism prints in one piece. If your print bridges, you can calibrate your printer before getting into a longer print, saving time and filament.
This model is great for demos because of its playful design and quick print time. All the GRAPHICA models are .STL files, and most print in less than an hour.
Difficulty level: 2 out of 5. Also comes with a display base.