To Customize the Fillet Size List (AutoCAD Mechanical Toolset)
You can predefine chamfer lengths and make them available in drop-down lists in the Chamfer dialog box and the Chamfer Options Ribbon Contextual Panel.
To create a custom list of fillet radii for the Fillet Radius dialog box:
Click Configure (The last item in the drop-down list). The Fillet List Configuration dialog box displays.
To add a new fillet size:
Click Add.
Enter the new fillet size.
Move the new fillet size to the appropriate position by clicking the Move Up and Move Down buttons.
To remove a length from the list:
Click the value to remove.
Click Delete.
To change a fillet size:
Click the value to edit
Click Edit.
Enter the new value
Move the edited value to the appropriate position by clicking the Move Up and Move Down buttons.
Click OK.
Press ESC to exit the command.
Note: The program saves this setting as a registry entry; it does not save it with the drawing. This setting applies across all drawings you open, but will not port with the drawing to other computers.