Simple model rocket to fly with my son's Estes models. I lost every rocket design I printed before and didn't like the motor retention methods on other models so I sat down and made this. It has a quick mount for the motor and plenty of room for a parachute and wadding. Can work with Class C or D model rocket engines from Estes. Just print the appropriate type motor and block parts. Will post an update after launching this rocket. Also working on an Army Men delivery system...I made mine with the minimal parts which was about 18 inches high. You can add mid-sections to make it longer but I don't know at what point that would be unstable. The basic assembly requires: One of each part except: Assembly: Dry fit all parts first. Some sanding/razor work might be in order depending on your printer. Place a rocket engine into the Motor Type C/D and insert into the Rocket Base. Slide the Motor Block with the tapered side down into the tube of the rocket base until it firmly holds the engine centered in the tube. Apply a glue to the block to hold it in place. I use a liquid Acrylic glue applied with a needle. Slide the fins into the guides on the rocket base section and glue them in place. Glue a tie-down insert into the top the rocket base. Then add and glue the extension/payload section. Then glue another tie-down and secure a shock cord to the tiedown that is at least three times the length of this section (or 300mm). Then glue down the next extension/payload section with the shock cord going through the center. Refer to photos...