What is the name of the line drawn on a drawing to define where a cut is made to create a section plane?

• A. Cutting Plane Line
• B. Section View
• C. Detail View
• D. Counter Bore

Answer: (A)

In technical drawings, the line that marks where the object is cut to reveal an interior view is called the cutting plane line. This line defines the exact plane along which material is imagined to be sliced, and is often drawn with a bold or dashed style and arrows at the ends to show the direction of sight for the section. Once this plane is shown, the section view is created to display what the object looks like inside along that plane, helping engineers understand hidden features. The other terms describe different things: a section view is the resulting interior view, a detail view is a magnified portion of the drawing, and a counter bore is a specific hole feature, not the line that defines the cut.