Flying model rocket for use with A, B, or C size engines. C are probably the best although I'm out of them at the time of this post so I flew the test flight with a B6-4 and the chute deployed just in time.

I may post further designs later, but as I printed it is does fly stable. All the parts are designed to print without supports or infill to make them light weight. They do print best with Simplify3D as it allows multiple printing profiles to print a single part.

Here is a video of the test flight. https://youtu.be/Sk4pJ7XX45k

Update: I just added a nose cone that has a thicker base to help move the center of gravity forward on the rocket. I also added a tube extension that will also help move the center of gravity more towards the nose. I've added my initial tail design that might now have a stable flight if used with the tube extension and the heavier nose, it may also work with multiple tube extensions and a much longer rocket. And lastly I have changed the launch guide in the tail section to reduce the contact area with the guide rod. I have not tested any of these parts so leave a comment if they work for you. Also leave a comment if there is something else you would like to see.