Created
04/21/06

Related Items
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Materials
Stump remover
Table sugar
Red cement color dust
Stovetop
Fuses (from bottle rockets)

My roommate and I occasionally try our hand at making a homemade solid rocket fuel that is easy to make, safe, and stable. So far we have yet to get all three traits. Recently I ran across some old photos of one of our earliest attempts. I have no recorded data from this night, but it appears we were making sugar-nitrate fuel. This looks to be from before I tried powdering the ingredients and mixing with water to form a paste which could then be dried into a desired shape - these photos suggest we were still melting the components together (very carefully on an electric stove).

The ingredients are stump remover (mostly pure KNO3), table sugar (sucrose), and a small quantity of red cement coloring dust. The latter contains a lot of iron (II?) oxide, which acts as a catalyst. We discovered that this particular cement colorant behaved as an excellent catalyst, significantly improving burn rates. If I remember correctly, roommate suspected the manganese oxide in the dust was also acting as a catalyst.

Lab assistant.

Pictured below are three pieces of prospective fuel. The first is an attempt at forming a decent core grain in the proper shape for putting in a rocket. It crumbled while solidifying, and had issues with trapped air bubbles. The next image is just a ball of the stuff with a fuse shoved in it. The third image shows an attempt to test the propulsive aspects of our product. It looks kind of like a cherry bomb, but it neither did nor was meant to explode - it was supposed to scoot around on the ground for a couple seconds. It didn't. It just sat there. The containment envelope is polymer clay (like 'fimo' art clay). The last image shows a material we called 'bread' - I used mainly flour and a only a little bit of sugar to see what would happen. I even baked it in the oven like bread. The result was hard and, well, bread-ish. It did not burn fast enough to make a propellant, but it did burn.

Here is a sequence of three photos showing a lump of the material igniting on an elevated board, and a pic of one burning on our old cement patio.

Had we been successful in making a safe, stable, and powerful propellant, we might have eventually flight-tested our rocket engines:

Unfortunately, this formulation is quite hygroscopic, so it is unsuitable for use more than a day or so after it is made. We scrapped it.