Sketcher ValidateSketch

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Sketcher ValidateSketch

Localização do menu
Sketcher → Validate sketch
Sketcher, PartDesign
Atalho padrão
Veja também


The Validate sketch utility can be used to analyze and repair a sketch that is no longer editable, has invalid constraints, or to add missing coincident constraints to a sketch created from imported geometry such as DXF files. It can also be useful to locate a missing coincidence in a native sketch that generates a "can't validate broken face" error when trying to apply a PartDesign feature.

Sketcher validation tasks pt.png


  1. Select the sketch to validate, either from the Tree view, or by clicking on one of its edges in the 3D view.
    Note: the sketch must not be in editing mode. If you are in sketch edit mode, you need to use the Sketcher LeaveSketch.svg Leave sketch button, or the Close button at the top of the Tasks tab.
  2. Open the validate sketch utility either:
    • from the Sketch → Validate sketch… dropdown
    • pressing the Sketcher ValidateSketch.svg button in the Sketcher_Workbench Sketcher Workbench.
  3. See Options below for operation.
  4. Press the Close button when done.


Missing coincidences

Finds out missing coincidences for overlapping vertices, and adds them. Press the Find button; a pop up dialog will appear to report how many missing coincidences were found; they will be shown in the 3D view as yellow crosses. Press OK to close the dialog, then press the Fix button to add the missing coincidences.

If necessary, define a larger tolerance value in the drop-down field.

Press Highlight open vertexes to highlight vertexes that are outside this tolerance.

This tolerance is also used by the Find/Fix process as well.

Leave the "Ignore construction geometry" checkbox checked to disregard construction geometry in the analysis.

Invalid constraints

Checks for malformed constraints.

For example, if there is a Circle-Line-Tangent constraint, but it references two lines, it is considered invalid.

(This sometimes happens due to the Topological Naming Problem, i.e. the external geometry changes type).

It also does other checks, such as for empty links.

Degenerated geometry

Degenerated geometry can result from solver actions in a sketch.

For instance, if a line is forced to shorten to become almost a point.

Other examples: a zero length line or zero radius circle/arc.

Reversed external geometry

Reversed external geometry can happen because the handling of reversed geometry was changed around revision 0.15.

This process might be helpful if sketches with external-geometry fail to solve because of these changes.

Constraint orientation locking

Tangent and perpendicular constraints are implemented (via-point).

Internally they work by constraining the angle between tangent vectors. With tangent constraint for example, the angle can be 0 or 180 degrees (co-directed or opposed vectors). The actual angle is remembered in the constraint data ("constraint orientation is locked"), it guards against flipping. But the angle can be erased ("constraint orientation unlock") or updated; these tools do exactly that.

The locking mechanism typically works well and this tool should not be needed. It should only used after making a backup of the open document.