How do you offset a 3D sketch in Solidworks?

To offset a 3D sketch in SolidWorks, you utilize the Offset Entities tool, following the standard procedure for offsetting entities within any open sketch environment.

Understanding Offset Entities in 3D Sketches

Offsetting sketch entities allows you to create parallel curves from existing sketch geometry, model edges, or model faces at a specified distance. While the process is the same as in 2D sketches, applying it in a 3D sketch lets you offset lines, arcs, or spline curves defined in 3D space or project and offset edges/faces from your existing 3D model directly into your 3D sketch.

The reference provided outlines the core steps:

To create a sketch offset: In an open sketch, select one or more sketch entities, a model face, or a model edge. (Sketch toolbar) or Tools Sketch Tools Offset Entities. Set the properties in the Offset Entities PropertyManager.

This process is exactly how you achieve an offset in a 3D sketch environment within SolidWorks.

Steps to Offset Entities in a 3D Sketch

Here is a breakdown of the process based on the standard SolidWorks workflow, applicable directly to an active 3D sketch:

1. Open or Activate the 3D Sketch: Ensure you are in an active 3D sketch environment.
2. Select Entities:
   • Select the existing sketch entities (lines, arcs, splines, etc.) within your 3D sketch that you wish to offset.
   • Alternatively, you can select model edges or model faces from your 3D part geometry. SolidWorks will project these edges/faces onto a temporary sketch plane to create the offset geometry.
3. Access Offset Entities Tool:
   • Go to the Sketch toolbar and click Offset Entities.
   • Or, navigate through the menu: Tools > Sketch Tools > Offset Entities.
4. Configure Properties: The Offset Entities PropertyManager will appear. This is where you define the offset parameters:
   • Offset Distance: Specify the desired distance for the offset.
   • Select Chain: Often enabled by default, this attempts to select connected entities automatically.
   • Add Dimensions: Creates a dimension for the offset distance, allowing easy modification later.
   • Reverse: Changes the direction of the offset (inward or outward relative to the original geometry or projected edge/face).
   • Bi-directional: Creates an offset in both directions from the original geometry.
   • Cap Ends: Allows you to close the ends of the offset geometry with lines or arcs if the original selection was open.
5. Preview and Apply: SolidWorks provides a preview of the offset geometry based on your settings. Review the preview and click the green checkmark (✓) in the PropertyManager or graphics area to confirm and create the offset entities.

The new offset entities will appear in your 3D sketch, parallel to the original selections at the specified distance.

Practical Considerations for 3D Sketch Offsets

• When offsetting model edges or faces in a 3D sketch, SolidWorks effectively projects that geometry onto a plane or surface relative to the original entity and then creates the offset. This is a powerful way to base 3D sketch geometry on your model's features.
• The direction of the offset in a 3D sketch depends on the original geometry's orientation and the selected direction in the PropertyManager.
• Using the Select Chain option is particularly useful when offsetting complex contours from model edges or faces.

By following these steps, you can effectively use the Offset Entities tool to create parallel geometry within your 3D sketches in SolidWorks.