Golf-catapult physics experiment

I made this catapult for mine and my former classmates final examination-project during high-school. The goal was to compare the theoretical physics we had learned to practical physics.

Additional parts needed:
- 100mm long 8mm diameter steel rod (ebay or similar)
- A pair of skateboard bearings

The catapult itself is printed in PLA (white) and Colorfabb-XT (grey) for the more stressed parts. The projectile intended is a golfball and the "slider" supports a resolution och 0.5 degrees. The steps are 1 degree but since the "stop" extrudes a bit at one end 0.5 degrees resolution can be achieved by turning it. For a weight we used a 1kg iron weight though I provided a hole for attaching smaller, freely hanging weights. We also tried with 2kg weight which resulted in the need for the repair-parts. I put mine together using superglue. LOTS of superglue. Don't forget to print the "-x2" parts twice!

For the full report we wrote, in swedish (sorry), click this link: https://drive.goo