Next you must get your mind out of the grade line because when we profile in Part Builder, we are creating a closed 2-dimensional shape around the outside of a feature which can be projected away from a plane to a certain distance and/or to a certain shape for the purpose of creating a 3-dimensional figure. Think of the profile of your face defining the 2-dimensional shape of your head; if we extrude away from this profile and transition to your ear we've created half the shape of your head. Sculpting, parametric style.

In an effort to break this information down into palatable chunks, some of these posts will be presented in two parts i.e. A and B parts. Part A will contain definitions and Part B will contain workflow. Here are your definitions for Profiles. We will talk about how these items are used in Part B.

Work Planes: Use work planes to model critical areas of your structure. Any area where a change in geometry occurs should have a work plane assigned to it. For example, a manhole with a conical riser could have a work plane at the top of the frame, one at the intersection of the frame and riser, and one that occurs where the riser meets the barrel of the structure.

Geometry: Within work planes, you would add geometry. Any type of geometry you would draw with an endpoint i.e. a line or arc will come in with its endpoints constrained to points. Think of this as a type of marriage between the points themselves and these endpoints. Geometry used to model parts must be of type AECCU_COL_GEOMETRY which simply means it must be drawn using the tools from the Add Geometry menu. If geometry from one work plane must be used in another work plane, there are commands that will reference that geometry.

Constraints: To set up physical relationships between geometry, constraints are applied. Constraints are used to maintain perpendicular, parallel, concentric, tangent relationships between geometry. Equal dimensional and symmetrical relationships can be set up as well. Coincident constraints ensure that points and endpoints of geometry stay with each other. Normal constraints are applied when the tangent of a curve must remain perpendicular to another curve or line. Midpoint constraints locate the midpoint between two entities. We will talk about applying constraints in Part Builder III. But is important that you understand them as you are creating your profile.

Profiles: When modeling in work planes, geometry is used to create closed areas called profiles. These profiles are then projected away from the work plan for the purpose of creating a 3-dimensional portion of the structure. We create custom profiles by selecting the individual geometry that forms these shapes. However, there are three "quicky" profile tools which define geometry, constraints, and the profile at the same time: circular, rectangular, and oval.

Stay tuned for Part Builder II-B.

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