Barry, you do not rotate the solid...you rotate the image mapped to the surface by adjusting its position (U,V,W) on the object you have mapped the matterial to.
To adjust the position of a map on an object or a face
On the dashboard, click Materials Control Panel.
Click and hold the Mapper flyout to display the type of mapping available.
The options on the Mapper flyout are also available as buttons on the Mapper toolbar.
Hover over the mapping you want to use on the object and then release. The following options are available
Planar Mapping
Box Mapping
Spherical Mapping
Cylindrical Mapping
A material mapper grip tool is displayed on the object.
Use the grip tools and the representation of the object to adjust the display of the image on the object or face.
Toolbar: Render
Command entry: MATERIALMAP
After you attach a material with texture, you can adjust the orientation of the texture map on objects or faces.
When materials are mapped, you can adjust the material to fit the shape of the object. Applying the appropriate type of material mapping to an object improves the fit.
Planar mapping. Maps the image onto the object as if you were projecting it from a slide projector onto a 2D surface. The image is not distorted, but the image is scaled to fit the object. This mapping is most commonly used for faces.
Box mapping. Maps an image onto a boxlike solid. The image is repeated on each side of the object.
Spherical mapping. Warps the image both horizontally and vertically. The top edge of the map is compressed to a point at the “north pole” of the sphere, as is the bottom edge at the “south pole.”
Cylindrical mapping. Maps an image onto a cylindrical object; the horizontal edges are wrapped together but not the top and bottom edges. The height of the image is scaled along the cylinder’s axis.
Mapping Gizmo
If you need to make further adjustments, you can use the mapping gizmo that is displayed on the object to move or rotate the map on the object.