Make Complex Shapes in Fusion – Twisted Bracket with 3D Sketches
Autodesk Fusion, formerly known as Fusion 360, is a powerful CAD tool that allows users to create precise 3D models with ease. In this tutorial, we’ll walk through the process of designing a twisted bracket using key solid modeling tools. The full video tutorial is available at the end of this post.
Step 1: Creating a New Component
The first rule of Fusion—always create a new component. For this project, I’m choosing a sheet metal component to highlight this option, though we won’t dive into sheet metal workflows here. You’ll notice its unique symbol in the project browser.
Step 2: Starting with a 2D Sketch
As with most Fusion workflows, we start with a 2D sketch to drive the 3D geometry. A center rectangle keeps the sketch centralized above the origin, making it easy to maintain symmetry. The dimensions, 25 mm by 20 mm, are just for this tutorial, but feel free to experiment.
Step 3: Extruding the Sketch
No time wasted—we jump straight from the sketch to the Extrude command, giving this part of the bracket a height of 5 mm.
Step 4: Adding Fillets for Strength and Aesthetics
Fillets aren’t just for looks—they enhance aesthetics, improve user experience, and even strengthen a design. With a 20 mm long side, a 10 mm fillet on each end creates a smooth, rounded look.
Step 5: Creating a Hole in the Bracket
For this tutorial, I’m using a simple circle for the hole, but if you want more advanced options, the Hole command is worth exploring. The diameter is set to 7.5 mm, but in a real manufacturing scenario, I’d research the optimal size. To ensure the hole updates dynamically, I switch the extent type from 'Distance' to 'All' so it always cuts through the entire bracket.
Step 6: Rotating the Body
Now comes the fun part—creating rotations. Make sure to check the 'Create Copy' box before selecting the body to rotate it around its own axis without shifting position. This creates a copy within the component, but if you need more flexibility, consider copying the component or using user parameters.
Step 7: Connecting the Ends with a 3D Sketch
To build the bridge between the ends of the twisted bracket, we activate 3D Sketch. Though it’s not needed for the first line, it’s essential for the spline.
Sketches in this step serve as guides, not final geometry, so we turn them into construction geometry. The first line connects the central parts of each end, and Fusion helps identify key geometrical points for precision.
Step 8: Using a Fit Point Spline for Precision
Why use a spline instead of a straight line? Simple—by using the edges of the twisted bracket along with a tangent constraint, we control the spline’s curvature precisely. This keeps the shape clean and balanced with minimal effort.
Step 9: Sweeping the Profile with Path + Guide Rail
With the sketch finalized, we use the Sweep tool to create the solid form. It’s crucial to set the type to Path + Guide Rail. Select the profile, then the path, and finally the guide rail in that order. As soon as all three are selected, the new solid appears instantly, giving us the desired twisted shape.
Final Touches
Everything looks great, especially considering we’ve shaped this complex form in just over four minutes. Now, all that’s left is refining the appearance. Fusion makes it easy to experiment with colors and materials to enhance the final look.
Watch the Full Video
For a complete step-by-step breakdown, watch the full video tutorial below. If you have any questions or want to see more advanced workflows, let me know in the comments!
Happy modeling!