A 3D-printable model of the Delta IV Heavy rocket developed by ULA and Boeingthe model is full scale but designed to be sclaed down for printing - it is recommended to be printed in 1/300 scale or larger since the connections between the core and boosters become rather tiny if you go smaller and might be difficult for average nozzle size printersstruts and engine bells were thickened to make them printable when scaled down