Sweet Home 3D Furniture Library 183.4 kB - 58 models
DodecagonShapes.sh3f
It might seem that some shapes are double in the library but take a careful look at the orientation of the dodecagon shape. In most cases there's a version with a point at the top and the similar version has a flat side at the top. This makes it easier to align shapes depending on the needed orientation without having to rotate the shape. Also partial shapes are either sliced through the middle of a flat side or through opposing corner points.
After I created most of these shapes the "Create basic shape" tool was introduced. You might find it easier to use that tool for some of the the basic shapes.