Sketcher External: Difference between revisions

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The [[Image:Sketcher_External.svg|16px]] [[Sketcher_External| Sketcher External]] tool adds a linked construction geometry into the sketch to apply constraints between sketch geometry and something outside the sketch. The default colour of externally linked edges is magenta. As with standard non-linked construction geometry (blue), the externally linked geometry is only visible when the sketch is in edit mode and is not directly used in the subsequent result from use of the sketch in another tool. Both types of construction geometry may be used as a reference for constraints within the sketch.
The [[Image:Sketcher_External.svg|24px]] [[Sketcher_External|Sketcher External]] tool projects edges and/or vertices belonging to objects outside the sketch onto the sketch plane. The projected geometry is called "external geometry". It stays parametrically linked to its source objects. External geometry edges are marked with a special color (default magenta) and ({{Version|0.22}}) linetype. External geometry is not visible outside the sketch, it is intended to help define constraints and other sketch geometry. In that sense it is similar to construction geometry.

External geometry (default colour magenta) lines are similar (default colour blue) [[Sketcher_ToggleConstruction|Contruction lines]] except in that the external geometry magenta lines are parametrically linked back to an element of the solid to which the sketch is mapped.
Construction geometry are lines that are internal to the sketch, are only visible when the sketch is in edit mode and will be used for constraint references only, and not directly for later solid operations, like Pad or Pocket.

The external geometry can, for example, be used as a reference for a constraint being used to position a hole in an object at a specific location relative to an edge or vertex.


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Revision as of 10:20, 23 March 2024

This documentation is a work in progress. Please don't mark it as translatable since it will change in the next hours and days.

Sketcher External

Menu location
Sketch → Sketcher geometries → Create external geometry
Workbenches
Sketcher
Default shortcut
G X
Introduced in version
-
See also
Sketcher ConstructionMode

Description

The Sketcher External tool projects edges and/or vertices belonging to objects outside the sketch onto the sketch plane. The projected geometry is called "external geometry". It stays parametrically linked to its source objects. External geometry edges are marked with a special color (default magenta) and (introduced in version 0.22) linetype. External geometry is not visible outside the sketch, it is intended to help define constraints and other sketch geometry. In that sense it is similar to construction geometry.

Usage

See also: Drawing aids.

  1. Create a new sketch, or open an existing sketch.
  2. There are several ways to invoke the tool:
    • Press the Create external geometry button.
    • Select the Sketcher → Sketcher geometries → Create external geometry option from the menu.
    • Right-click in the 3D view and select the Create external geometry option from the context menu.
    • Use the keyboard shortcut: G then X.
  3. The cursor changes to a white cross with the current tool icon.
  4. Pick edges and/or vertexes to project and link them onto in the sketchplane.

Notes

A note of caution, using this tool to link to generated (solid) geometry can lead to unexpected results due to Topological Naming Problem. Also see Advice for stable models.

  • Only edges and vertices from objects from same coordinate system are allowed.

That is, the sketch and the object must be in same Body (when in Part Design workbench), or in same Part (when in Part workbench), or both outside of any Parts and Bodies.

For example, If the open sketch is in Body, you can use another sketch from Body as external geometry, but you can't use a sketch from Body001, or an edge from a Part Cube in the root of the project. Use Shapebinder feature to bring in a copy of the object into the coordinate system of open sketch. Then you will be able to use edges/vertices of Shapebinder object.

  • No circular dependencies are allowed.

That means, you can't link to Pocket made with this sketch. You can't link to any object that depends on the sketch.

Sketch doesn't have to be on any face in order to use this tool. Links directly between sketches are possible, and encouraged, as they are more reliable.

Example

This, below, is a sketch mapped to the top face of a solid created from a Pad of a previous sketch. The magenta lines are External Geometry linked to two edges of this pre-existing Pad.

In this case they are used as a reference for tangency constraints with the circumferences of one circle. They are also used as the reference for a horizontal and a vertical constraint to locate the centre of the second circle relative to the end and top of the Pad.

This is the same sketch in edit mode, with the Pad upon which it is mapped hidden.

When the sketch edit mode is closed, external Geometry lines are not visible.