How does profile of a surface differ from true position?

How does profile of a surface differ from true position?

• A. Profile controls size; true position controls orientation
• B. Profile controls the boundary shape of a surface; true position controls a feature’s location relative to datums.
• C. Profile controls datums; true position controls the envelope
• D. Profile controls material condition; true position controls cylindricity

Answer: (B)

Profile of a surface sets the allowable deviation of the surface boundary from its intended contour, effectively controlling the boundary geometry and form of that surface. It defines how the edge or boundary of the surface must look, rather than where a feature sits in the part or how big the feature is overall. True position specifies how far the actual feature is from its exact location relative to datums, usually with a cylindrical or other location-based tolerance zone that constrains the feature’s center or axis. So profile governs the boundary shape of the surface, while true position governs the feature’s location relative to datums. For example, you’d use profile to ensure a curved outer boundary follows the designed contour, and true position to ensure a hole is centered where it should be with respect to datum references.

Profile of a surface sets the allowable deviation of the surface boundary from its intended contour, effectively controlling the boundary geometry and form of that surface. It defines how the edge or boundary of the surface must look, rather than where a feature sits in the part or how big the feature is overall. True position specifies how far the actual feature is from its exact location relative to datums, usually with a cylindrical or other location-based tolerance zone that constrains the feature’s center or axis. So profile governs the boundary shape of the surface, while true position governs the feature’s location relative to datums. For example, you’d use profile to ensure a curved outer boundary follows the designed contour, and true position to ensure a hole is centered where it should be with respect to datum references.