How to Create a Polar Array in FreeCAD

This guide explains how to create a polar array of features around a central axis in FreeCAD using the Part Design workbench. By utilizing the Polar Pattern tool, you can quickly replicate 3D features—such as holes, pockets, pads, or slots—in a circular distribution. The following steps cover feature selection, axis designation, and configuration of spacing and instance counts.

Step 1: Open the Part Design Workbench

  1. Open your project in FreeCAD.
  2. Ensure your active body contains the base geometry and the specific feature (e.g., a Pad, Pocket, or Hole) you want to duplicate.
  3. Switch to the Part Design workbench via the workbench dropdown menu.

Step 2: Select the Feature to Replicate

  1. In the Model tree view, click on the feature you wish to pattern.
  2. Alternatively, you can select a face of the feature directly in the 3D view.

Step 3: Launch the Polar Pattern Tool

  1. With the feature selected, click the Create a polar pattern feature icon in the Part Design toolbar (represented by multiple yellow cubes arranged in a circle).
  2. Alternatively, navigate to the top menu and select PartDesign > Apply a pattern > PolarPattern.
  3. The Tasks tab will open on the left panel showing the pattern parameters.

Step 4: Define the Axis of Rotation

In the Tasks panel under Axis:

  • Standard Axes: Select Base Z axis, Base X axis, or Base Y axis if your model is centered around the global coordinate system.
  • Custom Reference: Choose Select reference... and click on an existing cylindrical face, circular edge, or a pre-defined Datum Line in the 3D view to use it as the center of rotation.

Step 5: Configure Pattern Parameters

  1. Occurrences: Set the total number of instances you want in the array (this count includes the original feature).
  2. Angle: Set the total angle coverage for the pattern. Use 360° for a full circle, or a smaller angle (e.g., 180° or 90°) for a partial arc.
  3. Reverse Direction: Check this box if you need the pattern to sweep in the opposite angular direction.

Step 6: Confirm and Finalize

  1. Review the preview in the 3D viewport to ensure the positioning is correct.
  2. Click OK in the Tasks panel to generate the polar array.

The new PolarPattern object will now appear in your tree view nested under the active Body. You can double-click it at any time to modify the number of occurrences, the angle, or the rotation axis.