How to Add Tolerances in SolidWorks?
What are Tolerances?
Tolerances are an essential aspect of engineering design, as they define the acceptable variation in the size, shape, and position of a manufactured part or assembly. In SolidWorks, tolerances are used to specify the limits of variation in a design, ensuring that the manufactured product meets the required specifications.
How to Add Tolerances in SolidWorks?
Adding tolerances in SolidWorks is a straightforward process that can be accomplished in a few steps:
Step 1: Create a New Sketch
To add tolerances in SolidWorks, you need to create a new sketch using the Sketch tool. This will be the foundation of your 3D model, where you can define the tolerances for the geometry of your part or assembly.
Step 2: Define the Geometric Tolerance
There are two types of geometric tolerances: Bilateral and Unilateral. Bilateral tolerance allows for a specific amount of variation on both sides of the nominal size, while unilateral tolerance allows for variation only on one side.
- Bilateral Tolerance: This type of tolerance is used when the design requires equal amounts of variation on both sides of the nominal size.
- Unilateral Tolerance: This type of tolerance is used when the design requires a specific amount of variation only on one side of the nominal size.
Step 3: Define the Position Tolerance
Position tolerance defines the acceptable variation in the position of a part or assembly within a reference position. This tolerance is usually specified as a distance or angle from the nominal position.
- Position Tolerance Type: There are two types of position tolerance: Total Runout Tolerance and Pattern Tolerance. Total runout tolerance accounts for variations in both the position and orientation of the part, while pattern tolerance accounts for variations only in position.
- Position Tolerance Value: The value of the position tolerance is specified in the units of measurement, such as inches, millimeters, or degrees.
Step 4: Define the Size Tolerance
Size tolerance defines the acceptable variation in the size of a part or feature. There are two types of size tolerance: linear size tolerance and angular size tolerance.
- Linear Size Tolerance: This type of tolerance is used for 2D and 3D features, such as holes, slots, and corners.
- Angular Size Tolerance: This type of tolerance is used for angular features, such as angles and curves.
Step 5: Add Tolerances to a Part or Assembly
Once you have defined the tolerances, you can add them to a part or assembly in SolidWorks using the Tolerance tool. This tool allows you to associate the tolerances with specific features or entities in your design.
- Tolerances on Sketch Entities: You can add tolerances to individual sketch entities, such as lines, arcs, and circles.
- Tolerances on 3D Features: You can also add tolerances to 3D features, such as surfaces, edges, and vertices.
Best Practices for Adding Tolerances in SolidWorks
- Use specific tolerance values: Use specific values for your tolerances, rather than general terms like "inch" or "millimeter".
- Use consistent units: Use consistent units throughout your design, such as inches or millimeters.
- Use reference planes: Use reference planes to help define the position and orientation of your tolerances.
Troubleshooting Tolerances in SolidWorks
- Invalid Tolerance: If your tolerance is invalid, SolidWorks will display an error message indicating why the tolerance is invalid.
- Tolerance Interference: If two or more tolerances interfere with each other, SolidWorks will display a warning message indicating the problem.
Conclusion
Adding tolerances in SolidWorks is a crucial step in ensuring that your design meets the required specifications. By following the steps outlined in this article, you can add tolerances to your part or assembly, and ensure that your design is manufacturable and meets the required quality standards.
Table: SolidWorks Tolerance Types
| Tolerance Type | Description | Example |
|---|---|---|
| Bilateral | Equal variation on both sides of the nominal size | +/- 0.005 inch |
| Unilateral | Variation only on one side of the nominal size | +0.005 inch |
| Total Runout | Variation in position and orientation | 0.010 inch |
| Pattern | Variation in position only | 0.015 degree |
| Linear Size | Variation in linear features | 0.005 inch |
| Angular Size | Variation in angular features | 0.01 degree |