![]() Both Draft and Sketcher can be used for 2D geometry drawing, and 3D solid creation, although their preferred use is different the Sketcher is normally used together with the Part and PartDesign workbenches to create solids Draft is normally used for simple planar drawings over a grid, as when drawing an architectural floor plan in these situations Draft is mostly used together with the Arch Workbench. Unlike Sketcher elements, Draft objects don't use constraints they are simple shapes defined at the moment of creation. If you only need to produce 2D views for print, and don't want to create 3D models, check out the Draft workbench. Constraints are only visible in Sketch edit mode. Once sketches are used to generate a solid feature, they are automatically hidden. The Sketcher is not intended for producing 2D blueprints. ![]() They are detailed in the 'Tools' section below. There are two kinds of constraints: geometric and dimensional. A complex Sketch with multiple objects will have a number of different solutions, and making it fully-constrained means that just one of these possible solutions has been reached based on the applied constraints. A line can be tangent to an arc or a circle, and so on. An angle can be set between them, or they can be set perpendicular. Two lines can be joined through one of their points with the coincident point constraint. Multiple objects can be constrained between one another. The line is then considered fully-constrained. And applying a dimension constraint will remove the last degree of freedom. Locking one of its points in relation to the origin will remove another 2 degrees of freedom. For example, a line without constraints has 4 Degrees Of Freedom (abbreviated as "DOF"): it can be moved horizontally or vertically, it can be stretched, and it can be rotated.Īpplying a horizontal or vertical constraint, or an angle constraint (relative to another line or to one of the axes), will limit its capacity to rotate, thus leaving it with 3 degrees of freedom. Instead of dimensions, Constraints are used to limit the degrees of freedom of an object. This gives great flexibility in the design process. ![]() They are in effect "floating" and can be moved, stretched, rotated, scaled, and so on. Objects can be drawn loosely, and as long as they are unconstrained, can be modified. Objects do not need to be drawn exactly as you intend to, because they will be defined later on by constraints. ![]() When you've finished drawing your geometries, you add dimensions to them. Or you will draw your line without regard to its position, and move it afterwards. If you want to draw an horizontal line 100mm in length starting at (0,0), you activate the line tool, either click on the screen or input the (0,0) coordinates for the first point, then make a second click or input the second point coordinates at (100,0). Objects are drawn precisely to the intended size or dimension. Orthogonal (2D) views are drawn manually and intended for producing technical drawings (also known as blueprints). The traditional way of CAD drafting inherits from the old drawing board. To explain how the Sketcher works, it may be useful to compare it to the "traditional" way of drafting. A constraint solver calculates the constrained-extent of 2D geometry and allows interactive exploration of degrees-of-freedom of the sketch.Ī fully constrained sketch Basics of constraint sketching The Sketcher workbench features "constraints", allowing 2D shapes to follow precise geometrical definitions in terms of length, angles, and relationships (horizontality, verticality, perpendicularity, etc.). ![]() Moreover, together with the PartDesign Workbench operations, the Sketcher also forms the basis of the feature editing methodology of creating solids. Together with boolean operations defined in the Part Workbench, the Sketcher forms the basis of the constructive solid geometry (CSG) method of building solids. Generally, a 2D drawing is considered the starting point for most CAD models, as a 2D sketch can be "extruded" to create a 3D shape further 2D sketches can be used to create other features like pockets, ridges, or extrusions on top of the previously built 3D shapes. The FreeCAD Sketcher Workbench is used to create 2D geometries intended for use in the PartDesign Workbench, Arch Workbench, and other workbenches. ![]()
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