You don’t need any of that chemical nonsense to just have fun, though, as this compressed air cannon from [OtisLiu153] demonstrates. The build uses PVC pipes for both the barrel and the air tank.

A turbulent air assist can make scorch marks worse, not better. 3D-printed nozzle to promote laminar air flow on the left, stock nozzle on the right. As an experiment to improve the quality of the ...