Brief:
This is a really tall rocket. The idea was to make a rocket long and thin with a minimum amount of effort. A really easy but impressive scratch built project.

Construction:
The rocket uses 2 stock BT-70 tubes as its core. You'll also need a BT-70 nosecone and a BT-70 tube coupler. For the motor mount, I used a 13 inch 29mm motor tube with 2 plywood centering rings. The fins require a sheet of 1/16 inch birch plywood. For recovery, about 36" length of both 100# Kevlar® thread and 1/2 inch shock cord along with a 24 inch rip stop nylon parachute.

This rocket is pretty easy to build. Mark the coupler at the halfway mark and then use CA (super glue) to attach the tube coupler to the forward tube at the mark. Don't glue the coupler to the rear tube at all. Use masking tape to get a nice secure fit. I used an Estes style shock cord mount to mount the Kevlar® about 5 inches into the lower body tube. The reason to do this is to allow the rocket to be flown with just the lower body tube or with both tubes together. Instead of white or wood glue, I used CA to make the shock cord mount.

Build the motor mount by using CA or 5 minute epoxy to attach the two centering rings about 1/2 inch from either end of the motor mount tube. Put a ring of epoxy 12 inches into the rear of the lower tube and then stick the motor mount about 6 inches into the tube. Put another ring of epoxy 1/4 inch into the rear of the lower body tube. Push the motor mount the rest of the way into the body tube and let the epoxy dry.

For the fins follow the RockSim file for a pattern. If you don't have RockSim: The root cord is 3 inches, tip cord is 1.5 inches, sweep angle is 45 degrees (to make it easy to miter), and semi-Span is 2 inches

It is easy to cut these fins with an electric miter saw. Cut the plywood into 2 inch lengths against the grain. Then stack three sheets together and cut a 45 degree angle.measure 3 inches on the root cord and 1.5 inches from the top of the 45 degree cut. You'll end up with about a 15 degree final cut. The fins can be surface mounted with epoxy. Put on some good fillets.

Run the shock cord through the upper body tube and tie on the elastic and nose cone. Attach the parachute about 1/3 down the elastic and put the components together.

Flight and Recovery:
For the first flight of this rocket, I used an AeroTech single use F20-4W. I simply used some masking tape to lock the motor in. A band around the motor base acts as a thrust ring and tape around the motor mount for retention. A 3x3" Nomex® blanket for wadding and off she went.

It was a beautiful slow launch followed by an arrow straight flight and a perfect parachute deployment. The only problem was that the rocket landed on concrete and took some minor damage to one of the three fins. A slightly larger chute might be appropriate for hard surface landings.

Summary:
PROs: It was fairly easy to build and looks very impressive both on and off the launch pad. At 10.5oz this rocket is flyable on an F motor with no FAA notice required.

CONs: Surface mounting of the fins requires some kind of bracing. It would have been better to cut slots for a "through the wall" fin arrangement. It would have added considerably to the difficulty though.

I wouldn't have attempted to build and launch this size of a rocket without the help of the simulation program. I was much more confident that it would be successful after running all the simulations and verifying that the CG was just about where the program predicted.