Always tough googling something when you're looking for the name to google in the first place. I needed the "dihedral angle" of a dodecahedron, meaning the angle between the sides / faces of the body. It's 116.56505°. The cool thing is, with that Angle I can basically nibble away all sides and have the perfect folding angle for this! But for now I just eye-balled it.

// 

difference()
{
    cylinder(3, 35, 33.15, $fn=5);
    union() {
        color("red") cylinder(1, 30 , 30, $fn=5);
        color("red")translate([0,0,1]) cylinder(2, 32 , 31, $fn=5);
    }
}

translate([-31, -25, 6]) rotate([ 0, 116.56505, 0]) cube([5,50,5]);