# Constraint Symmetric

Menyplacering |
---|

Sketch → Sketcher constraints → Constrain symmetrical |

Arbetsbänk(ar) |

Sketcher, PartDesign |

Standard genväg |

None |

Introducerad i version |

- |

Se även |

Constraint Parallel |

## Contents |

## Description

The symmetrical constraint constrains two selected points to be symmetrical around a given line, i.e., both selected points are constrained to lie on a normal to the line through both points and are constrained to be equidistant from the line. Alternatively it can constrain two points to be symmetric with respect to a third one.

## Usage

Select two points (vertexes) in the sketch and a line in the sketch. The selected points and the line will be dark green.

Click on Constrain symmetric or select the Constrain Symmetrical menu item from the Sketcher Constraints sub menu of the Sketcher (or Part Design) menu item.

This will apply the constraint to the selected items.

*Note:* if you want to define a symmetry constraint with respect to a point, the order of the selection is important, depending on if you select the tool at the beginning or at the end.

- If you click the tool first: select the first point, then the symmetry reference point, and finally the second point.
- If you click the tool last: select the first point, then the second point, and finally the symmetry reference point.

See the tracker issue #4144, and forum thread.

**The tools:**New sketch, Edit sketch, Leave sketch, View sketch, View section, Map sketch to face, Reorient sketch, Validate sketch, Merge sketches, Mirror sketch

**Sketcher geometries:**Point, Line by 2 point,**Create an arc,**Arc, Arc by 3 Point,**Create a circle**, Circle, Circle by 3 Point,**Create a conic**, Ellipse by center, Ellipse by 3 points, Arc of ellipse, Arc of hyperbola, Arc of parabola,**Create a B-spline**, Create B-spline, Create periodic B-pline, Polyline (multiple-point line), Rectangle,**Create regular polygon**, Triangle, Square, Pentagon, Hexagon, Heptagon, Octagon, Create Regular Polygon, Slot, Fillet, Trimming, Extend, External Geometry, CarbonCopy, Construction Mode

**Sketcher constraints****Geometric constraints**Coincident, Point On Object, Vertical, Horizontal, Parallel, Perpendicular, Tangent, Equal Length, Symmetric, Constrain Block**Dimensional constraints**Lock, Horizontal Distance, Vertical Distance, Distance, Radius, Internal Angle, Snell's Law, Internal Alignment, Toggle reference/driving constraint,

**Sketcher tools**Select solver DOFs, Close Shape, Connect Edges, Select Constraints, Select Origin, Select Vertical Axis, Select Horizontal Axis, Select Redundant Constraints, Select Conflicting Constraints, Select Elements Associated with constraints, Show/Hide internal geometry, Symmetry, Clone, Copy, Move, Rectangular Array, Delete All Geometry, Delete All Constraints

**Sketcher B-spline tools**Show/Hide B-spline degree, Show/Hide B-spline control polygon, Show/Hide B-spline curvature comb, Show/Hide B-spline knot multiplicity, Convert Geometry to B-spline, Increase degree, Increase knot multiplicity, Decrease knot multiplicity

**Sketcher virtual space**Switch Virtual Space

**Installation:**Linux, Windows, Mac;**Getting started****Basics:**About FreeCAD, Workbenches, Preferences, Document structure, Interface Customization, Properties, Mouse Model; Tutorials**Workbenches**: Arch, Draft, FEM, Image, Inspection, Mesh, OpenSCAD, Part, PartDesign, Path, Plot, Points, Raytracing, Reverse Engineering, Robot, Ship, Sketcher, Spreadsheet, Start, Surface workbench, TechDraw, Test Framework, Web

**Scripting:**Introduction to Python, FreeCAD scripting tutorial, FreeCAD Scripting Basics, How to install macros, Gui Command, Units**Modules:**Builtin modules, Workbench creation, Installing more workbenches**Meshes:**Mesh Scripting, Mesh Module**Parts:**The Part Module, Topological data scripting, PythonOCC, Mesh to Part**Coin scenegraph:**The Coin/Inventor scenegraph, Pivy**Qt interface:**PySide, Using the FreeCAD GUI, Dialog creation**Parametric objects:**Scripted objects**Other:**Code snippets, Line drawing function, Embedding FreeCAD, FreeCAD vector math library, Power users hub, Python, Macros, FreeCAD Scripting Basics, Topological data scripting