How to Check Undercut in SolidWorks: Step-by-Step Guide
In SolidWorks, you can check for undercuts by using the
Draft Analysis tool found under the Evaluate tab. This tool highlights areas where the draft angle is insufficient, indicating potential undercuts that may cause issues in molding or manufacturing.Syntax
The Draft Analysis tool in SolidWorks is accessed via the Evaluate tab. You select the faces to analyze, set the draft angle, and choose the direction of pull. The tool then visually highlights areas that do not meet the draft criteria, indicating undercuts.
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1. Open your part in SolidWorks. 2. Go to the Evaluate tab. 3. Click on Draft Analysis. 4. Select the faces to analyze. 5. Set the draft angle (e.g., 1° or 2°). 6. Define the pull direction (usually the mold opening direction). 7. Click OK to see the undercut areas highlighted.
Example
This example demonstrates how to use Draft Analysis to find undercuts on a simple molded part.
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1. Open a part with angled faces in SolidWorks. 2. Navigate to the Evaluate tab and select Draft Analysis. 3. Select all faces of the part. 4. Enter a draft angle of 2 degrees. 5. Set the pull direction along the main axis of the part. 6. Click OK. The software will color-code faces: green for acceptable draft, red for undercut areas.
Output
Faces with insufficient draft angle are highlighted in red, showing undercut zones that may cause molding issues.
Common Pitfalls
- Not setting the correct pull direction can give false undercut results.
- Choosing an inappropriate draft angle may miss subtle undercuts or flag acceptable areas.
- For complex parts, selecting all relevant faces is crucial; missing faces can hide undercuts.
- Ignoring the draft analysis results can lead to manufacturing defects.
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Wrong way: - Using default pull direction without verifying mold opening. - Setting draft angle too low (e.g., 0°) which flags all faces as undercut. Right way: - Confirm mold pull direction before analysis. - Use realistic draft angles based on manufacturing specs (e.g., 1°-3°).
Quick Reference
| Step | Action | Tip |
|---|---|---|
| 1 | Open part in SolidWorks | Ensure part is fully modeled |
| 2 | Go to Evaluate tab | Find Draft Analysis tool |
| 3 | Select faces to analyze | Include all mold-relevant faces |
| 4 | Set draft angle | Use manufacturer recommended angle |
| 5 | Set pull direction | Align with mold opening direction |
| 6 | Run analysis | Review color-coded results for undercuts |
Key Takeaways
Use the Draft Analysis tool under the Evaluate tab to check for undercuts.
Set the correct pull direction to get accurate undercut detection.
Choose an appropriate draft angle based on manufacturing requirements.
Review highlighted areas carefully to avoid molding defects.
Always include all relevant faces in the analysis for complete results.