Beginning AutoCAD 2018. Cheryl R. Shrock
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First you select the layer and then you draw the objects.
Always select the layer first and then draw the objects.
It is good “drawing management” to draw related objects on the same layer.
For example, in an architectural drawing, you would select layer “walls” and then draw the floor plan.
Then you would select the layer “Electrical” and draw the electrical objects.
Then you would select the layer “Plumbing” and draw the plumbing objects.
Each layer can then be controlled independently.
If a layer is Frozen, it is not visible. When you Thaw the layer it becomes visible again. (Refer to the following pages for detailed instructions for controlling layers.)
How to select a Layer
1. Go to Ribbon = Home tab / Layers panel.
2. Select the drop-down arrow
3. Highlight the desired layer and press the left mouse button.
The selected layer becomes the “Current” layer. All objects will be located on this layer until you select a different layer.
Controlling Layers
The following controls can be accessed using the Layer drop-down arrow
On or Off
If a layer is on it is visible. If a layer is off it is not visible.
Only layers that are on can be edited or plotted.
Freeze or Thaw
Freeze and Thaw are very similar to on and off. A Frozen layer is not visible and a Thawed layer is visible. Only thawed layers can be edited or plotted.
Additionally:
a. Objects on a Frozen layer cannot be accidentally erased.
b. When working with large and complex drawings, freezing saves time because frozen layers are not regenerated when you zoom in and out.
Lock or Unlock
Locked layers are visible but cannot be edited.
They are visible so they will be plotted.
To access the following options you must use the Layer Properties Manager.
You may also access the options listed on the previous page within this dialog box.
To open the Layer Properties Manager use one of the following.
How to delete an existing layer
1. Highlight the layer name to be deleted.
2. Select the Delete Layer tool.
or
1. Highlight the layer name to be deleted.
2. Right click and select Delete Layer.
Plot or Not Plottable
This tool prevents a layer from plotting even though it is visible within the Drawing Area. A Not Plottable layer will not be displayed when using Plot Preview. If the Plot tool has a slash the layer will not plot.
Layer Color
Color is not merely to make a pretty display on the screen. Layer colors can help define objects. For example, you may assign color Green for all doors. Then, at a glance, you could identify the door and the layer by their color.
Here are some additional things to consider when selecting the colors for your layers.
Consider how the colors will appear on the paper. (Pastels do not display well on white paper.)
Consider how the colors will appear on the screen. (Yellow appears well on a black background but not on white.)
How to change the color of a layer.
A Lineweight means “how heavy or thin is the object line”.
It is “good drawing management” to establish a contrast in the lineweights of entities.
In the example below the rectangle has a heavier lineweight than the dimensions. The contrast in lineweights makes it easier to distinguish between entities.
Lineweight Settings
Lineweights are plotted with the exact width of the lineweight assigned.
But you may adjust how they are displayed on the screen. (Refer to #4 below)
Important: Before assigning lineweights you should first select the Units for Listing and Adjust Display Scale as shown below.
1. Select the Lineweight Settings box using one of the following:
Keyboard = lw <enter>
or
Status Bar = Right click on the Lineweight button.
and then left click on Lineweight Settings.