Sketches and the workplane

A sketch is a flat drawing of lines, arcs and circles on a plane. A closed sketch can be extruded into a mass, or used as the outline of a slab, roof or shaft.

Drawing a sketch

1. Pick the Sketch tool.
2. In 3D, click a face to sketch on it (or the ground). In a plan or section, click on the drawing.
3. Click the corners. L, A, C and R switch between lines, arcs (click its end, then a point it passes through), circles (click the centre, then a point on it) and rectangles (two opposite corners, square to the sketch plane, with its width × height shown while you draw). A circle or a rectangle is a sketch of its own.
4. Click the first corner to close the sketch, or press Enter or right-click to leave it open. Esc cancels.

Shift keeps lines square.

Constraints

Select a sketch to add constraints in Properties: length, equal, horizontal, vertical, parallel, perpendicular, coincident and radius. The sketch moves to meet them, and you can drag a constraint's value to change it.

Extruding

A closed sketch is a face: it has a light wash inside its outline, in 3D, plans and sections, and Properties says Closed: a face. Extruding it makes a solid. An open one is a wire, and extrudes into a surface. A closed sketch that crosses itself has no inside: no wash, and Extrude into a mass is greyed out until no lines cross.

Select a closed sketch and press E: it becomes a mass, extruded by Extrude by in Properties. An open sketch extrudes into a surface, which a Solidify modifier can thicken.

The workplane

The workplane is the plane that sketches and guides drawn in 3D go on. Pick it in the status bar's Workplane list:

• Level (follows the plan): the working level, the usual choice;
• Pick a face…: click a face in 3D;
• Through three points…: click three points;
• Level plane you can offset: a level plane you slide up and down.

Or right-click a face and choose Set workplane here.