At the end of senior year of highschool I started on a reusable rocket engine to test solid rocket propellant and the effect of different nozzle shapes on thrust. I CNC’d out the plates and then manual lathed out the pipe, then finally I welded the end cap to the pipe, but left the nozzle piece as a modular portion that could be bolted on. The last piece was the nozzle, but I never ended up following through with it as I graduated a few days later.
