About Shape Surface Sets
A shape surface set collects the surfaces of the shapes derived from a seed surface. When you select a seed surface a default primary shape is automatically selected. Secondary shapes identified by the system are also included by default in the shape surface set. Remember the following about automatically selected surface sets.
• You do not have to accept the default primary shape, you can select a different shape.
• You can choose to exclude a secondary shape.
• Shape surface sets regenerate when the model is modified.
Surfaces shared by shapes included in a surface set and shapes not included in the surface set are called “bleeding surfaces”. These surfaces are always included in the shape surface set.
You can use shape surface sets to quickly select the surfaces of bosses and ribs. Select the top surface or a side surface as the seed surface.
Primary Shapes
Each tool specifies the eligible primary shapes. The default primary shape is selected in the following order according to preset rules.
1. Chamfer—Selected as the default primary shape when a chamfer can be derived from the seed surface. If a chamfer or a round can be derived from the same seed surface, the chamfer is selected as the default primary shape. A chamfer adds or removes material.
2. Round—Selected as the default primary shape when a round can be derived from the seed surface and a chamfer cannot be derived. A round adds or removes material.
3. Boss—Selected as the default primary shape when the seed surface has only convex edges. A boss adds material.
4. Cut—Selected as the default primary shape when the seed surface has only concave edges. A cut removes volume or material from the model.
5. Size—The smaller shape, when more than one shape can be derived from the seed surface.
6. Shape—A boss, when more than one type of shape is possible.
Secondary Shapes
The following shape types are included as secondary shapes:
• Chamfers that are the same as the primary chamfer and are connected via transitions. The transitions are also included in the surface set.
• Rounds having the same radius and connected via transitions. The transitions are also included in the surface set.
• Bosses smaller than the primary boss shape, and attached to the primary shape directly or via other secondary shapes.
• Cuts smaller than the primary cut shape, and attached to the primary shape directly or via other secondary shapes.
• Through–holes that intersect with at least one surface of the primary shape.