Purpose of Sectioning

Sectioning is used to show the inside parts of an object where hidden lines would be confusing

Cutting Plane Line

Is the line that shows where the object is cut open.

The arrows indicate the direction of sight.


Full Section

Where the cutting plane line passes completely through the object.

Offset Section

Same as the Full Section, except the cutting plane is offset to pass through several inside parts of the object.

Note: You do not show the line of the offset.

Half Section

Where the cutting plane passes part way through an object.

This is useful for showing both the interior and exterior of an object in one view.

Broken Out Section

Where only a partial section of a view is needed.

Note: The line drawn is a freehand line.

Revolved Section

The shape of the cross section of a bar, arm, spoke, or other object may be shown with a revolved section (as if a thin slice is taken out and turned sideways.)

Removed Sections

Similar to the revolved section but the sections are placed off the object with a centerline designating where the section comes from.

Also the Sections may be off to one side and a letter designation given to identify the location the section came from.

Symbols for Section Lines