This is a triple block soil press, to make starting seedlings cheaper and easier. At full size, the press will create cubes of approximately 45mm. Be sure to print with a high percentage of infil for strength, especially in the shaft of each press (thus the reason for separate files to print.) After printing, use epoxy or silicone to fasten each press into the cross bar. You may also want to attach a small bead or button to the bottom center of each press, to create a nest for the seeds.
To use: After placing the large block on a tray, fill with lightly moistened seedling mix, then press the triple-press into the holes firmly. Begin lifting block away from soil while still pressing down.