My friend and I have been trying to synthesize rocket fuel. The next step in making our own rocket is integration into a body. After some research, bentonite clay seemed like a good nozzle material.

Erosion resistance looked promising:

After firing. Little nozzle erosion

We tried three static fires. All of them worked well with the bentonite, so we loaded up a full rocket motor and integrated it into a rocket.

Integrated rocket

The nozzle blew out on the pad. Apogee: 3”. I think it is because we were unable to consistently press the bentonite into the PVC motor tube.

Apogee