Creating and Testing my own Rocket Motors

This blog is a step-by-step walk-through of the process I use to make my own rocket motors. If you're interested in the design/test process of the motor, check out this page. The  motor that I build here is the same as I usually make, except it has one difference - it has a plastic piece attached to the outside so that it can be put into my 3D printed rocket. This motor uses dry fuel; I am working on making one that uses liquid fuel, which should work even better than this one.

Step 1. I cut out the case for the motor from a long pvc pipe:

Step 2. I marked the screw holes on the sides of the caps, and the nozzle hole on the top of one of the caps. The nozzle is where the blast of the motor will come from:

Here are the three different drill bits I used; the largest one is for the nozzle, and the two smaller ones are for the two types of screws:

Step 3. I drilled all of the holes, screwed on the cap with the nozzle, and attached the plastic piece onto the case:

Step 4. I made the fuel for the rocket motor. It is 65% potassium nitrate, and 35% powdered sugar. I then mixed and sifted it:

Step 5. I poured and packed the fuel into the motor:

Step 6. I screwed the back cap onto the motor:

Step 7. I took the motor off of the rod, and it is done! Now it can be placed into the rocket for use.

Step 8. I made an igniter for this motor using a matchstick and two copper wires:

Here is the motor in action. It is astonishing how powerful it is:

When I began trying to make my own rocket motor, I did not think it would end up being so difficult. Here I'll discuss the design, each test, and the improvements made. This motor is a PVC pipe packed with a fuel mixture of 65% potassium nitrate and 35% powdered sugar. Besides for that basic idea, the rest haad to be figured out with the experiments below.

Tests 1-3: In the first three tests, I had no end caps on the motor and experimented with clay and other materials to contain the pressure. I also experimented with putting an ejection charge into the motor, but that also didn't work. Regardless, all three first tests looked very similar to the video below, with the fuel breaking through any barriers and producing a lot of smoke, but virtually no power as there was no build-up of pressure inside the motor:

Test 4: For this test, I tried to make a cap using some metal that I cut and shaped. However, there were gaps, and so the flame was able to escape through these gaps, which set the entire motor on fire, as seen in the video and picture below:

Test 5: This was the first successful test, as I figured out that I could put PVC caps onto the PVC pipe. These caps leave no gaps and perfectly contain the pressure. You can see and hear how powerful this motor is: