Sketch Design

Sketcher Overview

Click here to download Sketcher Introduction Movie
Overview: Sketcher enables you to create parametric, planar geometry on faces and planes. After you draw the geometry, you use the sketch to create pads, pockets, shafts, and surface geometry.

Sketches
Sketches are sets of 2D, fully-parametric curves. In a typical sketch, you first create base curves, and then add geometric and dimensional constraints to control the size and shape of the curves. By adding these constraints to the sketch curves, you can capture and define your design intent. This approach makes it much easier to modify the sketch shape later.

Sketch Usage
Sketches are commonly used to define section curves for pads, pockets, shafts, grooves, or surface geometry. Sketches maintain associativity to their parent and child features. If you change the geometry in a sketch, the solid model changes accordingly. Similarly, if a plane or face changes orientation or moves, any sketches attached to that plane or face move with it. You can also add dimensional and geometric constraints to the sketch. Using dimensional constraints, you can create system-defined expressions and link them to other sketch dimensions or to other features of the solid.Using Sketcher intelligently allows you to quickly modify the model to reflect changes during the product life cycle.

Sketch Placement
You create sketches on a plane or solid planar face. A sketch remains associative to its placement face. If the face changes orientation or location, the sketch changes with it.When you pick a plane or face as the sketch plane, CATIA sets the horizontal and vertical directions as the main axis of the selected plane. You can manually control the horizontal and vertical directions by selecting the horizontal and vertical reference edges, and the placement face, before creating the sketch.

Sketch Management
Organizing the data within a CAD file is always important when different people are potentially going to use the data. Data organization is especially important when using sketches because you can define sketch information in many geometrical sets, with different sketch names. Depending on the complexity of a design, even a simple, single solid model can contain over 20 sketches. With this amount of data, it is prudent to use good techniques to manage your sketches.CATIA automatically makes a sketch invisible once you use it to create a feature, such as a pad or pocket. However, it is a good practice to place each sketch into a geometric set. This makes it easier to find the information required in the Graphics window. It is also advantageous to give each sketch a descriptive name by editing the properties of the sketch.

Tips
· Always assign the In Work object to the appropriate geometrical set before creating a sketch. Although you can move objects, it may be easier to initially create objects in the correct location.