Part Sweep

Overview
The FreeCAD Part Sweep tool (Part Workbench), is used to create a face, shell or a solid shape from two or more profiles, projected along a path.

The Part Sweep tool is similar to Part_Loft with the addition of a path to define the projection between profiles.

The profiles can be a point (vertex), line (Edge), wire or face. Edges and wires may be either open or closed. There are various profile limitations and complications, see below, however the profiles may come from the Part Workbench primitives, Draft Workbench features and a Sketch.

The path can be a line (Edge) or series of connecting lines, wire or various Part Workbench primitives, Draft Workbench features or a Sketch. The path is selected directly from the main model window. The path can either be an entire appropriate shape or an appropriate sub-component of a more advance shape (for example, an edge of a Part Cube could be selected as the path). The path may be either open or closed and will thus create either an open or closed Sweep.

The Sweep has two parameters, "Solid" and "Frenet" each with a value of either "true" or "false", as well as a third parameter "Transition" which describes the transition style of the Sweep at a joint in the path, if the path does not define the corner transition (for example where the path is a wire).

If "Solid" is "true" FreeCAD creates a solid if the profiles are of closed geometry, if "false" FreeCAD creates a face or (if more than one face) a shell for either open or closed profiles.

If "Frenet" is "true" the orientation of the profile will be consistent to the local orientation of the path, along a helical path.

Profile 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 Sweep from a circle to a point, to a ellipse.
 * However you could Sweep from a point to a circle to an ellipse to another point.
 * Open or closed geometry profiles can not be mixed in one single Sweep
 * In one Sweep, all profiles (lines wires etc.) must be either open or closed.
 * For example
 * FreeCAD can not Sweep 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 Sweep
 * 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
 * Circle, Ellipse
 * Regular Polygon
 * Plane (Face)


 * Closed Sweeps
 * The results of closed Sweeps may be unexpected - the Sweep may develop twists or kinks. Sweeping 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.

FreeCAD - Version
0.13 0.14 some of the above is extended functionality added in 0.14