To Join Overlapping Entities to Form a Single Element (AutoCAD Mechanical Toolset)
When overlapping entities join to form a single element, the “overlapped” line draws only once during plotting, preventing the plotter pen from tearing the paper.
Click Home tabModify panelJoin. Find
Press Enter.
Select the first object you want to join.
Select the second object.
Note: This procedure cannot be used to join polylines. Also, the selected entities must:
Overlap each other.
Be on the same layer (color, lineweight, linetype).