A cutting plane represents an imaginary plane or section where an object is cut to reveal its internal details. It acts as a visual indicator, helping viewers understand the hidden features within a solid object or component. The cutting plane line is typically drawn as a thick line with evenly spaced dashes, which distinguish it from other lines in the drawing. Cutting plane lines may also be represented with a heavy phantom line, or as corner indicators.
The ends of cutting plane lines are terminated at the ends with short lines at 90° which are terminated with arrowheads.
To further enhance the clarity and comprehensibility of the drawing, cutting plane lines are accompanied by section symbols. These symbols are placed at the ends of the cutting plane line, indicating the direction and extent of the cut or section being represented. These symbols commonly include letters, such as “A-A” or “B-B,” along with arrows to show the direction of the viewer’s perspective.
Cutting plane lines may be used to indicate viewing planes that are not section views.
See also: Section Lining