Which line is a heavy solid line used to depict the outline of an object?

Which line is a heavy solid line used to depict the outline of an object?

• A. Construction Line
• B. Hidden Line
• C. Center Line
• D. Object Line

Answer: (D)

In technical drawings, the visible outer boundary of the part is shown with a heavy solid line. This is called the object line, and its darkness and thickness make the outline stand out clearly as the part’s actual edge. Other line types serve different purposes: construction lines are light guidelines used during drafting; hidden lines (dashed) represent edges not visible from the viewing angle; center lines (long and short dashes) indicate axes or symmetry. Because the goal is to convey the true, visible outline of the object, the heavy solid line is the one used for that purpose.

In technical drawings, the visible outer boundary of the part is shown with a heavy solid line. This is called the object line, and its darkness and thickness make the outline stand out clearly as the part’s actual edge. Other line types serve different purposes: construction lines are light guidelines used during drafting; hidden lines (dashed) represent edges not visible from the viewing angle; center lines (long and short dashes) indicate axes or symmetry. Because the goal is to convey the true, visible outline of the object, the heavy solid line is the one used for that purpose.