To Modify a Symbol in the Library (AutoCAD Mechanical Toolset)

1. In the drawing area, double-click a symbol of the type of symbol library you want to edit. For example, to modify a symbol in the welding symbol library, double-click a welding symbol.
2. Click Add.
   Note: Step 2 is performed to use the symbol as a temporary symbol library item. You delete it in step 10.
3. Enter TEMP as the name of the symbol.
4. In the library, click the edge symbol to edit.
5. From the drop-down menu on the right, select Load. The selected configuration replaces the information in the dialog box.
6. Modify the symbol as required.
7. From the drop-down menu on the right, select Update. The symbol library is updated with the information in the dialog box.
8. In the library click TEMP.
9. From the drop-down menu on the right, select Load. The selected configuration replaces the information in the dialog box.
10. From the drop-down menu on the right, select Delete. The temporary symbol is deleted.
11. Click OK.