TechDraw LinkDimension

VerticalExtentDimension

Balloon

TechDraw

The TechDraw LinkDimension tool is DEPRECATED and will be removed in a future version. It should only be used with old (< v0.19) FreeCAD versions and files.
In newer versions the TechDraw DimensionRepair tool should be used to change both 2D and 3D references.

TechDraw LinkDimension
Menu location
TechDraw → Dimensions → Link Dimension to 3D Geometry
Workbenches
TechDraw
Default shortcut
None
Introduced in version
-
See also
TechDraw View, TechDraw ProjectionGroup

Description

The TechDraw LinkDimension tool creates a link between 3D geometry and one or more existing projected Dimensions on a Page. This link allows the Dimension to use actual 3D values instead of 2D projected values.

The Link Dimension tool's most common use is in dimensioning isometric views in a ProjectionGroup. The projected length of an Edge in an isometric view will, of course, not necessarily equal the actual length of the Edge. In an orthogonal view the projected and actual lengths will be equal.

The link instructs the Dimension to compute it's value directly from the 3D geometry.

Usage

1. Create an appropriate dimension on the drawing page using any of TechDraw LengthDimension, TechDraw HorizontalDimension, etc. This dimension will be in the right place on the Page, but will show the projected dimension value.
2. Select the geometry in the 3D view, for example, an edge, that corresponds to the projected geometry of your dimension.
3. There are several ways to invoke the tool:
   • Press the Link Dimension to 3D Geometry button.
   • Select the TechDraw → Dimensions → Link Dimension to 3D Geometry option from the menu.
4. A task panel opens.
5. Select one or more Dimensions to be linked to the selected 3D geometry.
6. Press OK.

The link operation changes the DataMeasureType property of the dimension from Projected to True.

Limitations

Dimension objects are vulnerable to the "topological naming problem". See TechDraw LengthDimension for more information. It is recommended that linking dimensions be one of the last steps in your drawing process.

The link tool will not stop you from making illogical links, so you need to choose the correct edge from the 3D view when creating the link.

There is currently no way to break a link; you can change the DataMeasureType back to Projected so that the dimension will use the projected value instead of the linked value.

Note that if the Dimension to be linked is based on two vertices, you should select two vertices in the 3D view. Similarly if the Dimension is based on an edge, you should select an edge in the 3D view.

Scripting

See also: Autogenerated API documentation and FreeCAD Scripting Basics.

The TechDraw LinkDimension tool is not directly usable in macros, but changing the DataReferences 3D property can accomplish the same result.

VerticalExtentDimension

Balloon

TechDraw

TechDraw

• Pages: Insert Default Page, Insert Page using Template, Redraw Page, Print All Pages
• Views: Insert View, Insert Active View, Insert Projection Group, Insert Section View, Insert Complex Section View, Insert Detail View, Insert Draft Workbench Object, Insert Arch Workbench Object, Insert Spreadsheet View, Insert Clip Group, Share View, Project Shape
• Stacking: Move view to top of stack, Move view to bottom of stack, Move view up one level, Move view down one level

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• Decorations: Hatch Face using Image File, Apply Geometric Hatch to Face, Insert SVG Symbol, Insert Bitmap Image, Turn View Frames On/Off
• Dimensions: Insert Length Dimension, Insert Horizontal Dimension, Insert Vertical Dimension, Insert Radius Dimension, Insert Diameter Dimension, Insert Angle Dimension, Insert 3-Point Angle Dimension, Insert Horizontal Extent Dimension, Insert Vertical Extent Dimension, Link Dimension to 3D Geometry, Insert Balloon Annotation, Insert Axonometric Length Dimension, Insert Landmark Dimension, Adjust Geometric References of Dimension
• Annotations: Insert Annotation, Add Leaderline to View, Insert Rich Text Annotation, Add Cosmetic Vertex, Add Midpoint Vertices, Add Quadrant Vertices, Add Centerline to Faces, Add Centerline between 2 Lines, Add Centerline between 2 Points, Add Cosmetic Line Through 2 points, Add Cosmetic Circle, Change Appearance of Lines, Show/Hide Invisible Edges, Add Welding Information to Leader, Add Surface Finish Symbol, Add Hole or Shaft Tolerances

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• Extensions:
  • Attributes and modifications: Select Line Attributes, Cascade Spacing and Delta Distance, Change Line Attributes, Extend Line, Shorten Line, Lock/Unlock View, Position Section View, Position Horizontal Chain Dimensions, Position Vertical Chain Dimensions, Position Oblique Chain Dimensions, Cascade Horizontal Dimensions, Cascade Vertical Dimensions, Cascade Oblique Dimensions, Calculate the area of selected faces, Calculate the arc length of selected edges, Customize format label
  • Centerlines and threading: Add Circle Centerlines, Add Bolt Circle Centerlines, Add Cosmetic Thread Hole Side View, Add Cosmetic Thread Hole Bottom View, Add Cosmetic Thread Bolt Side View, Add Cosmetic Thread Bolt Bottom View, Add Cosmetic Intersection Vertex(es), Add an offset vertex, Add Cosmetic Circle, Add Cosmetic Arc, Add Cosmetic Circle 3 Points, Add Cosmetic Parallel Line, Add Cosmetic Perpendicular Line
  • Dimensions: Create Horizontal Chain Dimensions, Create Vertical Chain Dimensions, Create Oblique Chain Dimensions, Create Horizontal Coordinate Dimensions, Create Vertical Coordinate Dimensions, Create Oblique Coordinate Dimensions, Create Horizontal Chamfer Dimension, Create Vertical Chamfer Dimension, Create Arc Length Dimension, Insert '⌀' Prefix, Insert '〼' Prefix, Remove Prefix, Increase Decimal Places, Decrease Decimal Places

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• Export: Export Page as SVG, Export Page as DXF
• Additional: Line Groups, Templates, Hatching, Geometric dimensioning and tolerancing, Preferences

User documentation

• Getting started
• Installation: Download, Windows, Linux, Mac, Additional components, Docker, AppImage, Ubuntu Snap
• Basics: About FreeCAD, Interface, Mouse navigation, Selection methods, Object name, Preferences, Workbenches, Document structure, Properties, Help FreeCAD, Donate

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• Help: Tutorials, Video tutorials
• Workbenches: Std Base, Arch, Assembly, CAM, Draft, FEM, Inspection, Mesh, OpenSCAD, Part, PartDesign, Points, Reverse Engineering, Robot, Sketcher, Spreadsheet, Start, Surface, TechDraw, Test Framework, Web

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• Addons: Addon Manager, External workbenches, Scripting and macros

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• Hubs: User hub, Power users hub, Developer hub