Create a Polar Array of Columns in FreeCAD

Creating a circular arrangement of architectural columns in FreeCAD is a straightforward process that combines the BIM (or Arch) Workbench with the Draft Workbench. This guide walks you through modeling an initial column, positioning it relative to a central rotation point, and applying the Draft Polar Array tool to generate evenly spaced duplicates around a full or partial circle.

Step 1: Create the Base Column

  1. Open FreeCAD and create a new document.
  2. Switch to the BIM Workbench (or Arch Workbench in older FreeCAD versions).
  3. Click the Column tool to place an architectural column into your 3D view.
  4. Select the newly created column in the Tree view and use the Data tab in the Property panel to set its dimensions, such as Height, Length, and Width (or diameter if using a circular profile).

Step 2: Offset the Column from the Center

The Polar Array tool rotates objects around a center point (defaulting to the origin: (0, 0, 0)). To set the radius of your circular array:

  1. Select the column in the Tree view.
  2. In the Data tab, expand the Placement property, then expand Base.
  3. Set the X or Y coordinate to your desired radius (for example, set X = 3000 mm to place the column 3 meters away from the center). Leave the center point at (0, 0, 0).

Step 3: Generate the Polar Array

  1. Switch to the Draft Workbench.
  2. Select your column in the Tree view.
  3. Click the Array dropdown menu in the toolbar and select Polar Array (or click the dedicated Polar Array icon).
  4. A dialog or task panel may appear prompting you to enter settings, or it will generate a default array immediately:
    • Polar Angle: Set the total span of the circle (enter 360 for a complete circular layout).
    • Number of Elements: Enter the total number of columns you want in the array.
    • Center: Set the coordinates around which the array rotates (usually (0, 0, 0)).

Step 4: Fine-Tune the Array Properties

Once created, the array remains fully parametric. You can modify it at any time:

  1. Select the Array object in the Tree view.
  2. In the Data tab below, locate the array properties:
    • Number Polar: Change the total count of columns.
    • Interval Angle: Adjust the angle spacing if using custom increments.
    • Axis: Ensure the rotation axis is set to the Z-axis ((0, 0, 1)) for horizontal circular arrangements.
  3. If you edit the dimensions of the original column inside the array, all instances will update automatically.