[Richard] does say making larger rocket engines out of 2 or 3-inch PVC may not make much sense due to the increased chamber pressures. There is a fairly clever reinforcement method for these PVC ...

there’s more than enough info on his site to try and recreate some of his experiments, but perhaps you should start here instead: How to Design, Build and Test Small Liquid-Fuel Rocket Engines.

Join Dr. Larry de Quay of NASA as he explains the physics and chemical processes of rocket engines and some of the analytical methods used in their design. Discover the design approaches and ...

Will Edwards is the co-founder and CEO of Firehawk Aerospace, a hybrid rocket engine design and manufacturing firm. Firehawk’s rocket engines are powered by their patented 3D printed rocket fuel.