It doesn’t have to be hard to build a model rocket engine. You don’t have to look up all the specs, dwell on the power you need, and worry about purchase costs. You can make your own model rocket engine with things you probably have around the house (and one key ingredient you may not). Here’s how to make a simple sugar engine for your rocket.
1. Make a cement paste out of cat litter.
You need to create a plug that will contain the reaction, and the cheapest way to do this is using cat litter. Grind up 0.25 cups of unscented cat litter until it’s a powder. Add in water a little bit at a time until you’ve formed a thick paste. Put a dowel into your model rocket, but leave a gap at the end and pack in the paste.
2. Mix your rocket fuel.
Now comes the fun (and dangerous) part. You’ll need potassium nitrate (KNO3) and powdered sugar. Potassium nitrate can be ordered online or found as stump remover at home improvement stores. Take a plastic container and add in 14 grams of potassium nitrate. Next, add 7 grams of powdered sugar. You’re making rocket fuel, so handle the ingredients with care, as they are combustible. Mix them well, but carefully. You can shake them, but very gently, and it has to be for an hour.
3. Pack and prepare your rocket.
Pack your fuel into your rocket on top of the cement you made. Add fuel until there is about 3/8ths of an inch of tubing left. Insert a 6D nail gently so that it creates a hole through the fuel and cement. Add more cement on top of the fuel, then create another hole through that cement connecting to the first. This is the hold you will use to insert your fuse. Ensure that your fuse is long enough to give you plenty of time to get out of the way. That’s it! You now have a rocket engine ready to go.