To Fillet an Entire Polyline (AutoCAD Mechanical Toolset)

You can fillet all vertexes of a polyline at the same time.

Note: Only the segments long enough to accommodate the fillet is filleted.

Click Home tabModify panelFillet. Find
Enter P for polyline.
On the ribbon, in the Fillet Options panel, check the fillet size. To change the fillet radius:
1. Click <Current tab>Fillet Options panelFillet Size drop-down. Find
2. Select the desired fillet size from the drop-down.
Click an empty space in the drawing area.
Select the polyline.