a website for those who got back into model rocketry as adults
BORN AGAIN ROCKETEER home

homemade rocket

Let me start by saying this: No one should ever attempt to build his or her own rocket engine. It's much safer to use store-bought engines made by professionals. Having said that, it was one challenge I just could never resist. My first success in this area was in the form of a matchstick rocket: you wrap the head of a paper match with aluminum foil, leaving a tunnel out the back for exhaust. They work, and they are also relatively safe due to the small propellant mass. I also got the Teleflite instructions for building your own rocket motors when I was a kid, but I never managed to get one built.

As an adult, I returned to the task of homemade rocket construction, after reading the tantalizing account in the book, Rocket Boys. I built my first rocket using a small, thick-walled cardboard tube I found someplace. I made the rocket candy propellant described in the book, having gone online to find out the correct proportion of ingredients. The first rocket burned a long time, but it never left the ground. All it did was sit there and eat away at its fins and make a lot of nice red fire and gray smoke. Not enough thrust.

Candy propellant is supposed to generate twice the gas volume of black powder, but it burns a lot slower. The solution was a center-bored motor design. A little harder to make. Plus I rolled my own tube for this one. The rocket launched impressively into the sky and blew out its nozzle about twenty feet in the air. The rocket itself simply vanished. We found it later after an extensive search. It must have gone high.

Version three was a more advanced design, with a little less of a center-bore, and a slide-in propellant core that was supposed to prevent pressure build-up from cracking the propellant. (I got this idea from some web site. The outside of the propellant core is wrapped with paper so it can't burn. However, the combustion chamber pressure can distribute evenly around the core so it doesn't rupture.) This was the biggest of the three rockets. It was probably equivalent to a D or E sized engine. I painted this rocket lemon yellow to aid in recovery. It went really high, totally out of sight. It was incredible. Later we found it on the ground, intact except for a chip out of the hand-turned balsa nose cone. Success!

Now that I've built and flown my own rocket motor successfully, I don't have any burning desire to keep working on this potentially dangerous type of project. The big reward was just doing it and having it work. Some people make their own model rocket engines complete with delay and ejection charge, but I'm satistfied just to have built my own working rocket motor from scratch.