Interpreting Working Plan and Sketches

This line is used to initially lay out a drawing.

• visible/object

• construction

• center

• hidden

These lines are thick and dark solid (unbroken) lines that are used on drawings to indicate the edges and details of an object.

• visible/object

• construction

• center

• hidden

These lines are medium dashed lines used to indicate a surface, edge, or contour of an object that cannot be seen, or is hidden from view.

• visible/object

• construction

• center

• hidden

These lines are thin lines made up of alternating long and short dashes. They are used to indicate the center of circles and of symmetrical features.

• visible/object

• construction

• center

• hidden

These are thin "cross hatching" lines used in sectional views to symbolize different parts of an object or different materials from which an object is manufactured.

• dimension and leader

• section

• cutting plane or viewing plane

• extension lines

Generally end with arrowheads and are accompanied by a number indicating a size or location dimensions.

• dimension and leader

• section

• cutting plane or viewing plane

• extension

This aid dimension lines by extending the surface of the object so it can be dimensioned.

• dimension and leader

• section

• cutting plane or viewing plane

• extension

These are very thick lines that indicate where an imaginary cutting plane passes through an object, for viewing or sectioning purpose.

• dimension and leader

• section

• cutting plane or viewing plane

• extension

These are thick wavy freehand lines

• section

• phantom

• short break

• long break

These are thin straight zigzags.

• section

• phantom

• short break

• long break