Modular 3D-Printed Air Rockets

thingiverse

A previous design posting (thing:6409667) described how to construct and launch air rockets using 0.5 mm wall-thickness plastic body tubes and equipment available from Air Rocket Works, LLC (https://sites.google.com/view/air-rocket-works-llc/home).This posting uses the same launch equipment but adopts a modular approach to air rocket fabrication by using interchangeable 3D-printed parts for the body and fins and either soft foam or 3D-printed nosecones.As shown in the accompanying photos, the nosecones, body tubes, and fins may be batch printed 9 at a time in a 3 x 3 array on print beds with an area of 200 mm x 200 mm. Excellent quality and interchangeability have been achieved using a layer thickness of 0.3 mm at a print speed of 80 mm/sec.Alternatively, the file rocket_parts.stl may be used to print one or more groups of parts at the same time. The rectangle surrounding the grouped parts assures that after downloading they are oriented perpendicular to the surface of the print bed, ready for printing.The fins and nosecones are manually secured to the 3D-printed body tube using a 0.94-inch wide strip of green Frog tape wrapped on each end of the body tube to achieve a tight friction fit: https://youtube.com/shorts/qyT9q1N6xkc. Depending on print tolerances, the tape may need to be applied with up to 1¼ turns to ensure that the fins and nosecone stay in place during launch and subsequent impact with the ground. Note that infill density should be set at 100% to ensure maximum strength of the thin-walled parts (body and fins) but the 3D-printed nose cones may be printed with infill from 0-100% to vary their weight.Batch printing a functionally complete set of rocket components for use by schools or grade levels that may not have immediate access to 3D printing capability assures maximum participation by students.For example, a kit containing the following parts would be able to support a group of 18 students:9 short rocket tubes9 tall rocket tubes9 blunt nose cones9 pointed nose cones9 foam nose cones9 3-fin units9 4-fin units1 roll of green tape