KN03 + Sucrose propellant

You will need: KN03 Sucrose Plastic container with lid Hotplate Wooden spatula Aluminium cooking pot This propellant is fairly easy to make, but there is a high risk factor if safety guidelines are not followed. To begin with, the sucrose (cane sugar) should be the powdered variety you find in the supermarket for putting the icing on cakes. The potassium nitrate should also be as finely powdered as possible. If neither can be obtained in powdered form then a kitchen blender is sufficient to do the job.

NOTE**- Never blend, grind, or powder ingredients while they are mixed, accidental combustion may occur with disastrous results.

If you are already familiar with this formula, I want you to forget everything you very heard about the ratios for mixing it. Once you have the two powders ready, mix them together about 50/50, put in a plastic container and shake well. Take a small sample of the powder, about 1 teaspoon, and place on the ground outside the house and light with a match. It should flare up with a lot of white smoke and leave residue behind. This next part is very important so read carefully. To get the ratio perfect, you must look at what has been left behind. If there is a lot of black crusty char left, there is too much sugar in the mix. Add more KN03. If there is hard white stuff, there is too much KN03. Add more sugar. Keep repeating this process until there is little or none of either left behind. What is happening here is you are evening up the mixture so that you can gain maximum gas output by the reaction. The less of your ingredients that are left behind, the more gas that will be expelled by the rocket motor. Now for the next step, melting. This is a very potentially dangerous part of the proceedings. This mixture is highly flammable as it stands and should be treated with care. Any flame or spark can ignite it so it must be kept away from heat sources, it is however not been reported to be shock sensitive. Before you melt, you will need to estimate how much you are going to need to use. I do not know exactly how it works out so if anyone knows what how much is needed for a specific engine size please notify me. Put all of it in the pot (this depends on how much you are making, it is not advisable to make more that 1kg at a time). You should be melting this outside, if it happened to go up while you were melting it there would be a disaster. I have seen this ignited in its molten state; it is about 10 times more volatile and burns with a very hot flame. Turn the hotplate on to a low heat; if your hotplate has a setting of 1-10, then it should be on about 3-4. The melting process may take up to half an hour if done properly. If a misguided individual did decided to heat this on a high heat or even on an open flame, it would burst into flames and burn them severely before they could even think about moving. Keep stirring it around the whole time that it is on the hotplate, and keep scraping the bottom clean as the fuel begins to melt. If the melting fuel on the bottom of the pot is brown and runny, then the heat is too high and you are at risk. The whole lot should eventually go light brown, but never let it go runny. You should keep it to the consistency of soft play dough. Once it is beginning to stick together, turn the hotplate down one notch. As it melts you should take the pot off the heat every 30 seconds or so and give it a good mix around, keeping in mind that you have never stopped scraping the bottom. This is very important to remember, if the fuel is left alone to melt it will eventually reach ignition temperature and you will be in big trouble. If at any point the mixture begins to smoke or give of unpleasant fumes (this fuel smells pleasant while melting), take it off immediately and sit it in a bucket of water. It should never go darker than a light brown, if it does then the heat is too high or your sugar is not fine enough. As the fuel turns brown, this means that the sugar is being oxidised, the browner it gets, the lower the performance of the rocket. Once the fuel is totally melted and bonded together and in the same consistency of play dough, take it off the heat and use your spatula to put it into your engine casing. It must be used immediately because as it goes hard as it cools. Once it is completely cool it can only be broken by throwing at the ground or hitting with a hammer. Your pot will also be left with hard fuel in it, to remove wait until it has cooled right down and bash the bottom of the pot on something hard. You can also remove the fuel by soaking it in water, it will dissolve. Your engine must be kept airtight until you use it and it is advisable to use it within a week, as the fuel is hygroscopic and absorbs water. Never throw a match into the pot to clean it out; the char that is left behind will contaminate the next mix and lower performance. A variation of the fuel can be made by adding sulphur to the mix, this will increase efficiency and performance. I have not used this method however, because while melting the sulphur emits sulphur dioxide gas, which is very potent and turns to acid when bonded with moisture. This is especially a hazard in the lungs. Follow these instructions carefully and nothing should go wrong. As always, general safety rules apply with handling pyrotechnic substances. If there is anyone who has anything to contribute or has any questions, please contact me:          THEJMAN@spyring.com

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