RIM-67A Model Rocket

thingiverse

This is a model rocket of a RIM-67A missile, designed to be launched with a C or D motor (18 mm). The scale is not perfect due to the need for larger fins, but it looks remarkably like the real thing. I have designed the fins and rocket base to be 3D printed for optimal results. To minimize weight, the tube and nose cone are made of cardboard and lightweight plastic from Estes kits. The parts were designed using Sketchup and then converted to STL format. I simulated the rocket with OpenRocket, which estimated a stability level of 3.21 cals, making it suitable for this model. Build Materials: * 4 middle fins (plastic, printable) * 4 stern fins (plastic, printable) * 1 rocket base (plastic, printable) * 1 Estes BT-55 tube (cardboard) * 1 Estes BT-55 nose cone (lightweight plastic) Printing Parameters: I used an XYZPrinting Da Vinci Jr 1.0 printer with XYZPrinting white PLA. The general printing settings were: * No support material or build plate adhesion required * Standard speed * Extruder temperature: 210-215 degrees Specific Printing Settings for Fins: * Solid printing (100% infill) * Layer height: 0.1 mm Specific Printing Settings for Rocket Base: * Infill density: 10% * Layer height: 0.3 mm Building the Model: Cut a BT-55 tube to 320 mm in length and create four recesses, each 1x180 mm, at 10 mm from the base of the tube. Insert the middle fins from the inside out into the tube and glue them in place. The coupler between the rocket base and the tube may require sanding for a smooth fit. Plug and glue the tube into the coupler. Insert the stern fins into the recesses of the rocket base, securing them with excess glue if necessary. You can print a single fin and adjust the thickness accordingly. Prepare a parachute and attach it to the model. Insert the BT-55 nose cone, linking it to the parachute and tube with an elastic band. Glue a 50 mm plastic tube for launching at 130 mm from the bottom of the rocket. Launching the Rocket: I have only tested a full cardboard version of this model, which requires precise fin alignment. I recommend starting with a C motor (C6-7) and progressing to a more powerful D motor (D9-7) upon success. The 18 mm rocket motor should fit snugly into the motor case, secured with duck tape if necessary. The motor must be firmly seated in the case for proper expulsion charge operation and parachute deployment. The motor case is designed to allow easy removal of the motor after flight. Simulations indicate that the rocket could reach a height of 337 m with a single D9-7 motor.