How to Create a 3D Solid Using FreeCAD Pad Tool

This guide walks you through the essential process of converting a two-dimensional profile into a three-dimensional solid object using the Pad tool in FreeCAD's Part Design workbench. By learning how to create an active body, sketch a closed profile, and apply extrusion settings, you will master the fundamental modeling operation required for parametric design in FreeCAD.

Step 1: Open FreeCAD and Switch to the Part Design Workbench

  1. Launch FreeCAD and start a new, empty document by selecting File > New or pressing Ctrl + N.
  2. In the workbench selector dropdown menu at the top center of the screen, select Part Design.

Step 2: Create a Body and a New Sketch

  1. In the left-hand panel (Combo View under the Tasks or Model tab), click Create body (or click the blue Body icon on the toolbar).
  2. With the body active, click Create sketch.
  3. A dialog will prompt you to select a base plane. Choose the XY_Plane, XZ_Plane, or YZ_Plane depending on your desired orientation, then click OK. FreeCAD will automatically switch to the Sketcher interface.

Step 3: Draw a Closed 2D Profile

  1. Use the sketching tools (such as Rectangle, Circle, or Polyline) to draw your desired shape.
  2. Ensure the shape is completely closed. The Pad tool will fail if the sketch has disconnected vertices, overlapping lines, or open gaps.
  3. Apply geometric and dimensional constraints to define the shape completely until the sketch turns fully green (fully constrained).
  4. Click Close in the Tasks panel to exit the Sketcher.

Step 4: Apply the Pad Tool

  1. In the tree view, ensure your newly created sketch is selected.
  2. Click the Pad button in the toolbar (represented by a yellow prism being pushed upward) or go to Part Design > Pad.
  3. A 3D preview of your extrusion will immediately appear on the screen, and the Pad parameters will open in the Tasks panel.

Step 5: Adjust Pad Parameters

Configure the extrusion settings in the Tasks panel according to your design needs:

  • Type: Set to Dimension for a standard fixed-depth extrusion.
  • Length: Enter the distance you want to extrude the profile (e.g., 10.00 mm).
  • Symmetric to plane: Check this box if you want the solid to extrude equally in both directions from the sketch plane.
  • Reversed: Check this box to extrude the solid in the opposite direction along the plane's normal axis.

Step 6: Finalize the Solid

Once you have entered your parameters and verified the 3D preview, click OK in the Tasks panel. Your sketch is now transformed into a 3D parametric solid (Pad) inside your Part Design body, ready for further modifications such as pockets, fillets, or additional additive features.