String Shooter

Little one in the loop

A string shooter is a cool physics toy. I was inspired by this great demonstration video by Bruce Yeany, and it turns out they can also be made LARGE with rope! – Zoro Feigl

Minimum viable prototype

This was my first minimum viable prototype 2 cable ties, a packer made of scrap paper. and 2 3D printed wheels wrapped in tape.

Here is a slow mo video of the Mark 1 working. It does work, but when it when wrong, it would rapidly tangle up a big knot around those wheels.

Mark 2 adding a trumpet to guide the string into 2 toothed wheels and 3D printed housing, Cad 3D Modelling in Solidworks – my CAD tool of choice 🙂 Here’s me playing with Keyshot rendering.

The Mark 2 worked well, but with heavier string, those 3V motors were underpowered, even when I ran them at 6v!

Parts ready to 3D print

Here are the parts plated up ready for printing on a Prusa i3.

The latest iteration is the Mark 3, it has bigger motors and a better trumpet, here it is working, each iteration is more reliable than the previous.

This project is on pause at the moment, the next stage will be to understand the variables; String weight, Power/torque/speed and to keep progressing the reliability. Then I have a Kinetic art idea for this to explore…