Use this procedure to trim hatches, lines, polylines, arcs, circles, AEC polygons, mass element extrusions, spaces, or any block-based content (including detail components) made up of these types of linework or objects.
The trim line changes color once the second point is selected, as does all linework (except hatches) on the side of the trim line where the cursor is positioned.
All linework on the selected side of the trim line is removed, and boundaries for any closed polylines on the other side are redrawn along the trim line.
Trimming a block