REVOLVE command in AutoCAD - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the REVOLVE command do in AutoCAD?

The REVOLVE command creates a 3D solid or surface by rotating a 2D object around an axis.

beginner

Which type of objects can you revolve using the REVOLVE command?

You can revolve 2D objects like lines, arcs, circles, or polylines to create 3D shapes.

beginner

What is the role of the axis in the REVOLVE command?

The axis is the line around which the 2D object rotates to form the 3D shape.

intermediate

How do you specify the angle of revolution in the REVOLVE command?

You enter the angle in degrees to control how far the object revolves around the axis, up to 360° for a full revolution.

intermediate

Can the REVOLVE command create both solids and surfaces?

Yes, depending on the options chosen, REVOLVE can create either 3D solids or 3D surfaces.

What is the first step when using the REVOLVE command?

A Specify the axis of revolution

B Select the 2D object to revolve

C Enter the angle of revolution

D Choose the 3D solid or surface option

You first select the 2D object that you want to revolve.

What does revolving a 2D shape 360 degrees create?

A A 3D solid or surface

B A 2D line

C A flat 2D shape

D A 3D wireframe only

Revolving 360 degrees creates a full 3D solid or surface.

Which of these can NOT be used as an axis for the REVOLVE command?

A A line

B An arc

C A circle

D A point

The axis must be a line or linear object, not a single point.

If you want only half a revolution, what angle do you enter?

A 180 degrees

B 90 degrees

C 270 degrees

D 360 degrees

180 degrees creates a half revolution.

Which option lets you create a surface instead of a solid with REVOLVE?

A Solid option

B Wireframe option

C Surface option

D Mesh option

Choosing the surface option creates a 3D surface instead of a solid.

Explain how the REVOLVE command transforms a 2D shape into a 3D object.

Think about spinning a flat shape around a line to make a 3D form.

Describe the importance of the axis in the REVOLVE command and what happens if you change it.

The axis is like the stick you spin a wheel around.

Practice

1.

What does the REVOLVE command do in AutoCAD?

easy

A. It changes the color of a 2D shape.

B. It copies objects to multiple locations.

C. It creates a 3D object by spinning a 2D shape around an axis.

D. It flattens 3D objects into 2D drawings.

Solution

1. Step 1: Understand the purpose of REVOLVE

   The REVOLVE command spins a 2D shape around an axis to create a 3D object.

2. Step 2: Compare options

   "It creates a 3D object by spinning a 2D shape around an axis." is the only description that matches REVOLVE; others describe unrelated actions.

3. Final Answer:

   It creates a 3D object by spinning a 2D shape around an axis. -> Option C

4. Quick Check:

   REVOLVE = 3D spin [OK]

Hint: REVOLVE spins 2D shapes into 3D objects [OK]

Common Mistakes:

• Confusing REVOLVE with COPY command
• Thinking REVOLVE changes colors
• Assuming REVOLVE flattens objects

2.

Which of the following is the correct basic syntax to start the REVOLVE command in AutoCAD?

easy

A. Type REVOLVE3D and press Enter.

B. Type REVOLVE and press Enter.

C. Type REVOLV and press Enter.

D. Type REV and press Enter.

Solution

1. Step 1: Recall the exact command name

   The correct command to start revolve is REVOLVE.

2. Step 2: Check options for exact match

   Only "Type REVOLVE and press Enter." matches the exact command name; others are incorrect or incomplete.

3. Final Answer:

   Type REVOLVE and press Enter. -> Option B

4. Quick Check:

   Command name = REVOLVE [OK]

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

Common Mistakes:

• Typing incomplete command names
• Adding extra characters to command
• Using abbreviations not recognized

3.

Given a 2D semicircle with radius 5 units, if you use the REVOLVE command to spin it 360 degrees around its straight edge, what 3D shape will you get?

medium

A. A sphere with radius 5 units.

B. A cylinder with height 5 units.

C. A cone with base radius 5 units.

D. A torus (donut shape).

Solution

1. Step 1: Understand the shape and axis

   Revolving a semicircle around its straight edge spins the curve fully, creating a sphere.

2. Step 2: Match shape to options

   A full revolution of a semicircle creates a sphere, not cylinder, cone, or torus.

3. Final Answer:

   A sphere with radius 5 units. -> Option A

4. Quick Check:

   Semicircle revolve 360° = Sphere [OK]

Hint: Revolve semicircle fully = sphere [OK]

Common Mistakes:

• Confusing cylinder with sphere
• Thinking partial revolve creates cone
• Assuming torus needs semicircle

4.

What is wrong with this use of the REVOLVE command?
REVOLVE a 2D line around an axis to create a 3D object.

medium

A. You must specify the angle as 180 degrees or less.

B. The axis must be a circle, not a line.

C. REVOLVE only works on closed 2D shapes.

D. A single line cannot be revolved to create a solid 3D object.

Solution

1. Step 1: Analyze the shape type

   A single 2D line has no area, so revolving it creates only a surface, not a solid.

2. Step 2: Check axis and angle requirements

   The axis can be any line; REVOLVE works on open or closed shapes; angle can be any value.

3. Final Answer:

   A single line cannot be revolved to create a solid 3D object. -> Option D

4. Quick Check:

   Line revolve ≠ solid [OK]

Hint: Revolve needs area, not just a line [OK]

Common Mistakes:

• Thinking axis must be circle
• Believing REVOLVE needs closed shapes only
• Assuming angle limit is 180 degrees

5.

You want to create a vase shape by revolving a 2D profile. The profile is an open curve with a base line and a curved outline. Which steps should you follow to get a smooth 3D vase using the REVOLVE command?

hard

A. Select the open profile, specify the base line as axis, and revolve 360 degrees.

B. Close the profile shape, select it, specify any axis, and revolve 180 degrees.

C. Select only the curved outline, specify the base line as axis, and revolve 90 degrees.

D. Use the base line as axis, revolve 360 degrees, then extrude the shape.

Solution

1. Step 1: Prepare the profile and axis

   Use the open profile including base line; base line is the axis for revolve.

2. Step 2: Apply revolve with full rotation

   Revolve 360 degrees around base line to create smooth vase shape.

3. Final Answer:

   Select the open profile, specify the base line as axis, and revolve 360 degrees. -> Option A

4. Quick Check:

   Open profile + base line axis + 360° revolve = vase [OK]

Hint: Revolve open profile 360° around base line for vase [OK]

Common Mistakes:

• Not using full 360 degrees revolve
• Revolving only curved outline without base line
• Trying to extrude after revolve unnecessarily