How to Use a Custom Profile for Curve Bevel in Blender

In Blender, creating complex extruded shapes along a curve is fast and flexible using custom bevel profiles. Instead of relying on simple round bevels or using separate objects as bevel targets, Blender features a built-in curve profile widget that lets you design custom cross-sections directly within the curve properties. This guide provides a straightforward, step-by-step process for applying and modifying custom curve bevel profiles to enhance your 3D models.

Step 1: Add or Select a Curve Object

  1. Open your Blender scene.
  2. Press Shift + A, navigate to Curve, and select a curve type (such as Bezier or Nurbs Path).
  3. Select the curve in the 3D Viewport.

Step 2: Open Curve Object Data Properties

  1. Locate the Properties Panel on the right side of the screen.
  2. Click the Object Data Properties icon (represented by a green curve icon).

Step 3: Enable the Custom Bevel Mode

  1. In the Object Data Properties tab, expand the Geometry section.
  2. Scroll down to the Bevel sub-panel.
  3. Under the Mode options, click on Custom.

Step 4: Shape the Custom Profile

Once Custom mode is selected, an interactive curve profile widget appears. You can manipulate this curve widget to dictate the shape of your bevel's cross-section:

  • Add Points: Left-click anywhere on the profile line within the widget to add a new control point.
  • Move Points: Click and drag existing control points to reshape the cross-section.
  • Delete Points: Select a point and press X or click the minus icon next to the widget.
  • Point Corner Types: Toggle between sharp and smooth control points by selecting a point and changing its handle type in the widget controls.
  • Use Presets: Click the Preset dropdown menu above the curve widget to choose pre-made shapes like Support Loops or Cornice.

Step 5: Adjust Resolution and Display Settings

To ensure your custom profile renders smoothly and accurately, tweak the following settings:

  • Resolution C: Controls the density of the bevel geometry along the profile. Higher values create smoother curves but increase polygon count.
  • Fill Caps: Check this box under the Geometry panel if you want to close the open ends of the curve extrusion.
  • Smooth Shading: Under the Normals section of the curve properties, check Auto Smooth or enable smooth shading to render smooth surface transitions.

Converting the Curve to a Mesh (Optional)

If you need to edit the vertices directly or export the model:

  1. Select the curve in Object Mode.
  2. Right-click in the Viewport and select Convert To > Mesh (or go to Object > Convert > Mesh).