Learn about 2D sketching. Discover how to edit a sketch, apply dimensions, and use sketch constraints.
- [Instructor] The sketch is the core of a parametric solid model. Geometric and dimensional constraints control the size of features and make it easy to edit the components. The sketch-based workflow also offers a high degree of flexibility for making significant changes to the model geometry. In Fusion 360, I'll double-click on the sketching component in the Fusion certification project to open it. With the model open, I can close the data panel. Orbiting around the model, I can select any face to begin a sketch on.
From the marking menu, I'll select the sketch tools to create a two point rectangle on the side face. This will bring the face normal to the screen, and I can begin sketching. As I begin sketching, I can start adding dimensions or simply select points to place the rectangle. Once the initial shape is created, I can add dimensions and relate the position of the sketch to the model, entering values to make updates.
I can also use other sketch geometry to create relationships such as drawing a line from the midpoint of the edge to the midpoint of one of the lines. Then applying a geometric constraint such as perpendicular, to center the rectangle on the face. To avoid causing confusion when creating a feature, I can select any sketch geometry and toggle it to be construction geometry. This geometry will be ignored by 3D features.
When I'm done with the sketch, I can select stop sketch from the sketch palette or from the toolbar. In this model, there were already two other sketches. One that defines the profile on the top, and the second that defines the overall shape. With a double-click either in the timeline or by expanding the browser and selecting the first sketch from the timeline, I can bring it back up. The sketch geometry is blue which indicates that it's under-constrained.
So clicking on an edge or a point allows me to move it. In some cases, in ways I really don't want to be able to. I can either undo or I can start applying sketch constraints to control this. In this sketch palette are all of the constraints that are available based on the geometry selected. So with this point selected, you'll see constraints such as tangent or smooth are not available. By clicking on any open part of the canvas, I'll remove the selection and then be able to select tools like the horizontal, vertical constraint which I'll apply to this line.
Now because the line is horizontal and the length is specified, it's turned black. So this edge is fully defined. I'll add a perpendicularity constraint to this edge and it will turn black as well as the top. Now I'd like to apply some dimensional constraints. From the marking menu, I can select the sketch dimension tool, select an edge, set the value, and now the only thing I have to constrain is this top edge.
I'll set the width of this top edge, and I'll tell it that I'd like it to be the same as this height divided by two. Now my sketch is fully constrained. But I'd like to add some more detail to it. I'll start the line tool and begin sketching, adding more geometry to my model. If I leave it like this, I can come back and select this profile for an additional feature. However, if I use the trim tool, so I make a continuous profile, it will update the model as is.
I'll leave this under constrained for now as I'm not sure of what size we need. And I'll stop the sketch. When the model returns, you see the new feature added based on the new profile of the sketch. Sketch definition and control is often an overlooked area to develop skills, but it's a great place to practice different techniques.
- Considerations for becoming certified
- Tips for taking the exam
- Creating a project
- Creating a 2D sketch
- Creating extrude features and revolve features
- Working with direct modeling
- Understanding assembly structure
- Creating drawing views
- Working with advanced modeling tools
- Generating data for 3D printing
- Performing a stress analysis