How Do You Fillet Two 3D Objects in AutoCAD?

AutoCAD is a powerful software tool used by architects, engineers, and designers to create precise 2D and 3D models. One essential feature of AutoCAD is the ability to fillet or round the edges of 3D objects. In this tutorial, we will explore how to fillet two 3D objects in AutoCAD.

Understanding Filleting in AutoCAD

Filleting is the process of creating a smooth transition between two intersecting lines or curves. It helps to remove sharp edges and corners, giving your design a more polished and professional look.

AutoCAD offers different fillet commands for different types of objects. In this tutorial, we will focus on filleting 3D objects.

Filleting Two 3D Objects

To fillet two 3D objects in AutoCAD, follow these steps:

  1. Select the Fillet Command: To start the fillet command, type FILLET in the command line or select it from the Modify panel in the Home tab.
  2. Select First Object: After activating the fillet command, you need to select the first object that you want to fillet. This can be a line, polyline, arc, or other compatible objects.
  3. Select Second Object: Once you have selected the first object, AutoCAD prompts you to select the second object. Choose another object that intersects with the first one.
  4. Set Fillet Radius: After selecting both objects, you need to define the fillet radius. The radius determines how much material should be removed from each object’s corner to create a smooth transition.

    You can specify a radius value or use the Distance option to set the fillet length.

  5. Preview and Adjust: AutoCAD provides a preview of the filleted objects before applying the changes. You can adjust the fillet radius or select different objects if needed.
  6. Create Fillet: Once you are satisfied with the preview, click on Create or press Enter to apply the fillet. AutoCAD will round the selected corners and create a smooth transition between the two objects.

Note: You can use the Fillet command multiple times to fillet multiple pairs of objects without exiting the command. Simply repeat steps 2 to 6 for each pair of objects you want to fillet.

Tips for Filleting in AutoCAD

To ensure successful filleting in AutoCAD, consider these tips:

  • Object Selection: Make sure you select compatible objects that intersect each other. The fillet command won’t work if there is no intersection between the chosen objects.
  • Fillet Radius: Experiment with different radius values until you achieve your desired result. Smaller radii will create sharper curves, while larger radii will produce smoother transitions.
  • Fillet Preview: Take advantage of AutoCAD’s preview feature to visualize how your design will look after applying the fillet.

    This helps you make better decisions and avoid unnecessary modifications later on.

  • Fillet Options: AutoCAD offers additional options like Trim and Multiple. These options allow you to trim overlapping parts and apply multiple fillets simultaneously, respectively. Explore these options for more control over your designs.


Filleting two 3D objects in AutoCAD is a straightforward process that can significantly enhance the aesthetics of your designs. By following the steps outlined in this tutorial and considering the provided tips, you can easily create smooth transitions between intersecting objects. Remember to experiment with different fillet radii to achieve your desired results.

So go ahead, practice filleting in AutoCAD, and take your designs to the next level!