Helios 3: Homemade Rocket Candy Powered Rocket





Introduction: Helios 3: Homemade Rocket Candy Powered Rocket

About: I like to make things that move, sense, calculate, compute, blink, and make noise. I like making things that create high voltages, electrical arcs, and can light fluorescent bulbs at a distance. I like to d...

This is Helios 3. It is a 1/2 inch diameter by 18 inch long steel tube with an end cap, fins and an end cap with a hole drilled out.  It is powered by 30 grams of Rocket Candy (Sugar, Potassium Nitrate, and Corn Syrup.) This is the third rocket I've built. The first one was a copper tube that exploded on the launch pad, and the second can be seen here.  I have learned a lot since Helios 2 which includes better ways to make the fuel, more on the physics of fins, and most importantly, how to make it go higher! I did mess up when building the rocket so it will never fly straight again. When I was cutting notches in the tube to put the fins in, I accidentally cut the whole way through on the one fin. The pressure blew it out in the first launch, and by the last launch it was spiraling out of control severely.

Rocket Candy:
65% KNO3 (potassium nitrate, saltpeter, stump remover, fertilizer) - about 4 parts by mass
17.5% Sugar - about 1 part by mass
17.5% Karo Syrup (light corn syrup) - about 1 part by mass
I just use the ratio:



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    What does the corn syrup do that makes it do better then just sugar and potassium?

    6 replies

    Hey, is it possible to make a rocket with a paper tube filled with beutane ?

    Butane is a pressurized gas, putting it in a paper tube is like trying to carry water in a colander; it's not gonna happen, cap'n. In fact, butane is horrible for rockets, and so is propane if you don't build a steel cask to hold it. Solid fuel is all you want, it's so cheap and abundant. Paper shmaper, liquid anything isn't going in there.
    In short: no.

    It has nothing to do with the performance. Just potassium nitrate and sugar probably gives a more energetic fuel, but the con syrup gives it a better consistency when it is cooking. Without it the fuel becomes very brittle and it can't be molded. This is a problem because then it can't be formed and packed into a rocket. The corn syrup, however, is liquid even at room temperature. When the fuel is drying it stays pliable and can be shaped really easily. Then when it cools it becomes hard.

    oh ok. i never heard of using corn syrup in the mixture so i just wanted to know what it did.

    Well, I learned how to make it differently than how its normally made. Usually you heat up the potassium and sugar till the sugar melts, but i learned to dissolve everything it water then cook the water out.

    From what i've read online, this gives a higher performance fuel because there is less crystallization. And believe me, there is! I can get pure white fuel with the method i use, but the traditional fuel usually ends up yellowish brown at the very least.

    No offense to you, but you are partially wrong about the corn syrup. While it does make it less crumbly, the corn syrup contains glucose. This is mixed in with the table sugar (sucrose) essentially making it a dual propellant mixture. That's not to say it is bad, but it definitely does affect the final outcome.

    what is the ratio if using water? how long do you cook it, and how do you know when it is ready