Sketcher : Requis pour une esquisse

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Revision as of 12:08, 6 November 2019 by Mario52 (talk | contribs) (Created page with "La création d'un corps dans l'espace de travail PartDesign est déjà possible et '''seulement''' à l'aide d'une courbe fermée (profil). La détermination complète de tout...")
Tutoriel
Thème
Modeling
Niveau
Beginner
Temps d'exécution estimé
Auteurs
Maker
Version de FreeCAD
Fichiers exemples
None
Voir aussi
None

Exigences minimales pour un croquis

La création d'un corps dans l'espace de travail PartDesign est déjà possible et seulement à l'aide d'une courbe fermée (profil). La détermination complète de toutes leurs dimensions et propriétés (totalement contrainte) n'est pas encore requise.

That a closed curve is present, is not self-evident and not recognizable. When connecting a circular arc to a straight line, e.g. The two endpoints are created only one above the other. You must use the Point to Point 'tool to make a single point that actually connects the line and the arc.

Sketch

A simple sketch; left: Curve only in four places (red, automatic constraints when drawing with ) closed; Middle: Warning - ... broken face (broken curve); right: Curve closed at remaining four places (green)

However, consistent parametric working means that the sketch is completely determined.

Defining a sketch completely

Even a relatively simple sketch may contain dozens of indeterminacies (indicated in the combo view as a "degrees of freedom" number). To eliminate them together at the end is a relatively confusing task.

Sketch

A simple sketch; completely determined by 25 constraints, of which only 5 are dimension constraints

This work is clearer and simpler if one immediately eliminates the "freedoms" of each added geometric element, i. this dimensions (that is, values for dimensions and placements). The provisional completeness is reached if all lines are displayed in green.

If one waits until the end of the drawing to determine, one finds remaining "freedoms" by touching the points and lines with the mouse pointer and determining where they are not yet fixed. When complete, the entire drawing is displayed in green.

If you accidentally create an 'overmodulation', a warning appears in the combo-view asking you to undo the corresponding actions (constraints).