Recommended print settings:
Hard base should be at least 50% infill, 3 perimeters. They should be heavier than the top by at least 25 to 50% in order to fly true and have the flexible cap impact first.
Soft top:
2 perimeters, 0 infill. 3 to 5 top and bottom layers.
It does take a decent amount of force to shove the tops on.
Made some squishy topped bullets as my house has a lot of big windows in it.
Play with infill percentages and perimeter numbers to try and get the weight of the cap below the base, and change how squishy you want it.
I will post a better guide as I try different infills, layer heights, and perimeters.
All parts are orientated for ideal strength and printing of necessary overhangs.
Print the top section with 2 perimeters and zero infill for maximum squish. My TPU is 95 shore hardness so your mileage may vary with softer plastics like ninja flex.
Cap should just push down onto the base and make a whole rocket that's hopefully a little safer for windows and little ones.
The author remixed this model.