While detailing the 2D Fabrication drawings, you may want to display only a part of the entire 2D structural member or group. You can do this by the 2D Cutout tool, as this allows you to place a bounding polygon in a 2D drawing view and will trim all the lines extending out of the bounding polyline shape. This document will assist you on how to use the 2D Cutout tool to clip a part of the 2D drawing in the model and display the same.
1) Place a 2D drawing in the model OR open a DGN file that contains a 2D drawing. 2) Now, open the ‘Named Groups’ dialog box by navigating to Drawing > Home > Groups 3) In the ‘Named Groups’ dialog box, check off all the tick marks in the ‘Selectable’ column. 4) After this, you need to drop the 2D drawing to simple elements like lines, curves, etc. To do this, use the ‘Drop Element’ command under Steel > Drawing Production > Common Tools 5) With the ‘Drop Element’ dialog box opened, select the entire 2D drawing and then right click to Accept your selection set and then this drawing will be converted to lines, curves, etc. 6) Finally, click on the ‘2D Cutout’ tool under Steel > Drawing Production > Detailing 7) With the command open, create a bounding area by setting a closed area of polylines. 8) Once you have completed your area of selection and choose to close the area, all the lines extending past the smartline just drawn are cut off at this line and only the lines contained inside are retained. In this manner, you can choose to display only a section or area of importance (as per your requirement) in the entire 2D fabrication drawing of a part, group or assembly.
how to create automatic 2d cut and show section in drawing block via detail center