This rocket has been optimized to fit onto 1/2" pvc. The inner diameter is 21.8mm. This is a snug, smooth fit. If the first layer mushes, the bottom lip may need to be sanded a little to get the fit just right. A test fit stl has been included. I suggest printing it to make sure the rocket will fit onto your tube. Scale the x/y coordinates accordingly if needed.

I designed the rocket aerodynamics using openrocket. The nose cone isn't perfectly optimized because the blunt nose wasn't as appealing. The performance loss is quite small. The most important factor is making the body smooth.

I am including an additional file with a smaller rocket for those with smaller print volumes or don't want a rocket that goes so fast and high. It has the same internal dimensions and nosecone, but has smaller fins and is 170mm tall.

Do not launch these at people, animals, or anything that you wouldn't want to break. The exit velocity is over 80mph and can top 130mph with higher pressures.

Here's a video of it in action. https://youtu.be/ItQ21whXjjk
Here's a video of how I built the launcher: https://youtu.be/HnobReve_yg

I'll be uploading a different version with swappable nosecones for anyone who wants to make this into a science experiment. Also be on the lookout for a version that can hold a small altimeter.