Learn autocad effectively, Exercises of Electrical and Electronics Engineering

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Learn AutoCAD

basics in 10 days

Learn to make your first AutoCAD

drawing with this guide

For a beginner in AutoCAD, this software might seem very intimidating with lots of tools, commands,

and features to learn and thousands of books, video courses and lectures to choose from for

learning the software. To ease this confusion of a beginner AutoCAD user I have prepared this

concise beginner guide which will help you in focusing your learning on only the essential tools and

commands that will make you up and running with AutoCAD in no time.

The complete learning guide is divided into 10 days with each day containing one or more of the

AutoCAD topics and commands. I recommend you go through the learning guide in the order

without skipping any day.

By the end of this 10 days guide you will be able to make your own AutoCAD drawings and modify

the existing drawings too. The last day of this guide is also dedicated to practicing a sample drawin

and we will use the tools and commands discussed in this guide to make the sample drawing.

I hope you will find this guide helpful in your journey to learning AutoCAD. For any questions reach

me on [email protected]

When AutoCAD starts for the first time it will show you the start screen as shown in the image on the left. This screen is also called the start screen and it has the template box on the left shown in red box as well as a list of recently opened drawings on the next columns. To launch the drawing area simply click on the big start box marked in the red box. The AutoCAD interface will open. On the top left of this interface, you will see AutoCAD 2018 Logo which is also a drop-down menu called application menu. This menu contains many frequently used tools like open, save and print. On the right of that application button, you will see quick access toolbar which again has some frequently used tools. Below the quick access toolbar, you will see AutoCAD ribbon with many tabs which are grouped in different categories like Home, Insert and Annotate. These tabs are further grouped into panels which contain commands of a similar category. For example, Home tab has all commands related to drawing features grouped into Draw panel, Modification of drawing related features are grouped into Modify panel and so on. Day 1: Familiarizing with the user interface

You can remove these tabs or panels and you can also bring more tabs and panel in the interface which are hidden by default. To add/remove tabs right-click in the empty area of any tab and select Show Tabs then the name of the tab from the right contextual menu. You can activate any tab by clicking on its name and then all the panels of that particular will show upon the top. Here also you can right-click in the empty area of the tab and then select Show Panels and name of the panel to activate and deactivate it as shown in the image below.

To use AutoCAD effectively you need to use a 3-button mouse with left, right button, and a middle mouse wheel with the button. Although you can use other navigation devices also and that depends completely on your preference. The standard windows mouse operations are used in AutoCAD interface also. You can left click to select any object or tool and right click to open a context-sensitive menu also called contextual menu. The contents of this menu will depend on the place where you click on the AutoCAD interface. If you press and hold middle mouse wheel and then move your mouse you will be able to pan your entire drawing in the AutoCAD drawing area. By rotating the mouse wheel, you can zoom in or zoom out different parts of the drawing. The place where you place your cursor will become center of zoom for the drawing. Understanding coordinate system is essential to understanding the way AutoCAD works. In AutoCAD, you can assign length, angles as well as coordinate values to make the required geometries. Primarily there are two types of the coordinate system which we will use to make geometries in AutoCAD and they are Cartesian and Polar. Cartesian coordinates AutoCAD follows simple Cartesian coordinate system which is a graphical method of assigning coordinates to a point in space. The simple 3D space has three coordinates namely X, Y and Z Day 2: Understanding coordinate system

which are mutually perpendicular to each other as shown in the image below. In these cases, the point of intersection of the three mutually perpendicular axes is origin represented as (0,0,0). The position of any point in 3D space can be specified using these three axes which are represented with Red, Green, and Blue axes here. But for 2D space, we only need to use X and Y axes to define the position of any point. In 2D space the simple X,Y coordinate system is used and any point in 2D space can be defined using these two coordinates only. Take the example of the image shown below. Here the origin is mentioned as 0,0 which is also the point of intersection of the X and Y Axes represented by red and green axes respectively.

In this case, point B is represented with (8<30) where 8 is the distance between point A and point B where A is the origin and 30 is the angle between line AB and the positive X-axis along the anticlockwise direction. This type of coordinate representation can also be used to specify the position of a point in 2D space and it’s generally referred as the polar coordinate system. AutoCAD starts drawing with the unit set in the default template file but you can change this unit to your preferred settings using Units window. To open the Unit window type UN on the command line and press enter. The Unit window with all the default values will show up just like the image shown below. Day 3: Setting drawing units

In this window, let’s start with the first Length panel. Change the length type to decimal if you want to use metric systems and change it to Architectural if you want to use Imperial system of feet and inches. In the next drop-down menu set the precision value of deciaml places. In the Insertion Scale set the unit to millimeter or meter if you are using deciaml and Inches if you are using the imperial system. In the angle type, you can set your prefered value like decimal degrees or degree minute second from the drop down menu. Once all of these changes are made, click on OK to accept the chanes and exit the Units window. You now have your preoper units set. You can also refer to this related article to learn more about changing units in AutoCAD. AutoCAD cursor modes AutoCAD cursor behaves in different ways when the different type of commands are active. These cursor modes help you in making the selection easily and it also helps you in identifying whether any command is active or not.

You will notice that cursor will change into a point selection cursor with two perpendicular lines and command line will show the name of command along with the prompt. Where is the command line? In case you are not able to see the command line/bar at the bottom of the drawing area, don’t panic simply press CTRL + 9 key to make it visible or to hide it. Now AutoCAD is ready for your input to make the line. Click at any point in the drawing area and the line will start from that point. Move your cursor and you will notice that the line will follow the movement of cursor and it will stretch with the cursor too. This line is also called rubber bending line which follows your cursor. Click at the second point in the drawing area and the fixed segment of the line will be made and the rubber bending line will again follow from the last point where you clicked. Repeat the process to make additional lines and when you are done making the geometry press enter or esc key to exit the command. In the example above you simply clicked at different points in the drawing area to make the line but instead of clicking at different points you can also enter the coordinate values of the point which we will see in the next example. Using absolute coordinates Let’s take the example of this triangle shown below. In this case, we have all the three coordinates of this triangle mentioned as point A, B, and C. You can make this geometry using the Line command.

1. Open the AutoCAD window and select the Line tool from the Draw panel or use its command L to start the command.
2. The command line will prompt you to specify the first point for the line. Type 0,0 for the first coordinate point which is also the point A and press enter.
3. Now we need to specify the coordinates of the second point or point B, type 10,0 and press enter again.
4. Once again, we need to specify the coordinates of the next point C, so type 14,7 and press enter.
5. Now our cursor is at point C and you can simply type 0,0 and press enter to return to the first point which is the origin. To exit the command press, enter or esc key once. As you can see that we only required the coordinates for making this triangle but the coordinates are rarely used for making real-life drawings and in most of the cases length and angle values are predominantly used. In this next example, we will learn to make the similar type of rectangle but instead of coordinates, we will use direct distance entry method. Using direct distance entry To explain this feature, I will use the triangle shown in the image below.

In this case, you can start the drawing at point A and then progressively make your drawing by entering distances. But you can also use relative coordinates as explained in the steps below.

1. Let’s start by selecting the line command and then click at a point in the drawing area, that will be the point A of the drawing. In this case point, A is not the origin and origin is somewhere else in the drawing area so we don’t know the exact coordinates of the point B. But you can use relative coordinates and assign coordinate values of point B with respect to coordinate values of point A.
2. In this case, if point A would be origin then point B should be 8,0. To make the horizontal line AB again select the line command and click at any point that will be point A and then type @8,0 for point B. Notice the @ sign before the coordinate value, this @ is added to indicate that the next coordinates are relative with respect to the point where we have previously clicked i.e. point A and it will assume point A as origin instead of absolute origin.
3. Once you have reached point B don’t exit the line command and type @0,6 and press enter. You will notice that AutoCAD will reach point C and in this case also the point B will be treated as the origin and the coordinate values of point C with respect to point B is 0, which is shown with the @ sign.
4. You can complete the triangle by clicking again at the point A and then press enter to exit the line command. Using Polar coordinates Using polar coordinates, you can add distance as well as angle values directly to the command line and they need not be entered separately. For explaining this, I will use this drawing.

In this case, we need to draw the line which is inclined at an angle of 36 degrees with respect to the positive side of X-axis and it has a length of 6 units.

1. Type L↵ and press enter to start the line command.
2. Click at any point in the drawing area to specify the first point of the line.
3. Type @6<36 on the command line and press enter, the line of required value will be made. In this case we are entering length of line after @ sign and the angle with which it is inclined is mentioned after < sign, hence @6<36 indicates a line of length 6 unit from the point of click and it is inclined at an angle of 36 degrees with respect to the positive side of X-axis. Day 5: Status bar modes There is another way of making geometries in AutoCAD by simply bypassing all the considerations of absolute or relative coordinate system and it’s called Dynamic Input. To explain the dynamic input tool, I will use image shown in the previous section where we made a line of length 6 unit inclined at an angle of 36 degrees with respect to the positive side of the X-axis. Click on the dynamic input icon of the status bar and it will turn blue when active. You can also type DYNMODE↵ then type 3 and press enter again to activate the dynamic input mode, the default value of DYNMODE system variable is -3.

Here the length field is active and it is ready for your input, type the length of the line in this field and press tab key on the keyboard. You will find that the line will be locked with a length of 6 unit and a lock sign will also appear next to the length field of the tooltip. Now enter the angle without any angle sign which in this case is 36 and press enter. And our required line is made. So, this is another quick and effective way of making geometries in the drawing. If for any reason you don’t want to use this Dynamic Input tool then click on the dynamic input icon again on the status bar to deactivate it. Using Ortho Mode So far, we have used line command to make geometries in arbitrary directions but if you want to restrict the direction of your lines in horizontal and vertical directions then you can use Ortho mode. To activate the Ortho mode click on the Orthomode icon the status bar as shown in the image below or press F8 function key on the keyboard. Select the line tool from the Draw panel or use its command L and click at a point in the drawing area. Now move your cursor around and you will see that the line will remain restricted to horizontal or vertical direction depending upon the movement of your cursor. You can click at different points to make the geometry but the lines will always remain horizontal or vertical. To deactivate the Ortho mode simply click on its icon on the status bar again or press F8 function key on the keyboard. Using Polar Tracking

Polar tracking allows you to make geometries at any angle you want. To active Polar, Tracking click on its icon on the status bar as shown in the image below. You can also activate Polar Tracking by pressing the F10 function key on the keyboard. When Polar tracking is active it will automatically deactivate the Ortho Mode. Start the Line command again by selecting its command L. Click at a point in the drawing area and move your cursor, you will notice a green tracking vector when the cursor is horizontal or vertical and this will help you in restricting the line to a horizontal and vertical direction. But this is not all, in this case, you can assign a different angle to the polar tracking mode and it will start restricting your lines to those angles. To change the angle of Polar Tracking click on the small arrow right beside the Polar tracking icon and select the angle which you want to choose. By default, 90 and its multiples will be selected but we will change it to 30 and its multiples as shown in the image below. You can select any other angle value as well if you want from the list. After making the selection move your cursor again in the drawing area and now you will find green tracking vector after an interval of every 30 degrees or at every angle which is a multiple of 30 degrees.