Full Round & Rule Fillets

Understanding the Basics of Fillet in Fusion

What is a Fillet in CAD Design?

A fillet is a rounded edge that smooths sharp corners on your 3D model. It can improve the look and make parts easier to machine or assemble. Think of the soft edge of a cup or the rounded corner on a car panel—that's a fillet in action.

How to Access and Use the Fillet Command

Fusion offers several fillet options. You can access the command from the toolbar, where you'll see choices for radius, tangent conditions, and more. Picking the right options depends on your design goals—whether you want a simple curve or a precise, continuous bend.

Full Round Fillet: Creating Smooth and Uniform Curves

What is a Full Round Fillet?

A full round fillet creates a smooth, continuous curve along the edges or faces of a model. It maintains a consistent curvature no matter how you change the model's size.

How to Make a Full Round Fillet

1. Click the Fillet command in the Modify menu.

2. Select the full round fillet option.

3. Hover over the face you want to round over and then move near the tangent faces that will connect with it. They will highlight blue. Click to select,

4. Set your radius, such as 30 mm, and press OK.

   
   

Why Use Full Round Fillet?

This type of fillet is perfect when your design needs to keep a uniform, flowing curve. Unlike regular fillets that might break into segments when making larger changes, full round fillets stay smooth, adjusting automatically.

Rule Fillet: Advanced Edge Control and Selective Filleting

What is a Rule Fillet?

Rule fillet is a smarter tool that applies fillets based on rules you set. Instead of manually selecting each edge, you can tell Fusion to fillet certain features or patterns automatically.

Using Rule Fillet Effectively

Imagine creating a series of patterned holes or extrusions. Doing each fillet manually takes forever. Rule fillet saves you time by applying the same settings to multiple features at once.

Here's how:

1. Click the Fillet command in the Modify menu.

2. Choose the rule fillet option.

3. Select the feature you want to add the fillets to, like an extrusion or hole from the timeline.

4. Enter the radius.

5. Decide if you want to fillet just the rounds, just the fillets, or all together.

   
   

Practical Examples

Suppose you have a tapered pattern of extrusions. Instead of selecting each edge individually, use rule fillet and pick the main feature. Then choose “fillets only” or “rounds only” depending on your needs. It applies the fillet everywhere automatically.

In another case, if you have patterned holes, applying rule fillet to the entire pattern saves setting each one separately, especially when the pattern increases in size or complexity.

Managing Complex Scenarios

Sometimes the rule fillet affects parts you don’t want to change. For example, if it fillets more than just edges, you can isolate specific parts by creating separate bodies, then apply rule fillet only to those.

Practical Applications and Real-World Examples

Creating Rounded Edges on Mechanical Parts

For metal brackets, gears, or enclosures, fillets help reduce stress points and improve safety. Full round fillet is ideal for smooth, flowing edges.

Filleting Patterned and Repeated Features

If your project involves patterned holes or extrusions, rule fillet makes quick work of rounding all edges across those features. It’s a huge time saver.

Filleting Intricate and Complex Shapes

For custom or decorative items, full round fillets can transform jagged profiles into smooth, rounded shapes—think pontoons or boat hulls.

Improving Machinability

Fillets make parts easier to machine. Rounded edges reduce tool wear and prevent chipping during manufacturing.