To add to my collection of Flying Lego Rockets, I flew my Lego Technic "Death Star Booster Rocket" on an Estes C6-5 model rocket motor today. It flew to ~300 feet (~90 meters) before the ejection charge popped off the Lego Death Star "11x11 Hemisphere" 98114 + 98115 (from the current Lego 9676 set). The rocket consists of only 36 Lego pieces (no gluing). Eight 2780 "Technic Pins with Friction" hold the 64782 "Technic Panel Plate" Box Fin assembly together. Using 8 more "Technic Pins with Friction", four 32278 1x15 Technic Liftarms clip onto the gray 32324 "4x4 Technic Brick with Open Center" (placed upside-down to accommodate the black 3709b "2x4 Technic Plate with 3 Holes"). The Death Star hemispheres have studs on the top and bottom to press onto the Technic Plate.
I had to carve the cardboard rocket motor casing with a knife a bit, to enable it to fit inside the "4x4 Technic Brick with Open Center". Remove just enough (about 1/4") on four sides of the top of the motor casing, to make a square-sided shape that is fairly loose. You want the motor's ejection charge to deploy the Death Star (via the holes in the Technic Plate) AND push itself off of the rocket frame at apogee. The motor hangs down; make sure it is aligned well for straight thrust.
The black rocket frame and Death Star both impacted the earth hard , but everything just pops together for more flights! Nothing was cracked or broken. You can remove the minor black soot on the Death Star and Technic Plate by using White Vinegar.
The rocket can also fly on an 18mm C6-3 motor (with a 3-second delay). Holes in the edge of the 5x11 Technic Panel Plates allow you to place the rocket on a standard 1/8" launch rod (as shown in the picture).
I know that Blakbird is a model rocketeer -- are there any others who have flown rockets AND are Lego fans too? My SPokane Area Rocket Club (SPARC) NAR Section 626 buddies like to see unusual "Odd Rocs" like this.
@ Alasdair Ryan: I want you to note that I made my OWN MOC!
Edited by DLuders, 16 April 2012 - 02:14 PM.