freecad-scripts

FreeCAD Scripts

Expert skill for generating production-quality Python scripts for the FreeCAD CAD application. Interprets shorthand, quasi-code, and natural language descriptions of 3D modeling tasks and translates them into correct FreeCAD Python API calls.

When to Use This Skill

• Writing Python scripts for FreeCAD's built-in console or macro system
• Creating or manipulating 3D geometry (Part, Mesh, Sketcher, Path, FEM)
• Building parametric FeaturePython objects with custom properties
• Developing GUI tools using PySide/Qt within FreeCAD
• Manipulating the Coin3D scenegraph via Pivy
• Creating custom workbenches or Gui Commands
• Automating repetitive CAD operations with macros
• Converting between mesh and solid representations
• Scripting FEM analyses, raytracing, or drawing exports

Prerequisites

• FreeCAD installed (0.19+ recommended; 0.21+/1.0+ for latest API)
• Python 3.x (bundled with FreeCAD)
• For GUI work: PySide2 (bundled with FreeCAD)
• For scenegraph: Pivy (bundled with FreeCAD)

FreeCAD Python Environment

FreeCAD embeds a Python interpreter. Scripts run in an environment where these key modules are available:

import FreeCAD          # Core module (also aliased as 'App')
import FreeCADGui       # GUI module (also aliased as 'Gui') — only in GUI mode
import Part             # Part workbench — BRep/OpenCASCADE shapes
import Mesh             # Mesh workbench — triangulated meshes
import Sketcher         # Sketcher workbench — 2D constrained sketches
import Draft            # Draft workbench — 2D drawing tools
import Arch             # Arch/BIM workbench
import Path             # Path/CAM workbench
import FEM              # FEM workbench
import TechDraw         # TechDraw workbench (replaces Drawing)
import BOPTools         # Boolean operations
import CompoundTools    # Compound shape utilities

The FreeCAD Document Model

# Create or access a document
doc = FreeCAD.newDocument("MyDoc")
doc = FreeCAD.ActiveDocument

# Add objects
box = doc.addObject("Part::Box", "MyBox")
box.Length = 10.0
box.Width = 10.0
box.Height = 10.0

# Recompute
doc.recompute()

# Access objects
obj = doc.getObject("MyBox")
obj = doc.MyBox  # Attribute access also works

# Remove objects
doc.removeObject("MyBox")