3D-Printed rocket disaster 

This rocket was made from 3D-printed parts, cardboard postal tube and a standard model rocket parachute and solid rocket motors.
Two F15-6 motors (the most powerful you can buy without a licence) were used in a cluster arrangement. On launch only one engine ignited, under powering the rocket; also the igniter cable on the 2nd unlit motor travelled up the launch rod with the rocket on launch (further reducing the active launch thrust).
Back to the drawing board...