Giant Pyramid (RD version)

thingiverse

I made this version out of rhombic dodecahedra if you think the sphere version is not challenging enough. There are nine pieces and one solution for the tetrahedron of size 5, using rhombic dodecahedra with a diameter of 2 cm. A great starting challenge is to connect the four L4 pieces to form a truncated tetrahedron of size 4 (see the second photo). An intermediate challenge is to build a pyramid only three layers high, missing one piece (see the third photo). This version is more confusing than the sphere version. Two of the pieces are chiral - J4 and P4. Even C4 and N4 can be different if you flip them over. You'll need four copies of L4, plus one each of I3, C4, J4, N4, and P4 to complete it. L4 and I3 can be printed in one piece, while the remaining pieces are printed in halves (top and bottom). The base plate is optional, but no supports are needed for the pieces or the base plate. Each half-piece contains holes for alignment. After cleaning out any debris from the holes (if necessary), take a scrap piece of 1.75 mm filament and insert it into a hole, cutting it off so about 4 mm sticks out. After each hole has a piece of filament, fit the other half in place. If the fit looks good, remove it and glue the halves together. Be extremely careful when working with N4 as it's possible to glue it together incorrectly.