1.3Modification tools: move, copy, rotate, scale, mirror, offset
You spend more time modifying a drawing than creating it. AutoCAD offers a palette of fundamental editing commands: Move (MOVE/M), Copy (COPY/CO), Rotate (ROTATE/RO), Scale (SCALE/SC), Mirror (MIRROR/MI), Offset (OFFSET/O). They combine with snaps to edit quickly and exactly.
The principle is always the same: start the command, select the objects, then answer the prompts (base point, distance, angle…). Two star commands deserve special attention: Offset (create parallels at a given distance — ideal for walls, outlines) and Mirror (symmetries). Mastering these tools means editing a drawing in seconds rather than redrawing everything.
Section vocabulary
- Move / Copy
- MOVE (M): move objects. COPY (CO): duplicate them. Base point + destination.
- Rotate / Scale
- ROTATE (RO): pivot around a point. SCALE (SC): enlarge/reduce by a factor.
- Offset (OFFSET / O)
- Create a parallel copy at a given distance: widely used for walls, outlines, curves.
- Mirror (MIRROR / MI)
- Create a symmetrical image of objects about an axis.
- Base point
- Reference point from which the move, copy or rotation is performed.
To create a parallel wall at an exact distance, which command?
In practice — Editing a drawing efficiently
- Move (M) an object by choosing a precise base point (snap) and a destination.
- Copy (CO) an object several times, then apply a Rotate (RO) and a Scale (SC) with a factor.
- Create parallels with Offset (O): enter a distance, click the object, then the side — perfect for walls.
- Use Mirror (MI) to symmetrically duplicate part of the drawing about an axis.
Key points to remember
- You modify more than you create: editing commands are essential.
- Fundamentals: Move, Copy, Rotate, Scale, Mirror, Offset.
- Principle: command → selection → prompts (base point, distance, angle).
- Offset (parallels) and Mirror (symmetries) are everyday stars.
Frequently asked questions
Should you start the command before or after selecting objects?
Both work. You can select first then start the command (via grips), or start the command then select (classic method, the "Select objects" prompt). Many professionals start the command first, because AutoCAD then guides them step by step through its prompts. The key is to follow the command line, which always tells you the expected step.
Offset or Copy to create a parallel wall?
Offset (O), without hesitation: it creates a parallel copy at an exact distance you enter, which is precisely what you need for a wall duplicate, an interior outline, a parallel curve. Copy duplicates to a free location but does not guarantee parallelism or distance. Offset is the dedicated tool for precise parallels.