ORGANISING LAYERS IN AUTOCAD

A single drawing file may be used for many reasons, the same drawing could be used for general arrangements, structure setting out, furniture layouts, reflected ceiling plans, etc. Each drawing will require a different amount of information to be shown. A well-organised file will allow that information to be shown on one drawing and not on another.

Layers

Layers are a collection of properties that can be assigned to different objects including; Name, description, Colour, Linetype and Lineweight. The visibility of layers can be controlled to show or hide information. All objects have to be drawn on a Layer.

Layers are created and managed in the Layer Manager palette. From the Ribbon Home tab > Layers panel, click the Layer Properties button.

Command-line: To start the Layer Manager from the command line, type “LA” and press [Enter].

The Layer Properties Manager palette will show.

To show or hide columns, right-click any of the headings and tick or un-tick additional properties.

You can drag the column headers around to create a layout that is custom to you.

There are many different properties associated with a Layer. There are additional properties when viewing a drawing in Paperspace.

A name is a unique name assigned to a layer.

On/Off is used to hide the contents of a layer. The objects are maintained in your computer’s memory so they are quick to turn on again. Use the On/Off feature while working to hide geometry to make drawing easier.

Freeze/Thaw is used to hide the contents of a layer and remove the objects from your computer’s memory to improve drawing performance. This means if you turn them back on again, performance can be slow as the Layers have to be re-loaded before they will display. Use Freeze/Thaw to remove information such as construction geometry that you don’t want to show on the final drawings.

Lock the content of a layer. You can still draw on a locked layer but you can’t edit what is already drawn on these layers. Use the lock to ensure the information on those layers isn’t edited such as the consultant’s information.

Controls the Colour of elements drawn on this layer. If you use CTBs these could control the colour and line weight of your printed drawings. See below the section on CTB and STB.

Linetype of elements drawn on this layer.

Lightweight of elements drawn on this layer.

Plot Style controls the way elements on the layer will print out if STBs are used. See below the section on CTBs and STBs.

For more details regarding ByLayer properties, see the Drawing on a Specific Layer section below.

The plot controls whether the layer will print or not. Use for construction geometry that you want to see on all drawings but don’t want to print out.

Description of the contents of this layer. This is especially useful if a coding standard is used such as Uniclass to aid in locating the layers.

Additional Paperspace properties include:

VP Freeze controls the appearance of a Layer in the activated viewport.

VP Color allows you to override the printed colour of elements drawn on this layer for the activated viewport. This can be especially important if using CTBs to get elements to print different values between viewports.

VP Linetype overrides the plotted Linetype of elements drawn on this layer for the activated viewport.

VP Lineweight overrides the plotted Lineweight of elements drawn on this layer for the activated viewport.

VP Transparency overrides the plotted transparency of elements drawn on this Layer for the activated viewport.

VP Plot Style overrides the style applied to the layer in the activated viewport of a sheet.

For more details regarding Viewports see Module 11-Layouts and Plotting.

Creating a New Layer

From the Layer Properties Manager, click the New Layer button. A new layer will be added to the Layer Properties Manager with the default name Layer1. Type a new name and set the properties of the layer as required.

If you don’t rename the layer, additional layers will be named with an incremental number.

Note: New layers are created from the BY LEVEL properties of the currently selected layer (Colour, Linetype, Lineweight, Plotstyle, etc)..E.g. The currently selected layer is 0. Newly created Layer1 has the same attributes as layer 0.

Drawing on a Specific Layer

Objects drawn on a specific layer, adopt the properties of the layers that you set in Layer Properties Manager, such as Color and Linetype if you use ByLayer. It is very easy to change the properties of entities simply by changing the layer values in the Ribbon Home tab > Layer panel, by clicking the Layer drop-down.

From the Ribbon Home tab> Layers panel, select your layer from the Layer drop-down.

If Layer “Example 1” is selected, and the colour is set to ByLayer in the Properties panel, objects drawn will be red.

To change an object’s layer, select the object and choose a different layer from the drop-down. The objects will then take on the new layer’s properties e.g. Selecting the layer “Example 3”, the objects will be magenta.

 

Layer Properties vs Object Property Overrides

Objects will adopt the properties of the layer they are drawn on by default. The properties can be individually overridden without changing the layer using the Properties Panel. This can be useful when you need to change the properties of an individual object but want to keep all other objects on that layer set as ByLayer values.

Select the object you wish to override. From the Ribbon Home tab > Properties panel, adjust the properties as required.

New objects that are created will adopt the current settings of the properties set in the Properties panel.

Although changing the properties of an individual element can be quite useful, it will mean if the properties of the layer are changed in the Layer Properties Manager, the update won’t show on the overridden object.

To change an element back to show the layer properties, select the element and change the property to ByLayer.

Colours are used primarily to help organise data on the screen. When printing the colours, and where necessary other properties, can be overridden by the Plot Style, controlled by a CTB or STB file.