Tutorial - How to make dodecahedron pot
That's what I did.
Draw pentagon, where a is a radius of circumscribed circle.
Create auxiliary datum plane passing trough the rib at an angle equal to the parameter phi.
Draw second pentagon.
Make surfaces of them.
Do copy five surfaces with translation by the amount equal to parameter (2*rad) along Y-axis. The axis Y - perpendicular to the plane of the first pentagon. And rotation axis Z and X on180° and 36°, respectively.
Combine surfaces and do displacement inside.
Closing volume with surfaces. Make solid detail.
Round, round and round.