1. It’s a
Fine Line !

3. Visible Object Lines
Visible Object Lines
Visible Object Lines are drawn to represent the edges of an object.

4. Hidden Lines
Hidden Lines
Hidden Lines are drawn to represent edges that are inside or hidden from view.

5. Center Lines
Center
Lines
Center Lines are drawn to show the center of holes and the center of symmetrical objects.

6. Dimension Text
Dimension Line
Extension Line
Dimension Text illustrates the actual size of an object.
Dimension Line with arrow heads are drawn the length of the dimension.
Extension Lines are drawn from the edges of the object that represent the dimension.

7. Leader Text
Diameter Symbol
Leader Line
Leader Line drawn with arrowhead pointing to the center of the circle.
Leader Symbol for diameter (O with a slash through the center).
Leader Text completes the dimension for the diameter of the cylinder.

8. Cutting Plane Line
Section Lines
Cutting Plane Line is drawn to represent an imaginary cut into an objects surface.
Section Lines are drawn to represent the inside surface of the imaginary cut into the object.

9. Short Break Line
Short Break Lines are drawn with freehand or irregular lines to represent breaks for detailing surfaces.

10. Long Break Line
Long Break Lines are used when it is best to shorten the long view of an object.

11. Phantom Line
Phantom Lines are drawn to represent alternate positions of a moving part.