Draft analysis for molding in Solidworks - Real Business Scenario

Scenario Mode

👤 Your Role: You are a product design engineer working with injection molded plastic parts.

📋 Request: Your manager wants you to perform a draft analysis on a new plastic part design to ensure it can be easily removed from the mold without damage.

📊 Data: You have the 3D CAD model of the plastic part in SolidWorks. The model includes all surfaces and features. You will use SolidWorks Draft Analysis tool to check draft angles.

🎯 Deliverable: Produce a report with draft analysis visuals highlighting areas with insufficient draft angles and a summary table of draft angle measurements.

Sample Data

Surface ID	Surface Type	Draft Angle (degrees)
1	Side Face	1.5
2	Side Face	0.5
3	Side Face	2.0
4	Bottom Face	0.0
5	Side Face	1.0
6	Side Face	0.2
7	Top Face	3.0
8	Side Face	0.8

1

Step 1: Open the plastic part model in SolidWorks.

No formula needed.

Expected Result

The 3D model of the plastic part is loaded and visible.

2

Step 2: Activate the Draft Analysis tool from the Evaluate tab.

Click Evaluate > Draft Analysis.

Expected Result

Draft Analysis property manager opens.

3

Step 3: Set the mold pull direction to the main axis of the part.

Select the face or edge that represents the mold pull direction.

Expected Result

Draft analysis aligns with the mold pull direction.

4

Step 4: Set the minimum draft angle to 1 degree to highlight insufficient draft areas.

Enter 1° in the Minimum Draft Angle field.

Expected Result

Surfaces with draft angles less than 1° are highlighted in red.

5

Step 5: Review the color-coded draft analysis on the model to identify problem areas.

No formula needed.

Expected Result

Surfaces with draft angles below 1° are clearly visible in red.

6

Step 6: Generate a summary table listing each surface and its draft angle.

Use the Measure tool or Draft Analysis report feature to record draft angles.

Expected Result

A table showing Surface ID, Surface Type, and Draft Angle is created.

7

Step 7: Export the draft analysis visuals and summary table into a report document.

Use File > Save As or Export options to save images and tables.

Expected Result

A report file with draft analysis images and draft angle table is ready for review.

Final Result

Draft Analysis Report
=====================

Surfaces with draft < 1° are highlighted in RED.

Surface ID | Surface Type | Draft Angle (°)
--------------------------------------------
1          | Side Face   | 1.5
2          | Side Face   | 0.5  <-- Insufficient draft
3          | Side Face   | 2.0
4          | Bottom Face | 0.0  <-- No draft
5          | Side Face   | 1.0
6          | Side Face   | 0.2  <-- Insufficient draft
7          | Top Face    | 3.0
8          | Side Face   | 0.8  <-- Insufficient draft

Color Legend:
- Red: Draft angle < 1° (problem areas)
- Green: Draft angle ≥ 1° (acceptable)

✓Several side faces have draft angles below 1°, which may cause molding issues.

✓The bottom face has zero draft and will likely cause part sticking in the mold.

✓Top face and some side faces have sufficient draft angles for easy mold release.

✓Recommend redesigning surfaces with draft angles below 1° to improve manufacturability.

Bonus Challenge

Create a custom SolidWorks macro that automatically highlights surfaces with draft angles below a user-defined threshold and exports the summary table.

Show Hint

Use SolidWorks API to access draft analysis data and automate color highlighting and report generation.

Practice

1. What is the main purpose of Draft Analysis in SolidWorks molding?

easy

A. To measure the thickness of the part

B. To design the mold cooling channels

C. To calculate the weight of the molded part

D. To check if part surfaces have the correct angles for easy mold release

Solution

1. Step 1: Understand Draft Analysis purpose

   Draft analysis is used to verify if surfaces have the right draft angles to allow easy removal from the mold.

2. Step 2: Compare options with purpose

   Only To check if part surfaces have the correct angles for easy mold release matches this purpose; others relate to different mold design aspects.

3. Final Answer:

   To check if part surfaces have the correct angles for easy mold release -> Option D

4. Quick Check:

   Draft analysis = check draft angles [OK]

Hint: Draft analysis checks angles for mold release [OK]

Common Mistakes:

• Confusing draft analysis with thickness measurement
• Thinking draft analysis calculates weight
• Assuming draft analysis designs cooling

2. Which of the following is the correct step to start a draft analysis in SolidWorks?

easy

A. Open the mold tool and select 'Thickness Check'

B. Select the part, then click on 'Evaluate' tab and choose 'Draft Analysis'

C. Go to 'Insert' menu and select 'Mass Properties'

D. Right-click on the part and select 'Add Material'

Solution

1. Step 1: Identify correct menu path for draft analysis

   Draft analysis is found under the 'Evaluate' tab in SolidWorks.

2. Step 2: Match options with correct path

   Select the part, then click on 'Evaluate' tab and choose 'Draft Analysis' correctly describes selecting the part, then using 'Evaluate' > 'Draft Analysis'. Others are unrelated.

3. Final Answer:

   Select the part, then click on 'Evaluate' tab and choose 'Draft Analysis' -> Option B

4. Quick Check:

   Draft analysis location = Evaluate tab [OK]

Hint: Find draft analysis under Evaluate tab [OK]

Common Mistakes:

• Confusing draft analysis with thickness check
• Looking under Insert menu incorrectly
• Trying to add material instead of analyzing draft

3. Given a part with a pull direction set incorrectly, what will the draft analysis color code likely show?

medium

A. Incorrect color coding, possibly red or no draft shown

B. No color changes, draft analysis will not run

C. Only the edges highlighted in blue

D. All surfaces green indicating good draft

Solution

1. Step 1: Understand pull direction role in draft analysis

   Pull direction defines how the mold opens; incorrect setting causes wrong draft angle evaluation.

2. Step 2: Predict color code effect

   Wrong pull direction leads to incorrect or misleading color coding, often showing red or no draft indication.

3. Final Answer:

   Incorrect color coding, possibly red or no draft shown -> Option A

4. Quick Check:

   Wrong pull direction = wrong color code [OK]

Hint: Wrong pull direction causes wrong draft colors [OK]

Common Mistakes:

• Assuming all green means good draft despite wrong pull
• Thinking edges only get highlighted
• Believing draft analysis won't run at all

4. You ran draft analysis but the colors do not match expected draft angles. What is the most likely error?

medium

A. Draft analysis was run on a 2D sketch

B. The part has no material assigned

C. Pull direction is set incorrectly

D. The computer graphics driver is outdated

Solution

1. Step 1: Identify common causes of wrong draft colors

   Incorrect pull direction is the most common cause for wrong draft color results.

2. Step 2: Evaluate other options

   No material or 2D sketch won't run draft analysis properly, but usually cause errors, not wrong colors. Graphics driver affects display but not analysis logic.

3. Final Answer:

   Pull direction is set incorrectly -> Option C

4. Quick Check:

   Wrong colors = wrong pull direction [OK]

Hint: Check pull direction first if colors seem wrong [OK]

Common Mistakes:

• Ignoring pull direction as cause
• Blaming material assignment
• Thinking 2D sketches can show draft colors

5. You want to ensure a part has a minimum draft angle of 3 degrees for molding. How do you set this in SolidWorks draft analysis?

hard

A. Set the draft angle value to 3 degrees in the draft analysis property manager

B. Change the pull direction to 3 degrees

C. Apply a 3-degree fillet to all edges

D. Increase the part thickness by 3 mm

Solution

1. Step 1: Identify how to specify draft angle in analysis

   In draft analysis, you set the minimum draft angle to check surfaces against that value.

2. Step 2: Evaluate options for setting draft angle

   Set the draft angle value to 3 degrees in the draft analysis property manager correctly describes setting the draft angle in the property manager. Others change geometry or pull direction incorrectly.

3. Final Answer:

   Set the draft angle value to 3 degrees in the draft analysis property manager -> Option A

4. Quick Check:

   Minimum draft angle set in property manager [OK]

Hint: Set draft angle in property manager, not geometry [OK]

Common Mistakes:

• Changing pull direction instead of angle value
• Adding fillets instead of setting draft angle
• Modifying thickness unrelated to draft