Summary

This is my modification of the Roman Ballista. I made a few changes.

1. Modified the trigger so it will go all the way down.
2. Modified the projectile so I can use bamboo sticks.
3. I kept breaking the pegs on the power lock so I changed it. This one uses a metal peg. To twist the string, I put a small peg in each area then used the wrench to tighten the peg. Once as tight as I wanted I pulled out the smaller pegs. I used low-tack tape to hold the power locks and small pegs together while tightening.
   pegs can be found here.
   https://www.amazon.com/gp/product/B07HLGVF8T

The black is HATCHBOX Sparkle PLA 3D Printer Filament, Dimensional Accuracy +/- 0.03 mm, 1 kg Spool, 1.75 mm, Black

The copper Silk Copper 3D Printer Filament PLA 1.75 mm 1 KG (2.2 LBS) Shine Silky Shiny Copper Like PLA CC3D ZHUOPU

Original with other files. https://www.thingiverse.com/thing:3498574