Last century, Strata Studio Pro used to have a dodecahedron among its primitives, and it is not present any longer. It is not something that sees everyday use, but in case you need one, here’s how to make it.
First, we draw a pentagon centered in the origin of the grids. To create a pentagon, double-click on the 2D Polygon tool and type 5 as the number of sides.
Pentagon centered on the grid origin
Move the centerpoint (Cmd/Ctrl+drag) to the midpoint of a side.
Replicate one copy, with a 116.56º rotation angle on the z-axis.
Move the centerpoint of the new side back to the origin of the grids and replicate again, with the settings below.
This will create 4 more sides.
We now have half a dodecahedron. Looks good but there are gaps to fill. We will use the Snap tool to align everything precisely.
When all is precisely aligned, group
Alt-rotate the group to create a new half-dodecahedron rotated 180º on the z-axis relative to the original one.
Snap the two objects together, group them, and convert into a polygon mesh.
The dodecahedron is ready. You can modify it further in the polygon modeller if you wish.
This is the shape file for the dodecahedron: Dodecahedron.ssh, in case it is of use.
