Why Extruded surface in Solidworks? - Purpose & Use Cases

The Big Idea

What if you could create complex 3D shapes in seconds instead of hours?

The Scenario

Imagine trying to create a complex 3D shape by manually drawing each face and connecting edges one by one in a CAD program without using extrusion tools.

The Problem

This manual method is slow, prone to mistakes, and hard to adjust if you need to change the shape later. It's like building a puzzle without a picture to guide you.

The Solution

Using the Extruded surface feature lets you quickly turn a 2D sketch into a 3D surface by pulling it out in one smooth step, saving time and reducing errors.

Before vs After

✗ Before

Draw face by face; connect edges manually

✓ After

Use Extruded Surface to pull 2D sketch into 3D

What It Enables

It enables fast creation and easy modification of complex 3D surfaces from simple sketches.

Real Life Example

Designers can quickly model car body panels by extruding surface sketches, speeding up prototype development.

Key Takeaways

Manual 3D modeling is slow and error-prone.

Extruded surface turns 2D sketches into 3D shapes easily.

This speeds up design and reduces mistakes.

Practice

1. What is the main characteristic of an Extruded Surface in SolidWorks?

easy

A. It creates a thin 3D shape without volume.

B. It creates a solid 3D object with volume.

C. It only creates 2D sketches.

D. It automatically adds thickness to a solid.

Solution

1. Step 1: Understand the definition of extruded surface

   An extruded surface stretches a 2D sketch into a 3D shape but does not create volume.

2. Step 2: Compare with solid extrusion

   Unlike solid extrusion, extruded surfaces are thin and have no volume.

3. Final Answer:

   It creates a thin 3D shape without volume. -> Option A

4. Quick Check:

   Extruded surface = thin 3D shape without volume [OK]

Hint: Remember: surfaces have no volume, solids do [OK]

Common Mistakes:

• Confusing extruded surface with solid extrusion
• Thinking extruded surfaces add thickness automatically
• Assuming extruded surfaces are 2D only

2. Which of the following is the correct syntax to create an extruded surface in SolidWorks using the feature tree?

easy

A. Right-click sketch > Select 'Extruded Surface'

B. Right-click sketch > Select 'Extruded Boss/Base'

C. Right-click sketch > Select 'Revolve Boss/Base'

D. Right-click sketch > Select 'Cut-Extrude'

Solution

1. Step 1: Identify the correct feature for extruded surface

   The feature to create an extruded surface is called 'Extruded Surface' in SolidWorks.

2. Step 2: Eliminate other options

   'Extruded Boss/Base' creates solids, 'Revolve Boss/Base' is for revolved solids, and 'Cut-Extrude' removes material.

3. Final Answer:

   Right-click sketch > Select 'Extruded Surface' -> Option A

4. Quick Check:

   Extruded surface feature = 'Extruded Surface' [OK]

Hint: Look for 'Surface' keyword in feature name [OK]

Common Mistakes:

• Choosing 'Extruded Boss/Base' which creates solids
• Confusing revolve features with extrusion
• Selecting cut features instead of surface creation

3. Given a 2D sketch of a circle with radius 10mm, what will be the result of applying an extruded surface with a depth of 5mm?

medium

A. A solid cylinder with radius 10mm and height 5mm

B. A flat 2D circle with no thickness

C. A thin cylindrical surface with radius 10mm and depth 5mm

D. A hollow sphere with radius 10mm

Solution

1. Step 1: Understand extrusion of a circle sketch as surface

   Extruding a circle sketch as a surface creates a thin cylindrical shell, not a solid.

2. Step 2: Analyze the depth parameter

   The extrusion depth of 5mm defines how far the surface extends in 3D space.

3. Final Answer:

   A thin cylindrical surface with radius 10mm and depth 5mm -> Option C

4. Quick Check:

   Extruded surface of circle = thin cylinder surface [OK]

Hint: Extruded surface keeps shape but no volume [OK]

Common Mistakes:

• Assuming extrusion creates a solid cylinder
• Thinking extrusion does not add depth
• Confusing surface extrusion with 2D sketch

4. You tried to create an extruded surface but the feature failed. Which of these is the most likely cause?

medium

A. The extrusion depth is set to zero.

B. The sketch is fully defined.

C. You selected 'Extruded Boss/Base' instead of 'Extruded Surface'.

D. The sketch is not closed.

Solution

1. Step 1: Check sketch closure

   An extruded surface requires a closed sketch; an open sketch will cause the feature to fail.

2. Step 2: Review other options

   Zero extrusion depth causes no extrusion but usually does not cause feature failure; selecting wrong feature changes output but not failure; fully defined sketch is good practice and does not cause failure.

3. Final Answer:

   The sketch is not closed. -> Option D

4. Quick Check:

   Open sketch = feature failure [OK]

Hint: Ensure sketch is fully closed before extrusion [OK]

Common Mistakes:

• Ignoring open sketch as failure cause
• Confusing zero depth with failure
• Assuming fully defined sketch causes failure

5. You want to create a thin cover part by extruding a rectangular sketch 2mm as a surface, then offset it by 1mm to create thickness. Which sequence of features should you use?

hard

A. Extruded Surface (2mm) -> Thicken (1mm)

B. Extruded Surface (2mm) -> Offset Surface (1mm) -> Thicken

C. Extruded Boss/Base (2mm) -> Shell (1mm)

D. Extruded Surface (2mm) -> Cut-Extrude (1mm)

Solution

1. Step 1: Create the base thin surface

   Use 'Extruded Surface' with 2mm depth to create the initial thin surface.

2. Step 2: Offset the surface to create thickness

   Apply 'Offset Surface' by 1mm to create a parallel surface at the desired thickness.

3. Step 3: Use 'Thicken' to convert surfaces into a solid with thickness

   Thicken the offset surfaces to form a solid cover part.

4. Final Answer:

   Extruded Surface (2mm) -> Offset Surface (1mm) -> Thicken -> Option B

5. Quick Check:

   Surface extrusion + offset + thicken = solid cover [OK]

Hint: Use offset and thicken after surface extrusion for thickness [OK]

Common Mistakes:

• Using solid extrusion instead of surface extrusion first
• Skipping offset surface step
• Using cut-extrude which removes material