MIRROR command in AutoCAD - Step-by-Step Guide

Introduction

The MIRROR command in AutoCAD helps you create a flipped copy of selected objects. It is useful when you want to duplicate shapes or designs symmetrically without redrawing them.

When you need to create a symmetrical part of a design, like the left side of a building mirrored to the right side.

When you want to quickly duplicate a logo or symbol flipped horizontally or vertically.

When you have a complex shape and want to create its mirror image to save drawing time.

When designing mechanical parts that require exact mirrored halves.

When you want to check how a design looks flipped before finalizing it.

Steps

Step 1: Type MIRROR and press Enter

- Command line

AutoCAD prompts you to select objects to mirror

💡 You can also find the Mirror tool in the Modify panel on the Home tab

Step 2: Select the objects you want to mirror and press Enter

- Drawing area

AutoCAD prompts you to specify the first point of the mirror line

💡 Use object snaps to pick precise points

Step 3: Click to specify the first point of the mirror line

- Drawing area

AutoCAD prompts you to specify the second point of the mirror line

Step 4: Click to specify the second point of the mirror line

- Drawing area

AutoCAD asks if you want to delete the original objects (Yes/No)

Step 5: Type N and press Enter to keep the original objects

- Command line

A mirrored copy of the selected objects appears on the opposite side of the mirror line

Before vs After

Before

A single rectangle shape on the left side of the drawing area

After

The original rectangle remains, and a flipped copy appears symmetrically on the right side

Settings Reference

Delete Original

📍 Command line prompt during MIRROR command

Decides whether to keep or remove the original objects after mirroring

Default: No

Mirror Line Points

📍 Drawing area during MIRROR command

Defines the axis along which the objects are mirrored

Default: User defined

Common Mistakes

Deleting original objects unintentionally

Choosing Yes at the delete original prompt removes the original shape, which may not be desired

Type N to keep the original objects unless you want to replace them

Picking incorrect mirror line points

The mirror line defines how the object flips; wrong points cause unexpected results

Use object snaps and carefully select the mirror line points to get the desired flip

Summary

The MIRROR command creates a flipped copy of selected objects along a user-defined axis.

You can choose to keep or delete the original objects after mirroring.

Careful selection of the mirror line points ensures the mirrored object appears as intended.

Practice

1. What does the MIRROR command do in AutoCAD?

easy

A. Creates a flipped copy of selected objects

B. Deletes selected objects permanently

C. Rotates objects around a point

D. Scales objects to a new size

Solution

1. Step 1: Understand the MIRROR command purpose

   The MIRROR command is used to create a flipped copy of selected objects across a mirror line.

2. Step 2: Compare options with command function

   Only Creates a flipped copy of selected objects describes creating a flipped copy, which matches the MIRROR command's function.

3. Final Answer:

   Creates a flipped copy of selected objects -> Option A

4. Quick Check:

   MIRROR = flipped copy [OK]

Hint: MIRROR flips objects like a reflection [OK]

Common Mistakes:

• Confusing MIRROR with DELETE command
• Thinking MIRROR rotates objects
• Assuming MIRROR scales objects

2. Which of the following is the correct syntax to start the MIRROR command in AutoCAD?

easy

A. MIRR

B. MIRROR

C. MIRRORR

D. MIR

Solution

1. Step 1: Recall the exact command name

   The correct command to start mirroring is MIRROR.

2. Step 2: Check each option for correctness

   Only MIRROR matches the full and correct command name; others are incorrect or invalid.

3. Final Answer:

   MIRROR -> Option B

4. Quick Check:

   Command syntax = MIRROR [OK]

Hint: Type full command MIRROR to avoid errors [OK]

Common Mistakes:

• Using incomplete command like MIR or MIRR
• Adding extra letters like MIRRORR
• Assuming abbreviations always work

3. You select a rectangle and use the MIRROR command with mirror line points at (0,0) and (0,5). You choose to keep the original objects. What will be the result?

medium

A. The rectangle is deleted and replaced by a flipped copy

B. Only the original rectangle remains, no copy created

C. A flipped copy of the rectangle across the vertical line x=0, plus the original rectangle

D. A rotated copy of the rectangle around point (0,0)

Solution

1. Step 1: Identify mirror line and effect

   The mirror line is vertical at x=0, so the rectangle will be flipped horizontally across this line.

2. Step 2: Consider the option to keep original objects

   Choosing to keep originals means both the original and flipped copy will appear.

3. Final Answer:

   A flipped copy of the rectangle across the vertical line x=0, plus the original rectangle -> Option C

4. Quick Check:

   Mirror line vertical + keep original = flipped copy + original [OK]

Hint: Mirror line flips; keep original means both appear [OK]

Common Mistakes:

• Thinking original is deleted when 'keep' is chosen
• Confusing mirror with rotation
• Ignoring mirror line orientation

4. You tried to mirror a circle but after entering the two mirror points, AutoCAD gave an error and did not create the mirrored object. What is the most likely cause?

medium

A. The two mirror points are the same point

B. The circle is locked and cannot be mirrored

C. You forgot to select the circle before starting MIRROR

D. The MIRROR command does not work on circles

Solution

1. Step 1: Analyze mirror line points

   If the two mirror points are the same, the mirror line is invalid (zero length), causing an error.

2. Step 2: Check other options

   Circles can be mirrored, and selection is required before command, but error after points means mirror line issue.

3. Final Answer:

   The two mirror points are the same point -> Option A

4. Quick Check:

   Mirror line must have two distinct points [OK]

Hint: Mirror line needs two different points [OK]

Common Mistakes:

• Assuming MIRROR can't work on circles
• Forgetting to select objects before MIRROR
• Ignoring mirror line validity

5. You want to create a symmetrical floor plan by mirroring half of the design along a horizontal axis at y=10, keeping both the original and mirrored halves. Which steps should you follow?

hard

A. Select half design -> ROTATE command -> pick center (0,10) -> rotate 180 degrees

B. Select half design -> MIRROR command -> pick mirror line points (0,10) and (5,10) -> choose 'No' to keep original

C. Select full design -> MIRROR command -> pick mirror line points (0,0) and (10,0) -> choose 'No' to keep original

D. Select half design -> MIRROR command -> pick mirror line points (0,10) and (5,10) -> choose 'Yes' to keep original

Solution

1. Step 1: Select the correct half and mirror line

   Select the half design to mirror and use a horizontal mirror line at y=10 by picking points (0,10) and (5,10).

2. Step 2: Choose to keep original after mirroring

   Choosing 'Yes' to "Erase source objects?" means the original objects are kept, so both the original and mirrored halves appear to form the symmetrical floor plan.

3. Final Answer:

   Select half design -> MIRROR command -> pick mirror line points (0,10) and (5,10) -> choose 'Yes' to keep original -> Option D

4. Quick Check:

   Mirror half + horizontal line + keep original = symmetrical plan [OK]

Hint: Pick mirror line, choose 'Yes' to keep original [OK]

Common Mistakes:

• Choosing 'No' deletes original, leaving only mirrored side
• Using ROTATE instead of MIRROR
• Selecting full design instead of half