Here is a free course how to use EXTEND command in AutoCAD
- first you select 2D boundary objects (e.g. LINEs, ARCs, CIRCLEs, ELLIPSEs, POLYLINEs. TEXT & 2D SPLINEs).
- then select 2D objects to extend to the specified boundary.
Current settings: Projection=UCS Edge=None Select boundary edges …
Select objects: (pick LINE)
Select objects: ↵
Select object to extend or [Project/Edge/Undo]: (pick ARC)
Select object to extend or [Project/Edge/Undo]: ↵
- There are other similarities between Trim & Extend
- if you press <enter> instead of selecting boundary objects AutoCAD uses all objects (without highlighting them).
- you can select any number of boundary objects and you select objects to extend one-at-a-time (unless you use a Fence).
- where you select objects to extend is important (select object nearest the end that you want to extend).
- the Edge setting is controlled by (the same) EDGEMODE system variable so boundary objects can imply extended boundaries.
- The Lengthen command also lets you make objects longer (or shorter) without having to use boundary objects.
Practice : HOW TO USER EXTEND COMMAND TUTORIAL IN AUTOCAD
- Close the drawing from the previous exercise if it is open.
- Open the T108_3.dwg drawing file in your personal folder.
- Pick Modify + Extend. Select the horizontal LINE near P1 when prompted for boundary objects and press <enter> to signal AutoCAD that you have selected all boundary objects. Then pick the end of the ARC near P2 when prompted for objects to extend (do not exit this command yet).
- Right-click in the drawing area to invoke a shortcut and select Undo. (Remain in the same Extend command.)
- Pick the two ARCs near P1 & P2 to extend these ends of the ARCs to the boundary object and press <enter> to signal AutoCAD that you have selected all objects to extend.
- Trim the LINE used as the boundary in the last Extend command so your drawing looks like the illustration below.
- Save your changes to this drawing and Close the file.