Snap-together Icosahedron (d20)

thingiverse

Print 20 of these triangular modules and snap them together to get a nice smooth surface on every side of your d20! Print without a raft or supports, assuming your printer can handle small overhangs. Snapping them together one-by-one would be near impossible, as the final piece doesn't have enough clearance; I recommend constructing two 5-sided pyramids and snapping those on to either side of a ring of 10 (see photos).