Changing the coordinate system in a SolidWorks 3D sketch is straightforward: you can shift the sketch plane or orientation by interacting with existing geometry or defined coordinate systems while selecting a sketch tool.
Understanding 3D Sketch Coordinate Systems
When you start a 3D sketch in SolidWorks, the default coordinate system typically aligns with the global origin and standard planes (Front, Top, Right). However, for complex geometry or specific design intent, you might need to align your sketching with a different orientation or location in 3D space. This is where changing the coordinate system comes into play.
This process doesn't create a new sketch coordinate system in the traditional sense, but rather defines the active sketch plane and orientation for the specific sketch tool you are currently using within the 3D sketch environment.
Steps to Change the Sketch Plane Orientation
According to the SolidWorks documentation, the method to change the coordinate system (or more accurately, the active sketch plane) for a specific tool within your 3D sketch is as follows:
- Start a 3D Sketch: First, ensure you are in an active 3D sketch session. You can do this by going to
Sketch > 3D Sketchor using the Sketch tab on the CommandManager. - Select a Sketch Tool: Choose the sketch entity you want to draw (e.g.,
Line,Circle,Rectangle). Do not click in the graphics area yet to place the entity. - Hold Down the Ctrl Key: Before selecting where you want to place the sketch entity, press and hold the
Ctrlkey on your keyboard. - Click the Target Reference: While holding
Ctrl, click on one of the following references in your graphics area:- A plane (e.g., Front Plane, Top Plane, Right Plane, or a custom reference plane).
- A planar face on an existing solid body.
- A user-defined coordinate system (CSYS) you have previously created.
Once you click the reference while holding Ctrl, SolidWorks will orient the sketch tool's plane to that reference. You can then proceed to sketch your entity on that newly defined active plane within your 3D sketch. The orientation axes (often represented by red, green, and blue arrows) will update to reflect the new sketching plane.
Key takeaway from the reference: To change the coordinate system for your 3D sketch, click the required sketch tool, hold down the Ctrl key, and click a plane, a planar face, or a user-defined coordinate system.
Practical Applications
Changing the active sketch plane in a 3D sketch is useful for:
- Sketching entities precisely on the surface of a complex model.
- Defining features that are offset or angled relative to standard planes.
- Working within a specific local coordinate system defined for a particular part of your design.
For example, if you need to draw a circle directly on a slanted face of your model in a 3D sketch, you would select the Circle tool, hold Ctrl, and click that slanted face. SolidWorks would then orient the circle tool to lie on that face's plane.
Summary Table
| Action | Result |
|---|---|
| Start 3D Sketch | Enter 3D sketching mode. |
| Select Sketch Tool (e.g., Line, Circle) | Prepare to draw a specific entity. |
| Hold Ctrl Key | Signal intent to select a reference plane/orientation. |
| Click Plane, Planar Face, or User CSYS | Define the active sketching plane/orientation for the tool. |
| Proceed with Sketching | Draw the entity on the newly defined active plane. |
By following these steps, you can effectively control the orientation of your sketch entities within the versatile environment of a SolidWorks 3D sketch.
