Part Loft/fr

Présentation
L'outil FreeCAD Lissage (Atelier Part), est utilisé pour créer une face, une coquille ou une forme solide à partir de deux ou plusieurs profils. Les profils peuvent être un point (sommet), ligne (Arête), un fil ou une face. Arêtes et fils peuvent être soit ouverts ou fermés. Il existe différents limites et complications, voir ci-dessous, mais les profils peuvent provenir des primitives de l'atelier Part (Pièce), des traits de l'atelier Draft(planche à dessin) et d'un Sketch (esquisse)

Le Lissage a trois paramètres,"Exclu", "Solide" et "Fermé" chacun avec une valeur soit"true" (vrai)ou "false" (faux).

Si "Exclu"est "true" FreeCAD crée une face, des faces ou un solide depuis les surfaces exclues.Ruled surface page on Wikipedia.

Si "Solid" est "true" FreeCAD crée un solide si les profils sont une géométrie fermée, si "false" FreeCAD crée une face ou(si plus d'une face) une coque pour soit des profils ouverts ou fermés.

Si "Closed" est "true" FreeCAD essaye de lisser le dernier profil vers le premier profil pour créer une figure fermée

Pour plus d'informations sur la façon dont les profils sont réunis, consultez la page Lissage Détails techniques page.



Limitations and complications

 * A vertex or point
 * vertex or point may only be used as the first and/or last profile in the list of profiles.
 * For example
 * you can not loft from a circle to a point, to a ellipse.
 * However you could Loft from a point to a circle to an ellipse to another point.
 * Open or closed geometry profiles can not be mixed in one single Loft
 * In one Loft, all profiles (lines wires etc.) must be either open or closed.
 * For example
 * FreeCAD can not Loft between one Part Circle and one default Part Line.
 * Draft Workbench features
 * Draft Workbench features can be directly used as a profile in FreeCAD 0.14 or later.
 * For example the following Draft features can be used as profiles in a Part Loft
 * Draft Polygon.
 * Draft Point, Line, wire,
 * Draft B-spline, Bezier Curve
 * Draft Circle, Ellipse, Rectangle
 * PartDesign Sketches
 * The profile may be created with a sketch. However only a valid sketch will be shown in the list to be available for selection.
 * The sketch must contain only one open or closed wire or line (can be multiple lines, if those lines are all connected as they are then a single wire)
 * Part Workbench
 * the profile can be a valid Part geometric primitive which can be created with the Part CreatePrimitives tool
 * For example the following Part geometric primitives can be a valid profile
 * Point (Vertex), Line (Edge)
 * Helix, Spiral
 * Circle, Ellipse
 * Regular Polygon
 * Plane (Face)


 * Closed Lofts
 * The results of closed lofts may be unexpected - the loft may develop twists or kinks. Lofting is very sensitive to the Placement of the profiles and the complexity of the curves required to connect the corresponding Vertices in all the profiles.

An example Loft
The Loft tool is in the Part Workbench, menu Part -> Loft... or via the icon in the tool bar.



In the "Tasks" will be two lists: "node / wire" and "free form".



Selection of the elements
In the "node / wire" the available items are displayed. Two elements must be selected one after the first in this list.



Thereafter, with the blue arrow that item is added to the list of "free form".



The selected items must be of the same type, so.

Tip: the active / selected items in the list are displayed in the 3D area as active / selected.

Command complete
If both elements are selected, the command can be completed with "OK".



Result
From closed lines arise surfaces which might be taken at a superficial look for solids / solids.



If indeed a solid / solid to be created, can be used either when you create the button "Create Solid" or after creating the field properties tab data created the free-form surface of the switch "Solid" by pop be set to "true" / set properly.

The procedure is analogous open polylines.

FreeCAD Version

 * added Version 0.13
 * "closed" property added Version 0.14
 * Ability to use a face as a profile added Version 0.14