Composite Rockets

Rocket Design The rocket should be designed and tested in a rocket simulation software. Rocket should then be modeled in Autodesk Inventor. – All components should be created as part files and then assembled. – Create drawing files for each component and the assembly.

Components Nosecone – print on 3D printer Payload – composite materials Nose Block/Transition – 3D printer Body tube - composite materials Recovery – streamer or parachute Launch Lug – piece of a drinking straw Fins - composite materials Engine mount - from engine kit NOSE BLOCK/ TRANSITION

3D Printer Parts Nose Cone & Nose Block/ Transition  Either design the parts as solid parts in Inventor and print them as a sparse fill or hollow parts with one open end if your printer has the soluble support.  A small eye screw can be used to attach the shock cord to the nosecone or transition.

Rocket Body Form Choose a dowel to use as a form for the rocket body tube. Sand the dowel to remove any rough spots. Wax the dowel with a paste wax.

Dowel Preparation Wrap the dowel in a thin layer of aluminum foil so the resin does not stick. There should be no wrinkles in the foil so there is no where for excess resin to build up and add weight to the rocket. Notice the Inventor drawings in the background

Measure out the proper length of fiberglass tape by wrapping it around the dowel at an angle so it creates a tube that is 2 inches longer than the body tube designed. The tape should overlap when being wrapped, 1 or 2 cm. The extra length will be trimmed off after the resin dries in order to create clean edges. The payload section can be created with the same procedure.

Combine the matrix with the reinforcement using the techniques you learned creating your composite materials test samples.

Wrap the wet tape around the foil covered dowel, make sure to not have any wrinkles or bubbles. Then use a piece of 4 mil plastic sheeting to wrap around the composite material. Again any wrinkles or seams will give a space for resin to gather and add weight to the rocket.

Use cling wrap to compress the excess resin from the form. Wrap it tightly around the form on the outside of the 4 mil plastic. Let dry over night.

Finishing the Body Tube De-mold the body tube by unwrapping the cling wrap, and plastic sheeting. Push the wooden dowel out through the composite body tube. Trim the tube to the proper lengths using a small coping saw. Peal the aluminum foil from the interior part of the tube. The original wooden dowel or a round wood rasp can be used to scrape out the foil. Don’t worry if you do not get it all out, foil is used because it will not burn.

Fins Make a 2 or 3 layer composite plank much like the ones made for composite testing samples. Then mark out the fins on the dried composite planks the same way you would on a piece of balsa. Cut the fins out using scissors or the small coping saw.

Purchased Parts The engine mount, parachute, and shock cord can be purchased from a rocket supply store or they can be made from materials you have on hand.

Assembly When assembling the rocket super glue can be used to tack the components in place. Mix up some resin and use a small brush to permanently adhere the components to the rocket. Let dry and then Fly.