Part Module

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Revision as of 13:17, 19 November 2020 by Roy 043 (talk | contribs) (Part_Union -> Part_Fuse)
Part workbench icon

Introduction

The solid modelling capabilities of FreeCAD are based on the OpenCASCADE Technology (OCCT) kernel, a professional-grade CAD system that features advanced 3D geometry creation and manipulation. The Part Workbench is a layer sitting on top of the OCCT libraries, that gives the user access to OCCT geometric primitives and functions. Essentially all 2D and 3D drawing functions in every workbench ( Draft, Sketcher, PartDesign, etc.), are based on these functions exposed by the Part Workbench. Therefore, the Part Workbench is considered the core component of the modelling capabilities of FreeCAD.

The objects created with the Part Workbench are relatively simple; they are intended to be used with boolean operations (unions and cuts) in order to build more complex shapes. This modeling paradigm is known as the constructive solid geometry (CSG) workflow, and it was the traditional methodology used in early CAD systems. On the other hand, the PartDesign Workbench provides a more modern workflow to constructing shapes: it uses a parametrically defined sketch, that is extruded to form a basic solid body, which is then modified by parametric transformations (feature editing), until the final object is obtained.

Part objects are more complex than mesh objects created with the Mesh Workbench, as they permit more advanced operations like coherent boolean operations, modifications history, and parametric behaviour.

The Part Workbench is the basic layer that exposes the OCCT drawing functions to all workbenches in FreeCAD.

Tools

The tools are located in the Part menu or the Measure menu.

Primitives

These are tools for creating primitive objects.

  • Box: Draws a box by specifying its dimensions
  • Cylinder: Draws a cylinder by specifying its dimensions
  • Sphere: Draws a sphere by specifying its dimensions
  • Cone: Draws a cone by specifying its dimensions
  • Torus: Draws a torus (ring) by specifying its dimensions
  • Tube: draws a tube by specifying its internal radius and external radius. introduced in version 0.19
  • Primitives: A tool to add any of the defined geometric primitives.
  • Builder: A tool to create more complex shapes from various parametric geometric primitives

Modifying objects

These are tools for modifying existing objects. They will allow you to choose which object to modify.

  • Extrude: Extrudes planar faces of an object
  • Revolve: Creates a solid by revolving another object (not solid) around an axis
  • Mirror: Mirrors the selected object on a given mirror plane
  • Fillet: Fillets (rounds) edges of an object
  • Chamfer: Chamfers edges of an object
  • Ruled Surface:
  • Loft: Lofts from one profile to another
  • Sweep: Sweeps one or more profiles along a path
  • Thickness: Hollows out a solid, leaving openings next to select faces.
  • Boolean: Performs boolean operations on objects
  • Fuse: Fuses (unions) two objects
  • Cut: Cuts (subtracts) one object from another
  • Common: Extracts the common (intersection) part of two objects

Measure

File:Part Measure Menu.png Measure: Allows linear and angular measurement between points, edges, and faces.

Other tools

Context menu items

  • Appearance: determines appearance of the whole part (color transparency etc.).
  • Set colors: assigns colors to part faces.

Preferences

  • Preferences: preferences available for Part Tools (the Part workbench also uses the PartDesign Preferences).
  • Import Export Preferences: preferences available for importing from and exporting to different file formats.
  • Fine-tuning: some extra parameters to fine-tune Part behavior.

Scripting

See Part scripting.

Tutorials