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First, a disclaimer: this is not a set of instructions, nor do I recommend trying what I'm about to tell you. This blog entry is about a project I completed a number of years ago. It was dangerous then and is still dangerous now. In short, don't try this at home.
Now for the good stuff . . . 
Back when I was a wee lad, I did what many youngsters do and made model rockets. I loved to glue on the fins and paint my creations..My parents would then buy engines which I added to my rockets. I loved how these rockets would fly into the sky with a wonderful whoosh sound. As I got older, I became curious about how those little rocket engines worked. One day, I found an advertisement in a popular science magazine for directions on how to build 5-cent sugar rockets. I sent away for the information and followed the instructions. Today, you can find online for free the directions that I purchased.
One of the chemicals I used was hard to come by, but my father ordered it for me. I managed to get some of these rockets off the ground, but the results weren't very exciting, and the engines never worked well. I put the project aside, but I always knew that it could be better. Sometime after I graduated from college and began working as an engineer, I happened upon this website and just knew I had to try again. Back in my younger days , I mixed up something similar to the rocket fuel described, but with the purpose of making a smoke bomb. This design uses parts that you can find in almost any hardware store. If you know what you're looking for, you can even buy all of the chemicals right off the shelf.
Hey, refer back to my disclaimer before you get any wild ideas! Now back to the story.
 Armed with the right design, I began building the tools I needed to cast the rocket fuel and make the engine casing. First, let's talk about the fuel. The idea is simple. First, you mix the fuel over a heat source to create a sticky goo. You then spoon it into a paper-lined mold, ram through a rod to make a hole in the center, and let it cool. The mold is just a piece of PVC tube with a special base, and a top with holes in the center so the ram-rod can be pushed through. Centering the holes is very important.
The rocket fuel consists of just two things: an oxidizer, and sugar as the fuel.  Although regular sugar (sucrose) will burn, the fuel grain tends to be brittle and can crack. In addition, brittle sucrose caramelizes and burns at a lower temperature, which makes the fuel harder to work with and more likely to ignite while you're making it. The web site I used recommends a sugar called sorbitol, but I had trouble getting it. I found fructose in my local supermarket, however, so I decided to give it a try. Fructose has worked well for me and was used in the rocket in this video I shot, but I haven't seen it in the store lately.
Editor's Note: Come back tomorrow for Part 2!
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Re: Solid Fuel Model Rocket Engines – Part 1
