This plane flies good if tuned well, but cannot be hand launched easily. A better derivative can be found at thing 28266, here:
Known working instructions:
Print the wings and fuselage halves using ABS. .30 layer height (or close) , 2 perimeters, and 2 solid layers, .30 line fill. use a 0 degree angle for the solid fill on the wing, or you will have warping problems. Print the launcher with the same layers, but with 3 perimeters, 2 solid layers, and .35 line fill. Assemble the two halves onto the wing from each side, with the smooth side up. Use super glue to stick the halves together when you are satisfied that the airplane is symmetrical and that the wings are perpendicular to the fuselage. Put on a nice strong rubber band, and fly!
The control surfaces can be cut free to change the flight charateristics, and a small hole is provided to accomodate wrapping copper wire or solder for weight. 2" of 1mm solder seemed about right. Other materials and layer heights may work as well, please post your results!