To Fillet a Corner (AutoCAD Mechanical Toolset)

You can use the AMFILLET2D command to fillet a corner formed by two line segments, two arc segments, or an arc and a line.

1. Click Home tabModify panelFillet. Find
2. 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.
3. Click an empty space in the drawing area.
4. Select the first line or arc that forms the corner.
5. Select the second line or arc that forms the corner.