Working by layers

Defining the layers

A geometric representation is composed of four types of entities, namely, points, lines, surfaces, and volumes.

A layer is a grouping of entities. Defining layers in computer-aided design permits us to work collectively with all the entities in one layer.

The creation of a profile of the mechanical part in our case study will be carrried out with the help of auxiliary lines. Two layers will be defined in order to prevent these lines from appearing in the final drawing. The lines that define the profile will be assigned to one of the layers, called the "profile" layer, while the auxiliary lines will be assigned to the other layer, called the "aux" layer. When the design of the part has been completed, the entities in the "aux" layer will be eliminated.

Creating two new layers

1. Open the layer management window. This is found in Utilities Layers.

2. Create two new layers called "aux" and "profile." Enter the name of each layer in the Layers window (Figure 1) and click New.

3. Choose "aux" as the activated layer. To do this, click on "aux" to highlight it and then click on the Layer To Use button. (Next to this button will appear the name of the activated layer, "aux" in the present case.) From now on, all the entities created will belong to this layer.

Figure 1. The Layers window