TIL - Creating Rounded Rectangles in FreeCAD's Sketcher

28 Nov, 2024

Adding Rounded Corners to an Existing Rectangle

1. Draw the rectangle:

   • Create a rectangle with the desired dimensions (e.g., 25mm × 25mm).

2. Round the corners:

   • Use the Fillet tool to round all four corners by applying a consistent radius (e.g., 3mm).

3. Apply constraints:

   • Set equal constraints to ensure all four arc fillets are identical.
   • Define the desired radius dimension for the corners.

4. Verify tangent constraints:

   • Ensure tangent constraints are correctly applied between the arcs and the straight lines.

Rounded Rectangle Creation Tool

1. Select the Sketcher workbench.
2. Use the rectangle tool:
   • Click the Create a rectangle tool in the Sketcher toolbar.
3. Enable rounded corners:
   • In the Rectangle parameters section (at the top of the Sketcher dialog), check the Rounded corners checkbox.
4. Define dimensions:
   • Click to place the first corner of the rectangle.
   • Click again to set the opposite corner, defining the rectangle’s size.
   • Set the fillet radius for all corners either by clicking or entering a value.