Steps required to bring the models to 3d printers:
 1) create a model (of type P) with the builder
 2) save it to a file with save_model
 3) pass the file to netfabb
 4) pass the file to printer's slicer software
 5) print

Useful primitives for printing are at least:
 1) static_instancing
 2) cube/sphere/cone/torus
 3) or_elem