AutoCAD’s Menu Systems

AutoCAD has two menu systems that allows you to communicate with it. The two menu systems are Toolbar menu and Ribbon menu. See Figure 1-1. You can, and should, add the Pull-down menu to either the Toolbar or the Ribbon menu. You can use either menu system when completing labs exercises in this book. You can switch between them, if you wish.

Toolbar Menus

Ribbon Menus Figure 1-1 AutoCAD Menu Systems

WORK ALONG: Setting AutoCAD’s Interface Using Toolbar Menus

If you are using Ribbon menus, skip to WORK ALONG: Setting AutoCAD’s Interface Using Ribbon Menus

Step 1

Launch AutoCAD. AutoCAD’s blank window will display. (Figure Step 1)

Figure Step 1

Step 2

Click the New icon. This will open the Select Template dialogue box. (Figure Step 2)

Figure Step 2

Step 3

In the Select template dialogue box, click the template file: 3D Layout English to highlight it. Then click the Open button. This will open AutoCAD’s Graphic window. (Figure Step 3)

Figure Step 3

Step 4

Click the small arrow in the Workplace Switching icon on the Status bar. Click the workspace: AutoCADbook to set it as the current workspace. Make sure that the check mark is beside the workspace: AutoCADbook as shown in the figure. (Figure Step 4A and 4B)

Figure Step 4A

Figure Step 4B

Step 5

Check to ensure that the tab Model is enabled. It is located on the bottom left corner of the Graphic window. If it is not enabled, click it with the left mouse button. (Figure Step 5)

Figure Step 5

Step 6

Disable all features on the Status bar by clicking any that display with a blue background as shown in Figure Step 6A. All features should display with a gray background as shown in Figure Step 6B. (Figure Step 6A and 6B)

Figure Step 6A

Figure Step 6B

USER TIP: You can easily check to see if a feature on the Status bar is enabled or disabled by holding your graphic cursor on the icon. A pop up window will display indicating the name of the feature and whether it is currently on or off as shown in the figures below.

Step 7

Move the Graphic cursor onto any toolbar icon and right click the mouse. This will pull down a list of all available toolbar menus. The ones that are preceded with a checkmark are enabled and are currently displayed in the Graphic window. Ensure that the toolbars: Layers, Orbit, Properties, Standard, Styles, UCS, UCS II, View, and Visual Styles are the only ones enabled. Click on the name to toggle the display of the toolbar. (Figure Step 7)

Figure Step 7

Step 8

Your Graphic screen should match the figure very closely. (Figure Step 8)

Figure Step 8

Step 9

Enter the MENUBAR command. If is set to 0, set it to 1, as shown below.

Command: MENUBAR

Enter new value for MENUBAR <0>: 1

Command:

Step 10

Click File on the Pull-down menu. Click Exit to close AutoCAD. If you are asked if you want to save the drawing, click No. (Figure Step 10)

Figure Step 10

Step 11

Skip to Viewing in 3D

WORK ALONG: Setting AutoCAD’s Interface Using Ribbon Menus

If you are using Toolbar menus, go to Viewing in 3D

Step 1

Launch AutoCAD. AutoCAD’s blank window will display. (Figure Step 1)

Figure Step 1

Step 2

Click the New icon. This will open the Select Template dialogue box. (Figure Step 2)

Figure Step 2

Step 3

In the Select Template dialogue box, click the template file: 3D Layout English to highlight it. Then click the Open button. This will open AutoCAD’s Graphic window. (Figure Step 3)

Figure Step 3

Step 4

Click the small arrow in the Workplace Switching icon on the Status bar. Click the workspace: 3D Modeling to set it as the current workspace. Ensure that the check mark is beside the workspace: 3D Modeling as shown in the figure. (Figure Step 4A and 4B)

Figure Step 4A

Figure Step 4B

Step 5

Enter the MENUBAR command and if is set to 0, set it to 1, as shown below. Command: MENUBAR

Enter new value for MENUBAR <0>: 1

Command:

Step 6

Check to ensure that the tab Model is enabled. If it is not enabled, click it with the left mouse button. (Figure Step 6)

Figure Step 6

Step 7

Disable all features on the Status bar by clicking any that display with a blue background as shown in Figure Step 7A. All features should display with a gray background as shown in Figure Step 7B. (Figure Step 7A and 7B)

Figure Step 7A

Figure Step 7B

Step 8

Click File on the Pull-down menu. Click Exit to close AutoCAD. If you are asked if you want to save the drawing, click No. (Figure Step 8)

Figure Step 8

USER TIP: You can easily check to see if a feature on the Status bar is enabled or disabled by holding yourgraphic cursor on the icon. A pop up window will display indicating the name of the feature and whether it is currently on or off as shown in the figures on the right.

Viewing in 3D

While working in 2D (two dimensions), the model was always viewed looking down from the top. The only viewing adjustment made, when looking at the model, was the distance (zoom) and the location (pan). There was no need to change the viewing angle. Working in 3D (three dimensions) is quite different. While the model can still be zoomed and panned, you can change the viewing direction and angle of the model.

Throughout the AutoCAD 2D book, the objects being drawn and modified were called the drawing objects even though they were actually model objects on the top view of a model. The reason this was done was to keep it simple and allow you to concentrate on learning to draw and modify geometry. In the AutoCAD 3D book, all objects that are drawn in model space will be referred to as model objects and all objects drawn in paper space will be called drawing objects.

UCS Icon

The User Coordinate System (UCS) icon displays the location and orientation of the current coordinate system. Its location, which is controlled by you, is at either the current coordinate system origin point or in the lower-left corner of the current viewport. When constructing a model, it is best to locate it at the origin point as taught in Modules 3 and 4. Figure 1-2 shows the two different icons as they would appear in a 3D viewing orientation.

The 2D Wireframe UCS Icon

The 3D Wireframe UCS Icon Figure 1-2 Coordinate System Icons

A Wireframe Model

A model is the 3 dimensional object drawn at full size and located accurately in relation to model space origin or X0Y0Z0 in the World UCS. A wireframe model is a real-world 3D object represented by lines, circles, arcs, and/or plines located along the edge of the model. See Figure 1-3. A wireframe model is hollow in the centre. That is the reason that lines and arcs on the opposite side of the model can be seen. Think of it as the skeleton of an object. The same model when surfaced or constructed as a solid model will appear as shown in Figure 1-4.

Surfacing a wireframe model and constructing a solid model are covered in Modules 12 to 30.

Wireframe models can be used to view the model from any vantage point, generate standard views in a drawing, generate exploded and perspective views, plus can be used as a skeleton when constructing the surfaced model. A wireframe model cannot be shaded or rendered. A wireframe model can also be used to analyze spatial relationships, including the shortest distance between corners and edges and checking for interferences.

It is important to plan, organize, and construct your model using layers and colors. This will allow you to more easily visualize a complex model and differentiate between objects in various views.

Figure 1-3
Wireframe Model

Figure 1-4
A Surfaced or Solid Model

A View

A view is an area displayed by the viewing angle and direction and the location of the target. The current view is the view of the model that is being displayed in the Graphic window. There are many ways of setting the current view of the model and all of them will be covered throughout the AutoCAD 3D book. In this module, using the VIEW command is taught to either select a preset view or set and name user defined views. The basic principles of the orbit commands are also covered.

AutoCAD Command: VIEW

The VIEW command is used to display the preset views or to define, name, and display user defined views of the model.

Shortcut: none

View Toolbar

View Pull-down

Home Ribbon

 

AutoCAD Commands: 3DORBIT, 3DFORBIT, 3DCORBIT

The 3DORBIT, 3DFORBIT, and 3DCORBIT commands allows the user to dynamically orbit the

model changing the viewing angle, viewing direction, and target of the view.

Shortcut: none

View Pull-down

Orbit Toolbar

AutoCAD Commands: UCSICON

The UCSICON command is used to configure and control the display of the UCS icon.

Shortcut: none

View Pull-down

WORK ALONG: Using the UCSICON, VIEW, and 3DFORBIT Commands

Step 1

Using the NEW command, start a new drawing using the template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 01-1.

Step 3

In the View pull-down, select Display – UCS Icon – Properties. Ensure that both On and Origin enabled as shown in the figure. This will open the UCS Icon dialogue box. Ensure that the settings are the same in your dialogue box as they are in the figure. (Figure Step 3A and 3B)

Figure Step 3A

Figure Step 3B

Step 4

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Using the INSERT command, insert the block: AutoCAD 3D Lab 01-1 at the coordinates 0,0,0. Explode the block that you just inserted. Your model should appear as shown in the figure. (Figure Step 4)

Figure Step 4

Step 5

If you are using Toolbar menus, use the View toolbar or if you are using Ribbon menus, use the View section of the Home tab to complete Steps 7 and 8. (Figure Step 5A and 5B)

Figure Step 5A

Figure Step 5B

Step 6

Enter the system variable UCSORTHO, as shown below, and set it to 0.

Command: UCSORTHO

Enter new value for UCSORTHO <1>: 0

Command:

Step 7

Click the Top view icon. Note how the model is now being viewed from the top as shown in the figure. Continue to change the view to display the ten predefined views. Note how the view of the model changes each time you click an icon. (Figure Step 7A, 7B, 7C, 7D, 7E, 7F, 7G, 7H, 7I, and 7J)

Figure Step 7A

Figure Step 7B

Figure Step 7C

Figure Step 7D

Figure Step 7E

Figure Step 7F

Figure Step 7G

Figure Step 7H

Figure Step 7I

Figure Step 7J

Step 8

Change the current view to SE Isometric as shown in the figure. (Figure Step 8)

Figure Step 8

AUTHOR’S COMMENTS: The 3DFORBIT command activates and displays the arcball. The arcball allows you to dynamically orbit the model changing the viewing angle, viewing direction and target. The arcball displays a small circle at each quadrant. See Figure 1-5

Depending on the location of the cursor when the left mouse button is held down, the model will orbit around a different axis. If the cursor is located:

1. outside the arcball the Z
2. on the upper or lower circles the X
3. on the left or right circles, the Y axis
4. inside the arcball, the XYZ

In this module, only the basic principles of the 3DFORBIT command are covered. Play with this command and practice orbiting the model around each of the axis. After entering the command, move the cursor to the desired location press and hold down the left mouse button and move the cursor. Press Esc to exit the command. Any change can be reversed with the U command.

Be careful when orbiting the model. It is very easy to over-orbit it and lose your mental view of the model. Orbit it slowly and deliberately keeping a mental view of the model throughout. If you lose the mental view of the model, you can always exit the orbit and change the view to SE Isometric and then start the orbit again. The 3DFORBIT command will be covered in greater detail as you work your way through the AutoCAD 3D book.

Figure 1-5
The Arcball

Step 9

Enter the 3DFORBIT command using either the toolbar or the pull-down menu. It will display the arcball around the model. Zoom and pan the model to locate it in the centre of the arcball. (Figure Step 9A, 9B, and 9C)

Figure Step 9A

Figure Step 9B

Figure Step 9C

Step 10

Move the cursor onto the small circle on the left side. Press and hold down the left mouse button and while holding it down, move the cursor slowly to the right. until your model appears similar to the figure. You do not have to move it very far. (Figure Step 10)

Figure Step 10

Step 11

Move the cursor onto the small circle on the bottom. Press and hold down the left mouse button and while holding it down, move the slowly up until your model appears as shown in the figure. (Figure Step 11)

Figure Step 11

Step 12

Move the cursor inside the arcball. Press and hold down the left mouse button and while holding it down, move it until the model appears as shown in the figure. (Figure Step 12)

Figure Step 12

Step 13

Press Esc to exit the command. Change the current view to SE Isometric. (Figure Step 13)

Figure Step 13

Step 14

Using 3DFORBIT, orbit the model to appear similar to the figure. It does not have to match exactly. (Figure Step 14)

Figure Step 14

Step 15

Enter the VIEW command using either the toolbar or ribbon. This will open the View Manager dialogue box. (Figure Step 15A and 15B)

Figure Step 15A

Figure Step 15B

Step 16

In the Views box, click Model Views to highlight it as shown in the figure and then click the New icon. This will open the New View dialogue box. In the View name box, enter the name: Module 1 View. Click OK to see the view name as shown in the figure. Click OK to close the dialogue box. (Figure Step 16A, 16B, and 16C)

Figure Step 16A

USER TIP: When constructing 3D wireframe models, it is best to view the model in a position that best allows geometry to be inserted and edited. When first beginning to construct 3D models, it is best to start with the SE Isometric view (the Home view) and then slightly orbit it with one of the orbit commands. Do not over-orbit it and lose your mental view of the model. At times, wireframe models can be hard to visualize since they can be visualized inside out. This is a skill that can be learned but in the beginning it is best to keep a mental view of the model.

Figure Step 16B

Figure Step 16C

Step 17

Change the current view to SE Isometric. (Figure Step 17)

Figure Step 17

Step 18

Save and close the drawing.

Key Principles

Checking the Accuracy of Models

It is extremely important in AutoCAD to draw with 100% accuracy. This cannot be stressed enough as it is essential that each model be positioned and sized perfectly. Models constructed in the lab exercises, in the AutoCAD 3D book, can be checked for accuracy by overlaying it with a key. As a beginner, this helps you know that the models are drawn accurately and shows you any part of the model that is drawn incorrectly. As you become more experienced, you will not require keys to check your models.

WORK ALONG: Checking the Accuracy of Models

Step 1

Using the NEW command, start a new drawing using the template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Lab 02-1.

Step 3

Check to ensure that the Model tab is enabled. If it is not, enable it by clicking it with the left mouse button. (Figure Step 3)

Figure Step 3

Step 4

Ensure that all features on the Status bar are disable by clicking any that are enabled. Your Status bar should match the figure. (Figure Step 4)

Figure Step 4

Step 5

Ensure that ByLayer is enabled in the first 3 boxes on the Properties menu. (Figure Step 5)

Properties Toolbar

Home Ribbon

Step 6

Click Format on the Pull-down menu and click Units to open the Drawing Units dialogue box. (Figure Step 6A and 6B)

Figure Step 6A
Format Pull-down

Figure Step 6B

Step 7

Pull down the Insertion scale list and select Inches. Click OK to close the Drawing Units dialogue box. (Figure Step 7)

Figure Step 7

Step 8

Click the Insert pull-down and select Block. This will open the Insert dialogue box. (Figure Step 8)

Figure Step 8

Step 9

Click the small triangle at the end of the Name box. It will pull-down the list of the block names contained in the drawing file. (Figure Step 9)

Figure Step 9

Step 10

Click the block: AutoCAD 3D Lab 02-1. It will highlight as shown in the figure. The name you select is always the name of the drawing for the lab exercise you are working on. (Figure Step 10)

Figure Step 10

Step 11

Ensure that the three Specify On-screen boxes are disabled. (Figure Step 11A and 11B)

Figure Step 11A

Figure Step 11B

Step 12

Click the OK button.

Step 13

This will insert a magenta colored overlay key on your model. If there double objects or places where the users model and the magenta model don’t match, the users model is incorrect. If only one model displays, even though it may share the colors magenta and red, the model is accurate. The magenta key resides on layer: Key. If the model is incorrect, turn layer: Key off and correct the model before going on to the next lab exercise or module. After your model is corrected, check it again by turning layer: Key on. (Figure Step 13)

Figure Step 13

Step 14

Save and close the drawing.

Key Principles

The World Coordinate System

AutoCAD has two distinct three-dimensional coordinate systems: the World Coordinate System (WCS) and the User Coordinate System (UCS). The World Coordinate System is permanently located at the absolute coordinates X0Y0Z0. It is a fixed coordinate system which can never be moved. The WCS is normally not used to construct models. You will be using it in this module to construct models as learning tool only.

The User Coordinate System (UCS) is the coordinate system that is used to construct 3D models. The UCS can be placed exactly at the WCS or at any location in 3D space. In this module, model will be constructed with the UCS located at the WCS. It is essential to be able to locate and orientate the UCS to construct most models. This is taught in Module 4 and 5.

The UCS Icon

Figure 3-1 shows the UCS icon and the positive X, Y and Z directions indicated by the UCS icon. When constructing models, it is very important to know which direction is positive and negative on all three axis.

Figure 3-1
UCS Icon Coordinate Directions

When the UCS is located at the World Coordinate System, it will display a small square at the origin as can be seen in Figure 3-2. If it is located at any other location, it will display as shown in Figure 3-3.

Figure 3-2 UCS at the World
Coordinate System

Figure 3-3 UCS Not at the World Coordinate System

The Right-Hand Rule

Even though the 3D UCS icon indicates the positive Z direction, it is important to know how it is obtained. AutoCAD uses the right-hand rule to find the positive Z direction. See Figure 3-4. To use the right-hand rule, you must first know the positive X and Y directions of the current UCS.

Using your right hand, point your thumb in the direction of the positive X axis. Extend your index finger in the direction of the positive Y axis. The middle finger indicates the direction of the positive Z axis. By rotating your hand, the X, Y and Z axes will rotate to change the UCS location and orientation. It is important to be able to visualize how and where to move the UCS as you construct more complicated models.

Figure 3-4
The Right-hand Rule

While drawing in 2D, you only had to worry about entering the X and Y coordinates. Since the Z coordinate was omitted, AutoCAD used the default value of zero. When drawing in 3D, you must add the Z value in some coordinate input. For example, to enter the coordinates X2Y3Z4, enter 2,3,4 if it is an absolute coordinate and @2,3,4 if it is a relative coordinate.

Absolute X0Y0Z0

The absolute coordinate 0,0,0 is the origin of the World Coordinate System. This is the same location used in 2D when only 0,0 was entered. This is an important coordinate location as everything drawn in model space relates back to this location. Keep this in mind when drawing all future models. It is especially important when constructing models that relate to real world locations. For example, when drawing a map, X0Y0Z0 is located at the equator and your model must be drawn in relation to that location.

WORK ALONG: Drawing 3D Wireframe Models with the UCS Located at the WCS

Step 1

Using the NEW command, start a new drawing using the template: 3D Layout English.

Step 2

Save the drawing with the name: AutoCAD 3D Workalong 03-1. (Figure Step 2)

Figure Step 2
Dimensioned Solid Model

Step 3

Set the current view to SE Isometric. (Figure Step 3)

Figure Step 3

Step 4

Ensure that the UCS Icon is enabled (On) and the Origin is enabled as shown in Module 1 WORKALONG: Using the UCSICON, VIEW, and 3DFORBIT Commands.

Step 5

Set layer: Model as the current layer. Enter the LINE command, as shown below, to draw the lines to start the construction of the model. (Figure Step 5)

Command: LINE

Specify first point: 0,0,0

Specify next point or [Undo]: @2,0

(Since you are working at Z zero, you can omit the Z value.)

Specify next point or [Undo]: @2,2

Specify next point or [Close/Undo]: @4,0

Specify next point or [Close/Undo]: @0,2

Specify next point or [Close/Undo]: @-8,0

Specify next point or [Close/Undo]: C

Command:

(Draw the object that is located on the XY axis as you did in 2D.)

Figure Step 5

Step 6

Using the OFFSET command, offset the two lines 1.5 units as shown in the figure. Change the layer properties of the two lines to layer: Construction. (Figure Step 6)

Figure Step 6

Step 7

Use the CIRCLE command to draw a 2 diameter circle with its centre located at the intersection of the two construction lines. (Figure Step 7)

Figure Step 7

Step 8

Freeze layer: Construction. Enter the COPY command, as shown below, and copy the three lines and the circle 4 units in the positive Z direction. (Figure Step 8).

Command: COPY

Select objects:

(Select the three lines and the circle as shown in Figure Step 8.)

Select objects:

Specify base point or displacement, or [Multiple]: 0,0,0

Specify second point of displacement or <use first point as displacement>: @0,0,4

(Copy the 4 objects 4 units in the positive Z direction. Looking at the UCS or using the right- hand rule will indicated if it is a positive or negative direction.)

Command:

Figure Step 8

Step 9

Using the 3DFORBIT command, orbit the model slightly. (Figure Step 9)

Figure Step 9

Step 10

Using the COPY command, copy the 2 lines 2 units in the positive Z directions. (Figure Step 10)

Figure Step 10

Step 11

Use the LINE command to draw six lines between the ends of the existing lines. Ensure that you snap to the ends of the lines. (Figure Step 11)

Figure Step 11

Step 12

Using the COPY command, copy the short line located at the right end of the model two times. Ensure that you use snap mode to locate the lines exactly. (Figure Step 12)

Figure Step 12

Step 13

Draw three lines between the ends of the existing lines. Ensure to snap to the ends of the existing lines. (Figure Step 13)

Figure Step 13

Step 14

Using the VIEW command, save the current view with the name: Working Isometric. (Figure Step 14)

Figure Step 14

Step 15

Change the current view to SE Isometric. (Figure Step 15)

Figure Step 15

Step 16

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Insert the key: AutoCAD 3D Workalong 03-1. It will overlay the model with a magenta model. (Figure Step 16)

Figure Step 16

Step 17

Save and close the drawing.

WORK ALONG: Drawing 3D Wireframe Models With the UCS Located at the WCS

 Step 1

Using the NEW command, start a new drawing using the template: 3D Layout Metric.

Step 2

Save the drawing with the name: AutoCAD 3D Workalong 03-2. (Figure Step 2)

Figure Step 2
Dimensioned Solid Model

Step 3

Set the current view to SE Isometric. (Figure Step 3)

Figure Step 3

Step 4

Ensure that the UCS Icon is enabled (On) and the Origin is enabled as shown in Module 1, WORKALONG: Using the UCSICON, VIEW, and 3DFORBIT Commands.

Step 5

Set layer: Model as the current layer. Draw the shape of the top of the object. Use the ARRAY command to speed up the construction. (Figure Step 5)

Figure Step 5

Step 6

Using the COPY command, as shown below, copy all of the objects 10 units in the negative Z direction. (Figure Step 6)

Command: COPY

Select objects:

(Select all objects.)

Select objects:

Specify base point or displacement, or [Multiple]: 0,0,0

Specify second point of displacement or <use first point as displacement>: @0,0,-10

Command:

Figure Step 6

Step 7

Using the 3DFORBIT command, orbit the model slightly until it appears similar to the figure. (Figure Step 7)

Figure Step 7

Step 8

Draw the vertical lines by snapping to the endpoints to complete the wireframe model. (Figure Step 8)

Figure Step 8

Step 9

Using the VIEW command, save the current view with the name: Working Isometric. (Figure Step 9)

Figure Step 9

Step 10

Change the view to SE Isometric. (Figure Step 10)

Figure Step 10

Step 11

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Millimeters. Insert the key:

AutoCAD 3D Workalong 03-2. It will overlay the model with a magenta model. (Figure Step 11)

Figure Step 11

Step 12

Save and close the drawing.

Key Principles

Lab Exercise 3-1

Time allowed: 45 minutes.

Step 1

Save and name the drawing: AutoCAD 3D Lab 03-1.

Step 2

Draw all construction objects on layer: Construction and model objects on layer: Model.

Step 3

Draw a wireframe model of the object shown in the figure. (Figure Step 3A and 3B)

Figure Step 3A
Dimensioned Solid Model

Figure Step 3B Completed Wireframe Model SE Isometric View

Step 4

Start your model with the current view SE Isometric. If required, orbit it slightly with 3DFORBIT to help the line of sight.

Step 5

Save the isometric working view with the name: Working Isometric.

Step 6

When complete, freeze layer: Construction.

Step 7

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches.

Step 8

Check your drawing with the key. The key name is the same as the drawing name.

Hint 1

Figure Hint 1
Construction Steps

Lab Exercise 3-2

Time allowed: 45 minutes.

Step 1

Save the drawing with the name: AutoCAD 3D Lab 03-2.

Step 2

Draw all construction objects on layer: Construction and all model objects on layer: Model.

Step 3

Draw a wireframe model of the object shown in the figure. (Figure Step 3A, 3B, 3C, and 3D)

Figure Step 3A
Dimensioned Solid Model

Figure Step 3B Completed Wireframe Model SE Isometric View

Figure Step 3C Key Detail

Figure Step 3D View of Keyway – Orbited

Step 4

Start your model with the current view SE Isometric. If required, orbit it slightly with 3DFORBIT to help the line of sight.

Step 5

Save the isometric working view with the name: Working Isometric.

Step 6

When complete, freeze layer: Construction.

Step 7

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Millimeters.

Step 8

Check your drawing with the key. The key name is the same as the drawing name.

Hint 1

Figure Hint 1 Construction Steps

IMPORTANT – PLEASE READ BEFORE COMPLETING THIS MODULE

 AutoCAD 2015 has a bug using the LINE command in 3D. The LINE command works properly when either the World or Top is the current UCS. When any other UCS is the current UCS, the cursor of the LINE command will display the new line in the wrong location. It locates the line in the correct location after you execute the LINE command. It displays correctly when snapping to existing objects and only appears wrong when using coordinates or drawing lines freehand.

A good workaround is to use the PLINE command rather than the LINE command, as it works correctly. After you complete the PLINE command, you can explode the pline to create a line object.

This bug is only in AutoCAD 2015. The LINE command in AutoCAD 2016, 2017 and 2018 works in all UCS locations.

The User Coordinate System

The User Coordinate System (UCS) is the coordinate system used to construct 3D models. It can be located at the WCS or at any location or orientation in 3D space. Being able to locate and orientate the UCS anywhere in 3D space is the secret of 3D modeling.

The User Construction Plane

If you draw an imaginary line from the X axis to the Y axis on the user coordinate system, it forms a imaginary triangular plane as shown in Figure 4-1. When you locate the UCS onto the 3D model, as shown in Figure 4-2, you can see this imaginary triangular plane laying on the surface. Next, picture the plane expanded to fill the whole surface it is located on. See Figure 4-3. This surface is called the User Construction Plane (UCP).

Figure 4-1
User Construction Plane

The easiest method of drawing 3D models is to locate and orientate the user construction plane to lie on the surface you currently want to insert or modify object(s) on. Relocate the location of the UCS and continue your model construction until you complete the model. You can use the Z axis to copy the object(s) and draw at a depth parallel to the UCP.

Figure 4-2
User Construction Plane on the WCS

Figure 4-3
UCS Plane expanded to cover the Whole Surface

By relocating and orientating the UCS to different locations, you can draw or modify objects on any surface you want. Figure 4-4 shows the user construction plane located on the right side of the model and Figure 4-5 shows it located on the inclined surface.

Figure 4-4
UCP located on the Right Side

In this module, all model construction will be drawn in the with the UCS located at the World or in one of the preset orthographic locations only. In Module 5, locating the UCS anywhere in model space will be taught.

Figure 4-5
UCP located on an Inclined Surface

AutoCAD Command: UCSMAN

The UCSMAN command is used to locate, orientate, and manage the UCS.

Shortcut: none

Tools Pull-down

UCS II Toolbar

Home Ribbon

WORK ALONG: Moving the UCS to the Preset Locations

Step 1

Using the NEW command, start a new drawing using the template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 04-1. Save it in the folder: CAD Courses/AutoCAD 3D/Lab Exercises

Step 3

Set the current UCS to World. Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Using the INSERT command, insert the block: AutoCAD 3D Lab 01-1 at the coordinates 0,0,0. Explode the block.

Step 4

Set the current view to SE Isometric. Your wireframe model should appear as shown in the figure. (Figure Step 4)

Figure Step 4

Step 5

Enter the UCSMAN command. It will open the UCS dialogue box. Enable the Settings tab and ensure that the settings in the dialogue box matches the figure. (Figure Step 5)

Figure Step 5

Step 6

Enable the Orthographic UCS’s tab. Select Front and then click the Set Current button. (Figure Step 6)

Figure Step 6

Step 7

The wireframe model should now appear as shown in the figure. Notice how the XY axis lies on the front plane of the model. (Figure Step 7)

Figure Step 7

Step 8

Using either the UCS II toolbar or the Home tab ribbon. (Figure Step 8A and 8B)

Figure Step 8A

Figure Step 8B

Step 9

Set the current UCS location to Right and the UCS icon will move onto the right side of the model. Note that the XY plane is now located on the right side plane of the wireframe model. (Figure Step 9A and 9B)

Figure Step 9A

Figure Step 9B

Step 10

Click the UCS command icon as shown in the figures. With osnap enabled, snap to the end of the line. Note that the UCS icon has now moved to the end of the line that you just selected but it remains located on the right side plane. (Figure Step 10A, 10B, 10C, and 10D)

Figure Step 10A

Figure Step 10B

Figure Step 10C

Figure Step 10D

Step 11

Click Top from the pull-down list. The UCS icon will move onto the top plane of the model. In this case, it locates itself on the WCS. (Figure Step 11)

Figure Step 11

Step 12

Using the UCS command, move the UCS to corner as shown in the figure. Ensure that you snap to the end of the line. Note how the name of the UCS will display ‘ Unnamed ‘. (Figure Step 12)

Figure Step 12

Step 13

Click World from the pull-down list. The UCS icon will move onto the WCS. (Figure Step 13)

Figure Step 13

Step 14

Save and close the drawing.

WORK ALONG: Drawing 3D Wireframe Models Using the UCS

Step 1

Using the NEW command, start a new drawing using the template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 04-2. (Figure Step 2A and 2B)

Figure Step 2A
Dimension Wireframe Model

Figure Step 2B
Solid Model SE Isometric View

Step 3

Ensure that the current UCS is set to World and the current view is set to SE Isometric.

Step 4

Set layer: Model as the current layer.

Step 5

Using the LINE command, draw the lines to outline the Top view. (Figure Step 5)

Figure Step 5

Step 6

Copy all of the lines 3 units in the positive Z direction. (Figure Step 6)

Figure Step 6

Step 7

Using the 3DFORBIT command, orbit the model slightly. (Figure Step 7)

Figure Step 7

Step 8

Using the LINE command, draw the 6 vertical lines. Ensure that you enable object snap and snap to endpoints of the existing lines. (Figure Step 8)

Figure Step 8

Step 9

Set the current UCS to Right and then locate the icon by snapping to the corner of the model as shown in the figure. (Figure Step 9)

Figure Step 9

Step 10

Draw the necessary construction lines using the OFFSET command. Change their layer to layer: Construction. Draw the arc and the circle. (Figure Step 10)

Figure Step 10

Step 11

Copy the arc and the circle in the negative Z direction. (Figure Step 11)

Figure Step 11

Step 12

Trim or delete necessary lines. (Figure Step 12)

Figure Step 12

Step 13

Set the current UCS to Front and then locate it to the corner as shown in the figure. (Figure Step 13)

Figure Step 13

Step 14

Draw the necessary construction lines using the OFFSET command. Change their layer to layer: Construction. Draw the object lines as shown in the figure. (Figure Step 14)

Figure Step 14

Step 15

Copy the lines in the negative Z direction and add the necessary object lines. (Figure Step 15)

Figure Step 15

Step 16

Trim or delete the necessary lines and freeze layer: Construction to complete the wireframe model. (Figure Step 16)

Figure Step 16

Step 17

Change the current view to SE Isometric. (Figure Step 17)

Figure Step 17

Step 18

Set the current UCS to World. (Figure Step 18)

Figure Step 18

Step 19

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches.

Insert the key: AutoCAD 3D Workalong 04-2. It will overlay the model with a magenta wireframe model. (Figure Step 19)

Figure Step 19

Key Principles

Lab Exercise 4-1

Time allowed: 40 minutes.

Step 1

Save and name the drawing: AutoCAD 3D Lab 04-1 as shown above.

Step 2

Draw all construction objects on layer: Construction and all model objects on layer: Model.

Step 3

Start your model with the current view in SE Isometric. If required, orbit it slightly with 3DFORBIT to help your line of sight.

Step 4

Draw a wireframe model of the object. (Figure Step 4A and 4B)

Figure Step 4A
Dimensioned Solid Model

Figure 4B Completed Wireframe Model SE Isometric View

Step 5

When complete, freeze layer: Construction.

Step 6

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches.

Step 7

Change the current UCS to World and check the model with the key.

Hint 1

Figure Hint 1
Construction Steps

Lab Exercise 4-2

Time allowed: 40 minutes.

Step 1

Save and name the drawing: AutoCAD 3D Lab 04-2, as shown above.

Step 2

Draw all construction objects on layer: Construction and all model objects on layer: Model.

Step 3

Start your model with the current view in SE Isometric. If required, orbit it slightly with 3DFORBIT to help your line of sight.

Step 4

Draw a wireframe model of the object. (Figure Step 4A, 4B, and 4C)

Figure Step 4A
Dimensioned Solid Model

Figure Step 4B Completed Wireframe Model SE Isometric View

Figure Step 4C
Key Detail

Step 5

When complete, freeze layer: Construction.

Step 6

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Millimeters.

Step 7

Change the current UCS to World and check the model with the key.

Hint 1

Figure Hint 1

Lab Exercise 4-3

Time allowed: 40 minutes.

Step 1

Save and name the drawing: AutoCAD 3D Lab 04-3, as shown above.

Step 2

Draw all construction objects on layer: Construction and all model objects on layer: Model.

Step 3

Start your model with the current view in SE Isometric. If required, orbit it slightly with 3DFORBIT to help your line of sight.

Step 4

Draw a wireframe model of the object. (Figure Step 4A, 4B, and 4C)

Figure Step 4A Dimensioned Solid Module SE Isometric View

Figure Step 4B
Completed Wireframe Model SE Isometric View

Figure Step 4C Solid Model Rotated View

Step 5

When complete, freeze layer: Construction.

Step 6

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches.

Step 7

Change the current UCS to World and check the model with the key.

Hint 1

Figure Hint 1

Locating the UCS in 3D Space

In Module 4, the UCSMAN command and the UCS II toolbar or ribbon were used to locate the UCS at preset orthographic locations on the model. In this module, the UCS command and the UCS toolbar or ribbon will be used to move and orientate the UCS to locations that are required to construct more complicated models. The most useful option is locating the UCS by selecting 3 points on the model. While it is still necessary to use the predefined orthographic UCS locations for model construction, not all models can be built using only them.

AutoCAD Command: UCS

The UCS command is used to locate and orientate the UCS on the model or in model space.

Shortcut: none

UCS II Toolbar

Tool Pull-down

Home Ribbon

WORK ALONG: Locating and Orientating the UCS Using the UCS Toolbar

Step 1

Using the NEW command, start a new drawing using the template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 05-1.

Step 3

Set the UCS to World. Enter the UNITS command and in the Units dialogue box, set the Insertion Units to Inches. Using the INSERT command, insert the block: AutoCAD 3D Lab 01-1 at the coordinates 0,0,0.

Step 4

Explode the block you inserted in step 3.

Step 5

Set the current view to SE Isometric. Your model should appear as shown in the figure. (Figure Step 5).

Figure Step 5

Step 6

Set the UCS location to Right. (Figure Step 6)

Figure Step 6

Step 7

Click the Origin icon and then snap to the end of the line shown in Figure Step 7A. Your model should now appear as shown in the figure. (Figure Step 7A and 7B)

Figure Step 7A

Figure Step 7B

Step 8

Enable object snap. Click the 3 Point icon. When prompted, select the end of the inclined line. This is the X0Y0Z0 of the UCS. (Figure Step 8)

Figure Step 8

Step 9

For the second point, select end of the inclined line on the right side of the model. This is the positive X axis. (Figure Step 9)

Figure Step 9

Step 10

For the third point, select the end of the inclined line on the top. This is the positive Y axis. Your model should now appear as shown in the figure. (Figure Step 10A and 10B)

Figure Step 10A

Figure Step 10B

Step 11

Using what you learned in Steps 8 to 10, locate the UCS as shown in the figure. Ensure that the UCS plane lies on the inclined plane. (Figure Step 11)

Figure Step 11

Step 12

Using what you learned in Step 8 to 10, locate the UCS as shown in the figure. Ensure that the UCS plane lies on the plane. (Figure Step 12.)

Figure Step 12

Step 13

Click the World UCS icon. The UCS icon will now be located as shown in the figure. (Figure Step 13)

Figure Step 13

Step 14

Click the UCS Previous icon and the UCS should now return back to last location. (Figure Step 14)

Step 1

Step 15

Save and close the drawing.

WORK ALONG: Drawing a 3D Wireframe Model by Locating the UCS

Step 1

Using the NEW command, start a new drawing using the template: 3D Layout Metric.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 05-2. (Figure Step 2A, 2B, and 2C)

Figure Step 2A
Dimensioned Wireframe Model SE Isometric View

Solid Model – View from Top.

Figure Step 2C
Solid Model – View from Bottom.

Step 3

If you are using toolbar menus, you will be using the UCS, UCS II, and View toolbars. If you are using ribbon menus, enable the Home tab.

Step 4

Ensure that the UCS is located at World. (Figure Step 4)

Figure Step 4

Step 5

Change the UCS location to Front. (Figure Step 5)

Figure Step 5

Step 6

Change the current view to Front. The UCS icon should now appear as shown in the figure. (Figure Step 6)

Figure Step 6

Step 7

Set layer: Model as the current layer. Draw the front contour of the model as shown in the figure. Drawing it in 2D is sometimes easier. It could have been drawn in the 3D view also. (Figure Step 7)

Figure Step 7

Step 8

Change the current view to SE Isometric. Your model should now appear as shown in the figure. (Figure Step 8)

Figure Step 8

Step 9

Copy the lines 100 millimeters in the negative Z direction.

Step 10

Orbit the model slight as shown in the figure. Add the lines as shown in the figure. (Figure Step 10)

Figure Step 10

Step 11

Using the 3 Point method, locate the UCS to the top of the inclined plane. (Figure Step 11)

Figure Step 11

Step 12

Using OFFSET command, offset the existing lines to locate the centre of the circle and arc on the inclined plane. Change the lines to layer: Construction. Insert the circle and the arc and copy them 25 millimeters to the bottom plane. Before you do complete this step, read the User Tip at the end of this workalong. (Figure Step 12)

Figure Step 12

Step 13

Trim or delete the lines as required. Using the 3 Point method, locate the UCS to the upper incline plane. (Figure Step 13)

Figure Step 13

Step 14

Using the OFFSET command, offset the existing lines to locate the centre of the slots on the upper inclined plane. Change the offset lines to layer: Construction. Draw the slots and copy them 25 units to the bottom of the inclined plane. (Figure Step 14)

Figure Step 14

Step 15

Using the 3 Point method, locate the UCS to the top plane. (Figure Step 15)

Figure Step 15

Step 16

Construct the square hole, copy it and trim the lines. (Step 16A and 16B)

Figure Step 16A

Figure Step 16B

Step 17

Freeze layer: Construction. Change the current UCS to World and the current view to SE Isometric. (Figure Step 17)

Figure Step 17

Step 18

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Millimeters. Insert the key: AutoCAD 3D Workalong 05-2. It will overlay the model with a magenta model. If it overlays your model perfectly, your model is accurately drawn. (Figure Step 18)

Figure Step 18

Step 19

Save and close the drawing.

USER TIP: If you have to copy existing geometry in the Z direction, an easy way to do it is to use the COPY command and select the objects first (P1 and P2 – Step 1).

To indicate the copy distance and direction, snap to the ends of an existing line (P3 and P4 in Step 2).

Step 1

Step 2

Key Principles

Lab Exercise 5-1

Time allowed: 60 minutes.

Step 1

Save and name the drawing: AutoCAD 3D Lab 05-1.

Step 2

Draw a wireframe model of the object shown in the figure. (Figure Step 2A ,2B, 2C, 2D, 2E, 2F, and 2G)

Figure Step 2A
Dimensioned Wireframe Model SE Isometric View

Figure Step 2B Completed Wireframe Model SE Isometric View

Figure Step 2C Front View – Base View

Figure Step 2D Detail of Inclined plane

Figure Step 2E Detail of Keyway

Figure Step 2F Solid Model – SE Isometric View

Figure Step 2G Solid Model – Rotated View

Step 3

Draw all construction objects on layer: Construction and all model objects on layer: Model.

Step 4

Start your model with the current view SE Isometric. If required, orbit it slightly with 3DFORBIT to help your line of sight.

Step 5

When complete, freeze layer: Construction.

Step 6

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Millimeters.

Step 7

Change the current UCS to World and check the model with the key.

Hint 1

See the steps below to draw the Front view.

Step 1 – Draw the bottom lines first.

Step 2 – Offset the lines.

Step 3 – Trim the lines and change length of the top Line to 100 units.

Step 4 – Daw a line perpendicular at the end and extend the bottom inclined line.

Lab Exercise 5-2

Time allowed: 40 minutes.

Step 1

Save and name the drawing: AutoCAD 3D Lab 05-2.

Step 2

Draw a wireframe model of the object shown in the figure. (Figure Step 2A, 2B, 2C, 2D, and 2E)

Figure Step 2A
Dimensioned Wireframe Model SE Isometric View

Step 3

Draw all construction objects on layer: Construction and all model objects on layer: Model.

Step 4

Start your model with the current view SE Isometric. If required, orbit it slightly with 3DFORBIT to help your line of sight.

Step 5

When complete, freeze layer: Construction.

Step 6

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Millimeters.

Step 7

Change the current UCS to World and check the model with the key.

Figure Step 2B
Completed Wireframe Model SE Isometric View

Figure Step 2C
Completed Wireframe Model Orbited View

Figure Step 2C
Completed Wireframe Model Orbited View

Figure Step 2E
Solid Model – SE Isometric View

Lab Exercise 5-3

Time allowed: 60 minutes.

Step 1

Save and name the drawing: AutoCAD 3D Lab 05-3.

Step 2

Draw a wireframe model of the object shown in the figure. (Figure Step 2A, 2B, 2C, 2D, 2E, 2F, and 2G)

Figure Step 2A
Dimensioned Wireframe Model SE Isometric View

Step 3

Draw all construction objects on layer: Construction and all model objects on layer: Model.

Step 4

Start your model with the current view SE Isometric. If required, orbit it slightly with 3DFORBIT to help the line of sight.

Step 5

When complete, freeze layer: Construction.

Step 6

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches.

Step 7

Change the current UCS to World and check the model with the key.

Figure Step 2B Completed Wireframe Model

Figure Step 2C
Front View

Figure Step 2D
Solid Model – SE Isometric View

Figure Step 2E
Detail of Top

Figure Step 2F
Detail of Bottom

Figure Step 2G
Detail of Square Hole in Inclined

Hint 1

To draw the inclined line, see the steps below. (Figure Hint 1)

Step 1

Draw a construction line from corner to corner and a 1 diameter construction circle with the centre at the midpoint of the line.

Step 2

Draw two lines from the endpoints tangent to the circle.

Step 3

Extend the lines and trim the horizontal lines.

Figure Hint 1
Step 1                                                 Step 2                                                 Step 3

Lab Exercise 5-4

Time allowed: 60 minutes.

Figure Step 2A
Dimensioned Wireframe Model SE Isometric View

Step 1

Save and name the drawing: AutoCAD 3D Lab 05-4.

Step 2

Draw a wireframe model of the object. (Figure Step 2A, 2B, 2C, 2D, 2E, and 2F)

Step 3

Draw all construction objects on layer: Construction and all model objects on layer: Model.

Step 4

Start your model with the current view SE Isometric. If required, orbit it slightly with 3DFORBIT to help your line of sight.

Step 5

When complete, freeze layer: Construction.

Step 6

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches.

Step 7

Change the current UCS to World and check the model with the key.

Figure Step 2B
Right Side View

Figure Step 2C
Front and Back Detail TYP.

Figure Step 2D
Bottom Detail TYP.

Figure Step 2E
Solid Model – SE Isometric View

Figure Step 2F Completed Wireframe Model
SE Isometric View

Hint 1

To draw the arc, you must draw the construction circle and lines to locate its centre. (Figure Hint 1)

Figure Hint 1

The AutoCAD 3D book was written with competency based modules. What that means is that you have not completed each module until you have mastered it. The Competency Test module contains multiple choice questions and a comprehensive lab exercise to test your mastery of the set of modules that you completed. There are no answers or keys supplied in a Competency Test module since it is meant to be checked by your instructor. If there are any parts of this module that you have trouble completing, you should go back and reread the module or modules containing the information that you are having trouble with. If necessary, redo as many lab exercises required until you fully understand the material.

If you are completing this book:

• Without the aid of an instructor, complete the written test and the lab exercise.
• In a classroom with an instructor, the instructor will give instructions on what to do after this module has been completed.

Multiple Choice Questions

Select the BEST answer.

1. Which one of the following coordinate locations would specify a point 2 units in the positive Y direction from the last point entered relative to the current UCS?
   1. @*2,0,0
   2. @&0,2,0
   3. @0,2,0
   4. @#0,2,0
   5. @0,0,2
2. What are the two distinct 3-dimensional coordinate systems used by AutoCAD?
   1. The WCC and UCS.
   2. The WCS and UCC.
   3. The WSC and USC.
   4. The WCS and UCS.
   5. The UCS and USC.
3. What two commands can be used to restore a saved UCS location?
   1. UCS and VIEW
   2. UCSMAN and UCS
   3. 3DORBIT and UCSMAN
   4. VIEW and USC
   5. UCSICON and UCSMAN
4. Which one of the following statements is a false statement when describing the User Coordinate System?
   1. It’s current location can be named, saved and restored in the future.
   2. It can be located anywhere in 3D space.
   3. It defines the User Construction Plane.
   4. It is always located at the absolute coordinates X0Y0Z0.
   5. It is used to construct 3D models
5. In Figure 6-1, what does the small square indicate? Choose the BEST answer.
   
   

   Figure 6-1
   1. The location of the last point entered.
   2. The UCS is at the centre of the model.
   3. The endpoint of the Z axis.
   4. The location where X, Y and Z axis meet.
   5. The UCS is located at the WCS.
6. Which one of the following coordinate locations would specify a point 3 units in the Z direction from the last point entered relative to the absolute X0Y0Z0 or the WCS?
   1. @*0,0,3
   2. @-0,0,3
   3. @3,0,0
   4. @#0,0,3
   5. @*3,0,0
7. Which one of the following is a false statement when describing a wireframe model?
   1. It is a real-world 3D object represented by lines, circles, arcs and/or plines.
   2. It is actually a 2 dimensional object.
   3. It does not have any surfacing and is not solid.
   4. You can see lines and curves right through it that would not appear in a solid object.
   5. If it was a real object, you could put your finger through it.
8. Which one of the following statements is a false statement when describing the World Coordinate System? Choose the BEST answer.
   1. It is always located on the top view of the model.
   2. It can be located anywhere in 3D space.
   3. It is fixed and cannot be moved.
   4. It is always located at the absolute coordinates X0Y0Z0.
   5. It is not used to construct 3D models.
9. What command is used to define a new UCS location using the 3 Point UCS method?
   1. UCS
   2. UCSMAN
   3. 3DORBIT
   4. VIEW
   5. UCSICON
10. What direction does the thumb indicate in the right-hand rule?
    1. Positive Y
    2. Positive Z
    3. Negative Y
    4. Negative Z
    5. Positive X

Lab Exercise 6-1 OPEN BOOK

Step 1

Save and name the drawing: AutoCAD 3D Lab 06-1.

Step 2

Draw a wireframe model of the object. (Figure Step 2A, 2B, 2C, 2D, 2E, and 2F)

Step 3

Draw all construction objects on layer: Construction and all model objects on layer: Model.

Figure Step 2A
Completed Wireframe Model – SE Isometric View

Figure Step 2B
The Model – NE Isometric View Slightly Orbited

Figure Step 2C
The Model – NW Isometric Slightly Orbited

Figure Step 2D
Right Side View

Figure Step 2E
Detail of Inclined View

Figure Step 2F
Detail of Rear View

Step 4

When complete, freeze layer Construction.

Step 5

Change the view to SE Isometric. (Figure Step 5)

Figure Step 5
SE Isometric View

Visualizing 3D Models

In the first six modules, all of the wireframe models that you constructed were referenced to a given 3D view of the model. Since most technical drawings used in the drafting and design world are 2D multiview drawings, 3D models must be able to be drawn using a multiview drawing as a reference to find the model’s shape and dimensions. To construct a 3D model, you must be able to mentally visualize the 3D model using a multiview drawing as a reference.

A good way for you to learn to visualize a 3D model from a 2D multiview drawing is to first draw the model as an isometric drawing. By doing this, it is easier to form a mental image from the multiview drawing. After practicing this for while, you will be able to visualize and construct 3D models without drawing the isometric first.

Figure 7-1
An Isometric Drawing

An isometric drawing is a 2-dimensional drawing that has the XYZ axis drawn at 120 degrees apart as shown in Figure 7-1. In this module, drawing the isometric on an isometric grid will be taught. An isometric grid has the grid lines drawn at 120 degrees as shown in Figure 7-2. Figure 7-3 shows a rectangular box drawn on the isometric grid.

Figure 7-2 An Isometric Grid

Figure 7-3
A Rectangular Box Drawn on an Isometric Grid

WORK ALONG: Visualizing 3D Models

Step 1

Using the NEW command, start a new drawing using the template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 07-1.

Step 3

Set the UCS to World and the view to Top. Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Using the INSERT command, insert the block: AutoCAD 3D Workalong 07-1 at the coordinates 0,0,0. Explode the block. The drawing should appear as shown in the figure. (Figure Step 3)

Figure Step 3

Step 4

Change the layer of the isometric grid from layer: 0 to layer: Grid.

Step 5

Lock layer: Grid and set the lineweight of layer: Object to 0.35 mm. (Figure Step 5)

Figure Step 5

Step 6

Enable OSNAP and LWT. (Figure Step 6)

Figure Step 6

Step 7

Figure Step 7A shows the multiview drawing of Object 7-1. Set layer: Object as the current layer and draw a box 6 grids long, 5 grids wide and 4 grids high. Where it is drawn is not that important but it should be located somewhere in the top left corner. Ensure that all lines are snapped to the grid intersections. Since layer: Grid is locked, the lines can be freely moved on layer: Object, as required. (Figure Step 7A, 7B, and 7C)

Figure Step 7A
Multiview Drawing – Object 7-1

Figure Step 7B

Figure Step 7C

Step 8

To draw the contour of the Front view, count the number of grids for the diagonal cut off. It is 3 grids on the X axis and 2 grids on the Z axis. Using those dimensions, draw the inclined lines on the front and rear view and add the lines to connect them. (Figure Step 8)

Figure Step 8

Step 9

Trim and delete the lines to complete the contour of the front view. (Figure Step 9)

Figure Step 9

Step 10

Add the lines to cut out the contour of the Right Side view. (Figure Step 10)

Figure Step 10

Step 11

Trim and delete the necessary lines to complete the Right Side view contour and then add the lines to form the Top view contour. (Figure Step 11)

Figure Step 11

Step 12

Trim and delete any unwanted lines to complete the isometric object: Object 7-1. The drawing should appear similar to figure. (Figure Step 12A and 12B)

Figure Step 12A

Figure Step 12B

Step 13

Using what was just taught, draw the isometric drawing of: Object 7-2. Draw it in the top right corner of the grid. (Figure Step 13)

Figure Step 13

Step 14

The figures show the necessary steps. Try to complete the isometric without looking at the figure. (Figure Step 14A, 14B, 14C, and 14D)

Figure Step 14A

Figure Step 14B

Figure Step 14C

Figure Step 14D

Step 15

Your drawing should now appear similar to the figure. (Figure Step 15)

Figure Step 15

Step 16

Using what was just taught, draw isometric drawings of the four objects: Object 7-3 to Object 7-6. For the answers, see Figure “Isometric drawing of Object 7-1 to Object 7-6” at the end of this chapter. Try to visualize the 3D model by looking at the multiview drawing and then draw the isometric. Do not look at the answers until you have done your best to complete the isometric drawing of each object. (Figure Step 16)

Figure Step 16

Step 17

Save and close the drawing.

Key Principles

Lab Exercise 7-1

Time allowed: 40 minutes.

Step 1

Draw all construction objects on layer: Construction and all model objects on layer Model. When complete, freeze layer: Construction.

Step 2

Draw a wireframe model of the object. (Figure Step 2A, 2B, and 2C)

Figure Step 2A
Dimensioned Multiview Drawing

Step 3

Start with the current view SE Isometric. If required, orbit it slightly with 3DFORBIT to help your line of sight.

Step 4

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Change the current UCS to World and check the model with the key.

Figure Step 2B
Complete Wireframe Model

Figure Step 2C
Solid Model – SE Isometric View

Isometric drawing of Object 7-1 to Object 7-6

Rotating in 3D

AutoCAD has individual 2D and 3D rotate commands. The 2D rotate command is ROTATE and in 3D, it is ROTATE3D. In this module, using the ROTATE3D command will be taught. It is used to rotate the model in 3D space. The main difference between the two commands is that the ROTATE command uses a XY point to rotate around and the ROTATE3D command uses two XYZ points or an axis to rotated around. The ROTATE command can be used while 3D modeling as long as all of the objects being rotated are 2D objects and located on the current UCS. If 3D objects are going to be rotated in 3D space, the ROTATE3D command must be used. See Figure 8-1.

Figure 8-1
Rotating 3D Model in 3D Space

WORK ALONG: Rotating Wireframe Models in 3D Space

Step 1

Using the NEW command, start a new drawing using the template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 08-1.

Step 3

On layer: Model, draw a wireframe model of the object shown in the multiview drawing. (Figure Step 3A and 3B)

Figure Step 3A
Dimensioned Multiview Drawing

Figure Step 3B
SE Isometric View

Step 4

Enter the commands, as shown below, to set the TRIM and EXTEND commands while working in 3D.

Command: TRIM

Current settings: Projection=None, Edge=No Extend

(Note how in this case, the Projection is set to None and Edge to No Extend. Your computer might be different.)

Select cutting edges … (Select an object, any object)

Select objects or <select all>: (Press Enter)

Select object to trim or shift-select to extend or [Fence/Crossing/Project/Edge/eRase/Undo]: P

Enter a projection option [None/Ucs/View] <None>: U

(Enter U for Ucs.)

[Fence/Crossing/Project/Edge/eRase/Undo]: E

Enter an implied edge extension mode [Extend/No extend] <No Extend>: E

(Enter E for Edge and then another for Extend. That means that the intersection of the two objects that you are trimming or extending do not have to physically intersect. AutoCAD will extend them to find the apparent intersection for you.)

Command: EXTEND

Current settings: Projection=Ucs, Edge=Extend

Select cutting edges …

Select objects or <select all>:

(By entering the EXTEND command, you will now see the settings are set for this command as well.)

Command:

Step 5

Enter the TRIM command as shown below. The Current settings: should be set as shown. If not, go back and redo Step 4. If they match, abort the command.

Command: TRIM

Current settings: Projection=UCS, Edge=Extend

Select boundary edges …

Step 6

Enter the ROTATE3D, as shown below, to rotate the model 90 degrees counterclockwise around the X axis. (Figure Step 6)

Command: ROTATE3D

Current positive angle: ANGDIR=counterclockwise ANGBASE=0

Select objects:

Specify opposite corner: 22 found

(Using a window, select all the objects)

Select objects:

Specify first point on axis or define axis by [Object/Last/View/Xaxis/Yaxis/Zaxis/2points]: X

(Rotate around the X axis.)

Specify a point on the X axis <0,0,0>:

(Press Enter to select 0,0,0 as the base point of the rotation.)

Specify rotation angle or [Reference]: 90

(The angle is positive since looking along the X axis towards 0,0,0, counterclockwise is the direction you want to rotate.)

Command:

Figure Step 6

Step 7

Using what you learned in Step 6, rotate the model 90 degrees around the Y axis. This rotation will have be negative 90 degrees since the rotation is clockwise. (Figure Step 7)

Figure Step 7

Step 8

Change the UCS to the front and locate it at the centre of the circle. (Figure Step 8)

Figure Step 8

Step 9

On layer: Construction, draw a line from 0,0,0 at any angle and any length. The line you draw does not have to match the figure exactly. Draw it by eye. (Figure step 9)

Figure Step 9

Step 10

Change to the Front view to ensure that the line was drawn correctly. (Figure Step 10)

Figure Step 10

Step 11

Change the current view to SE Isometric and enter the ROTATE3D command, as shown below, to rotate the model using the Reference option. (Figure Step 11)

Command: ROTATE3D

Current positive angle: ANGDIR=counterclockwise ANGBASE=0

Select objects:

(Select all of the model objects in a window. Do not include the reference line that you just drew in the selection.)

Specify opposite corner: 22 found

Select objects:

Specify first point on axis or define axis by

[Object/Last/View/Xaxis/Yaxis/Zaxis/2points]: Z

(Rotating around the Z axis.)

Specify a point on the Z axis <0,0,0>:

Specify rotation angle or [Reference]: R

Specify the reference angle <0>: (cen) P1

Specify second point: (cen) P2

Specify the new angle: (cen) P1

(Note that you have to select the P1 location twice.)

Specify second point: (end) P3

Command:

Figure Step 11

Step 12

The wireframe model should now appear as shown in Figure Step 12A. Change the current view to Front to ensure that the model was rotated correctly. (Figure Step 12A and 12B)

Figure Step 12A

Figure Step 12B

Step 13

Save and close the drawing.

Key Principles

Lab Exercise 8-1

Time allowed: 60 minutes.

Step 1

Draw all construction objects on layer: Construction and all model objects on layer: Model.

Step 2

Draw a wireframe model of the object shown in the figure. (Figure Step 2A, 2B, 2C,and 2D)

Step 3

When complete, freeze layer: Construction.

Figure Step 2A
Dimensioned Multiview Drawing

Figure Step 2B
Completed Wireframe Model SE Isometric View

Figure Step 2C
Solid Model – SE Isometric View

Figure Step 2D
Solid Model – NE Isometric View

Step 4

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Change the location of the UCS to World and check the model with the key.

Step 5

Ensure that the USC is set to World and the current view is SE Isometric. (Figure Step 5)

Figure Step 5

Step 6

Rotate the model 90 degrees around the X axis. (Figure Step 6)

Figure Step 6

Step 7

Rotate the model 90 degrees around the Y axis. (Figure Step 7)

Figure Step 7

Step 8

Rotate the model 90 degrees around the X axis. (Figure Step 8)

Figure Step 8

Step 9

Rotate the model 90 degrees around the Z axis. (Figure Step 9)

Figure Step 9

Step 10

Save and close the drawing.

Lab Exercise 8-2

Time allowed: 40 minutes.

Step 1

Draw all construction objects on layer: Construction and all model objects on layer: Model.

Step 2

Draw a wireframe model of the object shown in the figure. (Figure Step 2A, 2B, 2C, and 2D)

Step 3

When complete, freeze layer: Construction.

Figure Step 2A
Dimensioned Multiview Drawing

Figure Step 2B
Completed Wireframe Model SE Isometric View

Figure Step 2C
Solid Model SE Isometric View

Figure Step 2D
Solid Model NW Isometric View

Step 4

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Change the location of the UCS to World and check the model with the key.

Step 5

Save and close the drawing.

Modifying 3D Objects

When constructing 3D models, the only time the 2D commands ARRAY and MIRROR can be used is if all the objects that are selected in the command lie on the 2D plane of the current UCS. To array or mirror objects in 3D space, the corresponding 3D commands must be used.

3D Array

A 3D array, using the 3DARRAY command, is very similar to a 2D array, using the ARRAY command, that was taught in the AutoCAD 2D book. A rectangular and a polar 3D array can be preformed.

Rectangular Array

A 2D rectangular array uses rows and columns. In 3D, the third dimension of the array is called a level. Rows are along the Y axis, columns are along the X axis and levels are along the Z axis. Distance between the rows, columns and levels can be positive or negative. See Figure 9-1.

Figure 9-1
3D Rectangular Array

Polar Array

A 2D polar array only requires a XY point to array around while a 3D polar array, two XYZ points, a line or an axis must be specified to array around. See Figure 9-2.

Figure 9-2
3D Polar array

3D Mirroring

A 3D mirror, using the MIRROR3D command, is very similar to a 2D mirror, using the MIRROR command, that was taught in the AutoCAD 2D book. A 2D mirror requires two XY points or a line to mirror around while a 3D mirror requires three XYZ points or a plane to mirror around. See Figure 9-3.

Figure 9-3
3D Mirror

WORK ALONG: Creating a 3D Rectangular Array

Step 1

Using the NEW command, start a new drawing using the template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 09-1.

Step 3

Set layer: Model as the current layer.

Step 4

Using the figures as a reference, draw the wireframe model. Note the location of the WCS. (Figure Step 4A and 4B)

Figure Step 4A
Right Side View

Figure Step 4B
Wireframe Model

Step 5

Using the figures as a reference, draw the circle and then copy it to create a hole through the Front view. (Figure Step 5A, 5B, and 5C)

Figure Step 5A
Hole Detail

Figure Step 5B
Wireframe Model

Figure Step 5C
Solid Model

Step 6

Study the figure. It shows the hole pattern that will be used in the 3D ARRAY command. (Figure step 6)

Figure Step 6

Step 7

Ensure that Osnap is disabled.

Step 8

Ensure that the current UCS is set to the Front and enter the 3DARRAY command, as shown below, to array the holes. Your finished drawing should appear as shown. (Figure Step 8A and 8B)

Figure Step 8A

Figure Step 8B
Solid Model – Rotated View

Command: 3DARRAY

Select objects:

Specify opposite corner: 2 found

(Select the two circles.)

Select objects:

Enter the type of array [Rectangular/Polar] <R>:

(Rectangular array)

Enter the number of rows (—) <1>: 2

Enter the number of columns (|||) <1>: 11

Enter the number of levels (…) <1>: 2

Specify the distance between rows (—): -0.75

(In the negative Y direction.)

Specify the distance between columns (|||): 1

(In the positive X direction.)

Specify the distance between levels (…): -7.5

(In the negative Z direction.)

Command:

WORK ALONG: Creating a 3D Polar Array

Step 1

Using the NEW command, start a new drawing using the template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 09-2.

Step 3

Draw all model objects on layer: Model and all construction objects on layer: Construction. (Figure Step 3A, 3B, and 3C)

Figure Step 3A
Multiview Drawing – Gear is 0.5 Inches Thick

Figure Step 3B
Detail of Gear Teeth

Figure Step 3C
Solid Model – SE Isometric View

Step 4

Set the current UCS to Front and change the current view to Front. Draw three circles and a construction line from the centre to the quad as shown in the figure. Take all of the sizes from the multiview drawing. (Figure Step 4)

Figure Step 4

Step 5

Using the ARRAY command, array the construction line 192 times around. Use the centre of the circle as the basepoint for the array. (Figure Step 5)

Figure Step 5

Step 6

On layer: Model, draw two gear teeth by drawing lines from the intersection of the lines and the circles. (Figure Step 6)

Figure Step 6

Step 7

Turn layer: Construction off and your drawing should appear as shown in the figure. (Figure Step 7)

Figure Step 7

Step 8

Trim the two outer circles to form the repeat pattern of one gear tooth. (Figure Step 8)

Figure Step 8

Step 9

Change the current view to SE Isometric. (Figure Step 9)

Figure Step 9

Step 10

Copy all objects 0.5 inches in the -Z direction. 0.5 is the thickness of the gear. (Figure Step 10)

Figure Step 10

Step 11

Add lines to complete the gear tooth. (Figure Step 11)

Figure Step 11

Step 12

Enter the 3DARRAY command, as shown below, to complete the wireframe model of the gear. (Figure Step 12A and 12B)

Command: 3DARRAY

Select objects:

Specify opposite corner: 12 found

(Select the lines that make one gear tooth in a window.)

Select objects:

Enter the type of array [Rectangular/Polar] <R>:P

(Polar array.)

Enter the number of items in the array: 32

Specify the angle to fill (+=ccw, -=cw) <360>:

(Accept the default.)

Rotate arrayed objects? [Yes/No] <Y>:

(Accept the default.)

Specify centre point of array: (cen) P1

Specify second point on axis of rotation: (cen) P2

(From centre to centre of the circles defines the endpoints of a line to be used as the axis of the array.)

Command:

Figure Step 12A

Figure Step 12B

Step 13

Save and close the drawing.

WORK ALONG: Creating a 3D Mirror

Step 1

Figure Step 1

Open the drawing: AutoCAD 3D Workalong 09-1. The drawing should appear as shown in the figure. (Figure Step 1)

Step 2

Using the SAVEAS command, save the drawing with the name: AutoCAD 3D Workalong 09-3.

Step 3

Enter the MIRROR3D command, as shown below, to mirror the model. (Figure Step 3)

Command: MIRROR3D

Select objects:

Specify opposite corner: 124 found

(Select all object in the model in a window.)

Select objects:

Specify first point of mirror plane or [Object/Last/Zaxis/View/XY/YZ/ZX/3points] <3points>: (end) P1

Specify second point on mirror plane: (end) P2

Specify third point on mirror plane: (end) P3

Delete source objects? [Yes/No] <N>:

(Accept the default.)

Command:

Figure Step 3

Figure 9-4
Mirror Plane

Step 4

The completed mirrored model is shown in the figure. (Figure Step 4A and 4B)

Figure Step 4A

Figure Step 4B
Solid Model – SE Isometric View

Step 5

Save and close the drawing.

Drafting Lesson: Break Lines

To simplify or speed up drawing orthographic views of a model, sometimes views are only partially drawn. In these cases, the cut off portion of the view is not required for the reader to visualize or construct the model. See the figures for examples of short and long break lines.

Long Break
(Drawn by Eye)

Short Break
(Drawn by Eye)

Example Of Break Lines

Key Principles

Lab Exercise 9-1

Time allowed: 50 minutes.

Step 1

Draw all construction objects on layer: Construction.

Step 2

Draw all model objects on layer: Model.

Step 3

Draw a wireframe model of the object shown in the figure. (Figure Step 3A and 3B)

Figure Step 3A
SE Isometric View

Figure Step 3B
Dimensioned Multiview Drawing

Step 4

Using the figure as a reference, anywhere in model space, draw a wireframe model of one nut and one bolt. (Figure Step 4A and 4B)

Figure Step 4A
Dimensioned Multiview Drawings of Nut and Bolt

Figure Step 4B
Wireframe Models of Nut and Bolt

Step 5

Move one bolt and one nut to the bottom outside bolt location as shown in the figure. The bolt comes up from the bottom and nut is on top of the plane. (Figure Step 5A, 5B, 5C, and 5D)

Figure Step 5A
Bolt Pattern – Bottom View

Figure Step 5B

Figure Step 5C

Figure Step 5D

Step 6

Array the nut and bolt to match the figure. (Figure Step 6)

Figure Step 6

Step 7

Mirror the completed model. (Figure Step 7)

Figure Step 7

Step 8

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Millimeters.

Step 9

Change the current UCS to World and check the model with the key.

Step 10

Save and close the drawing.

Lab Exercise 9-2

Time allowed: 50 minutes.

Step 1

Draw a wireframe model of the centre octagon and one arm as shown in the figures. Details of the arm are in Figure Step 1D Detail B and Figure Step 1E Detail A. (Figure Step 1A, 1B, 1C, 1D, and 1E)

Figure Step 1A

Figure Step 1B

Figure Step 1C

Figure Step 1D Detail B – Dimensioned Multiview Drawing of Arm

Figure Step 1E Detail A – Dimensioned Multiview Drawing of Arm

Step 2

Array the arm as shown in the figure. (Figure Step 2)

Figure Step 2

Step 3

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches.

Step 4

Change the current UCS to World and check the model with the key.

Step 5

Save and close the drawing.

Lab Exercise 9-3

Time allowed: 50 minutes.

Step 1

On layer: Model, draw a wireframe model as shown in the figure. See the multiview drawing in Figure 1 Step B. (Figure Step 1A and 1B)

Figure Step 1A

Figure Step 1B
Dimensioned Multiview Drawing

Step 2

Mirror the wireframe drawn in Step 1. Erase the extra lines and clean up the model to create one model. (Figure Step 2)

Figure Step 1A

Step 3

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. Change the current UCS to World and check the model with the key.

Step 4

Turn layer: Key off.

Step 5

Note the location of the UCS and rotate the model. (Figure Step 5)

Figure Step 5

Step 6

Note the location of the UCS and rotate the model. (Figure Step 6)

Figure Step 6

Step 7

Save and close the drawing.

Visual Styles

In the first nine modules, drawing wireframe models was taught. A wireframe model is a real-world 3D object represented by lines, circles, arcs, and/or plines located along the edges of the model. For that reason, you can see right through the model and see objects that would not be visible if the model was surfaced or solid. Think of it as the skeleton of a model.

In Modules 12 to 30, constructing surface and solid models is taught. AutoCAD software comes complete with five predefined visual styles. In this module, viewing surface and solid models using these five styles is covered.

The VSCURRENT command is used to set the current visual style that the model will be displayed. See Figure 10-1. You can change the current visual style as required.

Figure 10-1
Realistic Visual Style of a Solid Model

AutoCAD Command: VSCURRENT

The VSCURRENT command is used to set the current visual style (shade mode) to be applied to a surface or solid model.

Shortcut: VS

Visual Style Toolbar

View Pull-down

Home Ribbon

WORK ALONG: Setting the Current Visual Style of a Model

Step 1

Using the NEW command, start a new drawing using the template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 10-1.

Step 3

Enter the UNITS command. In the Units dialogue box, set the Insertion Units to Inches. With the current UCS set in World, use the INSERT command to insert the block:

AutoCAD 3D Workalong 10-1 at the coordinates 0,0,0. Explode the block. Be careful to only explode it once.

Step 4

Set the current view to SE Isometric. Your model should now appear as shown in the figure. (Figure Step 4)

Figure Step 4

Step 5

Change the layer of both solid models to layer: Model.

Step 6

You should now have two solid models. To check this, open the Properties window and select one of the solid models. When selected, the object type in the top box of the Properties windows should indicate that the object is a 3D Solid. If the object type is anything else, exit and delete the drawing. Start this workalong again from Step 1. Be careful when using the EXPLODE command to explode the block only once. (Figure Step 6)

Figure Step 6

Step 7

If you are using Toolbars menus, enable the Visual Styles toolbar. If you are using the Ribbon Menus, click the Home tab. Enable the 2D Wireframe visual style icon. You can tell when the current visual style is 2D Wireframe by the appearance of the UCS icon. (Figure Step 7)

Figure Step 7

Step 8

Click the 3D Wireframe visual style icon. You can tell when the current visual style is 3D Wireframe by the appearance of the UCS icon. (Figure Step 8)

Figure Step 8

Step 9

Click the 3D Hidden visual style icon. Note how when the current visual style is 3D Hidden, the model appears solid and only displays the visible objects. (Figure Step 9)

Figure Step 9

Step 10

Change the layer of both solid models to layer: Solid 1.

Step 11

Click the Realistic visual style icon and note how when the current visual style is Realistic, the appearance of the model is the most basic realistic view of a shaded solid or surfaced model. (Figure Step 11)

Figure Step 11

Step 12

Click the Conceptual visual style icon and note how when the current visual style is Conceptual, the appearance of the solid model is more of an artistic look. (Figure Step 12)

Figure Step 12

Step 13

Delete the cylindrical solid model leaving only one solid model. Change the current visual style to Realistic and your model should now appear as shown in the figure. (Figure Step 13)

Figure Step 13

Step 14

If you are using Toolbar menus, enable the display of the Orbit toolbar. If you are using Ribbon menus, use the View-Orbit pull-down menu. Click the Constrained Orbit icon. (Figure Step 14A and 14B).

View Pull-down
Figure Step 14A

Orbit Toolbar
Figure Step 14B

Step 15

When constrained orbit command is active, it displays the icon as shown in the figure. (Figure Step 15)

Figure Step 15

Step 16

Orbit the model and note how this command affects the position of the model. Press Esc to exit the command.

Step 17

Click the Free Orbit icon and orbit the model. Note how this command affects the position of the model. Press Esc to exit.

Step 18

Click the Continuous Orbit icon and use it to orbit the model. Read the Author’s Comments. (Figure Step 18)

Figure Step 18

AUTHOR’S COMMENTS: The continuous 3D orbit feature is an interesting and fun feature in AutoCAD. After you enter this command, the Continuous 3D Orbit icon, Figure 10-2, will appear on the Graphic window. Hold down the mouse’s pick button, spin the model and release the button. The model will start to rotate continuously until you stop it by clicking in the Graphic window or by pressing the Esc key. The faster you spin it, the faster the model rotates.

Figure 10-2
Continuous 3D Icon

Step 19

Set the current view to SE Isometric.

Step 20

Save and close the drawing.

WORK ALONG: Using the Viewport Controls Menu

Step 1

Open the drawing: AutoCAD 3D Workalong 10-1. (Figure Step 1)

Figure Step 1

Step 2

Enter the system variable VPCONTROL and set it to ON, as shown below.

Command: VPCONTROL

Enter new value for VPCONTROL <OFF>: ON

Command:

Step 3

Step 2 will enable the display of the Viewport Controls menu located in the top left corner of the Graphic window. (Figure Step 3A, 3B, and 3C)

Figure Step 3A
Toolbar Menu

Figure Step 3B
Ribbon Menu

Figure Step 3C

Step 4

Click the small dash on the left side of the menu. This will pull down a list of menu items. Ensure that all items are disabled, as shown in the figure. (Figure Step 4)

Figure Step 4

Step 5

Click the View menu. It should read SE Isometric. This will pull down the list of the predefined views as shown in the figure. (Figure Step 5)

Figure Step 5

Step 6

Enable Top to change the current view of the model to the Top. (Figure Step 6A and 6B)

Figure Step 6A

Figure Step 6B

Step 7

Pull down the View menu and set the current view to SE Isometric. (Figure Step 7A and 7B)

Figure Step 7A

Figure Step 7B

Step 8

Click the Visual Style menu and in the pull down list, set the current visual style to 2D Wireframe. (Figure Step 8A and 8B)

Figure Step 8A

Figure Step 8B

Step 9

Click the Visual Style menu and in the pull down list, set the current visual style to Conceptual. (Figure Step 9A and 9B)

Figure Step 9A

Figure Step 9B

Step 10

Click the small dash on the left side of the menu to pull down the menu. Enable Navigation Bar. The Navigation Bar will display on the right side of the Graphic window as shown in the figure. (Figure Step 10A and 10B)

Figure Step 10A

Figure Step 10B

Step 11

Click the small arrow located at bottom right corner of the Navigation Bar to pull down its menu. Ensure that all six item are enabled as shown in the figure. (Figure Step 11)

Figure Step 11

Step 12

Click the small arrow again located at the bottom of the Navigation Bar to pull down its menu. Click the Docking positions item to display the flyout menu. Ensure the enabled items match the figure. (Figure Step 12)

Figure Step 12

Step 13

Open the Options dialogue box using the OPTIONS command. Enable the All other visual styles item under the Display the ViewCube, as shown in the figures. Click OK to close the dialogue box. (Figure Step 13A and 13B)

Figure Step 13A

Figure Step 13B

Step 14

Click the small dash on the left side of the menu to pull down the menu. Enable ViewCube. The ViewCube will display on the right side of the Graphic window, as shown in the figure. (Figure Step 14A and 14B)

Figure Step 14A

Figure Step 14B

Step 15

Save and close the drawing.

ViewCube is a valuable AutoCAD 3D tool that provides visual feedback of the current orientation of the model and a very quick and effective method of changing your viewpoint of the model. See Figure 10-3.

ViewCube can be used to restore and define the Home view of a model, switch between views of the model, projection modes and change its interactive behavior and appearance.

Figure 10-3
ViewCube

WORK ALONG: Using ViewCube

Step 1

Open the drawing: AutoCAD 3D Workalong 10-1. (Figure Step 1)

Figure Step 1

Step 2

Click the small dash on the left side of the Viewport Controls menu. Ensure that ViewCube and Navigation Bar are enabled as shown in the figure. (Figure Step 2)

Figure Step 2

Step 3

The Graphic window should appear similar to the figure. (Figure Step 3)

Figure Step 3

Step 4

Ensure that the current view is set to SE Isometric.

Step 5

Click the arrow icon located on the lower right side of ViewCube. (Figure Step 5)

Figure Step 5

Step 6

In the pull-down menu, click Set Current View as Home. (Figure Step 6)

Figure Step 6

Step 7

Click the arrow again and click ViewCube Settings (Figure Step 7)

Figure Step 7

Step 8

Set the ViewCube Settings dialogue box as shown in the figure. (Figure Step 8)

Figure Step 8

Step 9

Move the cursor onto the top of ViewCube. When it turns blue, click it. The solid model’s current view will change to the Top view. (Figure Step 9A and 9B)

Figure Step 9A

Figure Step 9B

Step 10

Click the Home icon on ViewCube. It is the small house in the upper left corner. The model will now display the home view. For this model, it is SE Isometric. (Figure Step 10A and 10B)

Figure Step 10A

Figure Step 10B

Step 11

Using what you just learned, change the current view to Front. (Figure Step 11)

Figure Step 11

Step 12

Change the current view to Right. (Figure Step 12)

Figure Step 12

Step 13

Change the current view to the Home view. (Figure Step 13)

Figure Step 13

Step 14

Save and close the drawing.

USER TIP: ViewCube’s settings can also be adjusted in the Options dialogue box. See figure below.

Key Principles

The AutoCAD 3D book was written with competency based modules. What that means is that you have not completed each module until you have mastered it. The Competency Test module contains multiple choice questions and a comprehensive lab exercise to test your mastery of the set of modules that you completed. There are no answers or keys supplied in a Competency Test module since it is meant to be checked by your instructor. If there are any parts of this module that you have trouble completing, you should go back and reread the module or modules containing the information that you are having trouble with. If necessary, redo as many lab exercises required until you fully understand the material.

If you are completing this book:

• Without the aid of an instructor, complete the written test and the lab exercise.
• In a classroom with an instructor, the instructor will give instructions on what to do after this module has been completed.

Multiple Choice Questions

Select the BEST answer.

1. Where would the UCS plane be located if you used the Object UCS icon to select the current UCS?
   1. It would lie perpendicular to the plane the object selected was on.
   2. It would be on the WCS.
   3. It would lie parallel with the current view.
   4. It would lie on the plane that the selected object was on.
   5. It would lie perpendicular to the WCS.
2. What type of axis must you select to mirror a 3 dimensional object?
   1. level
   2. plane
   3. line
   4. circle
   5. point.
3. What command is used to polar array an object in 3D space?
   1. 3DARRAY
   2. ARRAY
   3. REVOLVE
   4. ROTATE
   5. 3DORBIT
4. What is the Z-axis array called in a 3D array?
   1. Level
   2. Axis
   3. Row
   4. Elevation
   5. Column
5. On what axis will the row be on in a 3D ARRAY?
   1. X
   2. Both the X and Y
   3. Z
   4. In the negative Z direction
   5. Y
6. How many degrees apart are the XYZ axis in a 2 dimensional isometric drawing?
   1. 60
   2. 90
   3. 120
   4. 180
   5. 360
7. How must a model be constructed if you want to view it in hidden mode using the VSCURRENT command? Choose the BEST answer.
   1. As a solid model.
   2. As a 3D wireframe.
   3. As a 2D wireframe.
   4. As a surface model.
   5. As either a surface or solid model.
8. What is the current visual style shown in Figure 11-1?
   1. 2D wireframe
   2. 3D wireframe
   3. Hidden
   4. Flat
   5. Gouraud
9. What is the current visual style shown in Figure 11-2?
   1. 2D wireframe
   2. 3D wireframe
   3. Hidden
   4. Flat
   5. Gouraud
10. What type of axis must you select to rotate a 3 dimensional object?
    1. level
    2. plane
    3. line
    4. circle
    5. point

Figure 11-1

Figure 11-2

Lab Exercise 11-1 OPEN BOOK

Step 1

On layer: Model, draw a wireframe model of the object shown in the multiview drawing. Set the current view to SE Isometric. (Figure Step 1A, 1B, 1C, and 1D)

Figure Step 1A
Wireframe Model

Figure Step 1B
Dimensioned Multiview Drawing

Figure Step 1C
Solid Model

Figure Step 1D
Solid Model

Step 2

Mirror the original model so that the mirrored copy lies on top of the existing model as shown in the figure. (Figure Step 2)

Figure Step 2

Step 3

Rotate the model 90 degrees as shown in the figure. Note the location of the WCS in relation to the model, after the rotation. (Figure Step 3)

Figure Step 3

Step 4

Move the model to locate the front corner on the WCS. (Figure Step 4)

Figure Step 4

Step 5

Array the model to match the figure. Keep the location of the WCS in mind when you are executing the array. (Figure Step 5)

Figure Step 5

Step 6

On layer: Construction, draw a line from absolute coordinates X20,Y100,Z0 to the absolute coordinates X-5,Y100,Z0. (Note that X is negative 5). Before you draw it, ensure that the current UCS is World and keep in mind that the coordinates are absolute so do not use an @.

Step 7

Copy, rotate and locate one of the models at the end of the line you drew in Step 6. Locate it at the absolute coordinates X-5,Y100,Z0 (Note that X is negative 5) as shown in the figure. (Figure Step 7A and 7B)

Figure Step 7A

Figure Step 7B

Step 8

Array the model as shown in the figure. (Figure Step 8)

Figure Step 8

Step 9

Your complete model should match the figure. ( figure Step 9)

Figure Step 9

Step 10

Save and close the drawing.

Surface Models

A surface model is a 3D model with all of its outer surfaces covered with a thin coating. Think of it as an empty box with a balloon skin. All the sides that define its shape are covered but it is hollow on the inside. Unlike a solid model, the volume, weight, and centre of gravity of a surface model cannot be calculated by AutoCAD. Solid modeling is taught in Modules 17 to 31.

There are many reasons why surface models are constructed rather than solid models. A surface model can be used to create objects that have complex curved shapes which are difficult to construct as a solid models. For industries such as the automobile, aircraft, and ship design, surfaces are used as a crucial part of their CAD design. For 3D mapping, surface meshes are used to define the 3D physical shape of the earth.

Surface Types

A surface can be either created with a face or a mesh or a combination of the two. A surface face is a good method to create simple surfaces while a surface mesh works for all surfaces including complex and curved surfaces. Figure 12-1 shows a model covered with a surface mesh. Faces and meshes can be combined, on the same model, when surfacing a model by creating some of the surfaces with faces and some with meshes. Once a model is surfaced, it can be shaded as shown in Figure 12-2.

Figure 12-1
Model with Surface Mesh

Figure 12-2
Shaded Surfaced Model

USER TIP: Although a model can be created with surfaces alone, it is much easier to construct it as a wireframe model first. Draw the wireframe on layer Model and when it is complete, create the surfaces and then freeze layer Model.

Wireframe Model                                                                      Surfaced Model

WORK ALONG: Inserting Surface Faces

Step 1

Using the NEW command, start a new drawing using template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 12-1.

Step 3

Set the current UCS to World. Enter the UNITS command and in the Units dialogue box, set the Insertion Units to Inches. Using the INSERT command, insert the block:

AutoCAD 3D Lab 01-2 at the coordinates 0,0,0. Explode the block and set the current view to SE Isometric. (Figure Step 3)

Figure Step 3

Step 4

Change the layer of all wireframe lines to layer: Model. (Figure Step 4)

Figure Step 4

Step 5

On layer: Construction, draw the construction lines to help you insert the surfaces. Keep in mind that the maximum number of sides that a face can be bound by is 4. Draw the lines on all six sides. (Figure Step 5)

Figure Step 5

Step 6

Set layer: Surface Face as the current layer. Enter the 3DFACE command, as shown below, to place a surface face on the wireframe model. Ensure you snap to the endpoints of the wireframe lines. (Figure Step 6)

Figure Step 6

Command: 3DFACE

Specify first point or [Invisible]: (end) P1

Specify second point or [Invisible]: (end) P2

Specify third point or [Invisible] <exit>: (end) P3

Specify fourth point or [Invisible]: (end) P4

(The surface face is defined by snapping to endpoints of existing wireframe lines. Pick points moving around the surface. Do not crisscross.)

Command:

Step 7

Enter the 3DFACE command as shown below. In this command, insert the common edges on the same plane as invisible. The figure shows the two edges (marked with an I) that should be inserted as invisible. (Figure Step 7)

Figure Step 7

Command: 3DFACE

Specify first point or [Invisible]: (end) P5

Specify second point or [Invisible]: (end) P6

Specify third point or [Invisible] <create three-sided face>: I

(You want the last edge to be invisible.)

Specify third point or [Invisible] <exit>: (end) P7

Specify fourth point or [Invisible] <create three-sided face>: (end) P8

Specify third point or [Invisible] <create three-sided face>: I

(You want the last edge to be invisible.)

Specify third point or [Invisible] <exit>: (end) P9

Specify fourth point or [Invisible] <create three-sided face>: (end) P10

Specify fourth point or [Invisible] <create three-sided face>: (end) P11

Specify fourth point or [Invisible] <create three-sided face>: (end) P12

Specify fourth point or [Invisible] <create three-sided face>: (end) P13

Specify fourth point or [Invisible] <create three-sided face>: (end) P14

Specify fourth point or [Invisible] <create three-sided face>: (end) P15

Specify fourth point or [Invisible] <create three-sided face>: (end) P16

Specify third point or [Invisible] <exit>:

Command:

Step 8

To check the surfaces you just inserted, set the current visual style to Realistic as shown in the figure. (Figure Step 8)

Figure Step 8

Step 9

Change the current visual style to 3D Wireframe.

Step 10

Using the 3DFACE command, add faces to completely surface the model. Ensure that you apply faces on the back and bottom. Turn layers: Model and Construction off.

Step 11

Change the current visual style to Realistic. Using the 3DFORBIT command, ensure that the complete model is surfaced. (Figure Step 11A and 11B)

Figure Step 11A

Figure Step 11B

Step 12

Save and close the drawing.

Key Principles

Lab Exercise 12-1

Time allowed: 60 minutes.

Step 1

On layer: Model, draw a wireframe model of the object shown in the figures. (Figure Step 1A, 1B, and 1C)

Step 2

On layer: Surface Face, create surface faces on all surfaces including the back and bottom. Make all surface edges invisible.

Step 3

Freeze layers: Construction and Model.

Figure Step 1A
Dimensioned Multiview Drawing

Step 4

See the current visual style to Realistic. Using 3DFORBIT, check it for completeness.

Step 5

Set the Insertion Units, change the current UCS to World and check the model with the key.

Figure Step 1B Wireframe of Model SE Isometric View

Figure Step 1C
Shaded Model

Step 6

Save and close the drawing.

Lab Exercise 12-2

Time allowed: 40 minutes.

Step 1

Open the drawing: AutoCAD 3D Lab 05-2.

Step 2

Using the SAVEAS command, save the drawing with the name: AutoCAD 3D Lab 12-2.

Step 3

On layer: Surface 3, create surface faces on each side including the back and bottom. (Figure Step 3A and 3B)

Figure Step 3A
Wireframe Model

Figure Step 3B
Surfaced Model – Shaded

Step 4

Freeze layers: Construction and Model.

Step 5

See the current visual style to Realistic. Using 3DFORBIT, check it for completeness.

Step 6

Save and close the drawing.

Lab Exercise 12-3

Time allowed: 40 minutes.

Step 1

Open the drawing: AutoCAD 3D Lab 07-1.

Step 2

Using the SAVEAS command, save the drawing with the name: AutoCAD 3D Lab 12-3.

Step 3

On layer: Surface 2, create surface faces on each side including the back and bottom. Surface all of it with mesh surfaces. (Figure Step 3A and 3B)

Figure Step 3A
Wireframe Model

Figure Step 3B
Surfaced Model – Shaded

Step 4

When complete, freeze layers: Construction and Model.

Step 5

See the current visual style to Realistic. Using 3DFORBIT, check it for completeness.

Step 6

Save and close the drawing.

Geometry Defined Surface Meshes

Geometrically defined surface meshes use existing geometry that must be created before the surfaces. In almost all cases, the wireframe of the model is used as the existing geometry. There are four geometrically defined surface meshes that can be created in AutoCAD. They are the ruled surface, revolved surface, tabulated surface, and edge surface. The commands to create these meshes are RULESURF, REVSURF, TABSURF, and EDGESURF. The EDGESURF command is taught in Module 15.

To create a geometry defined surface mesh, start with the wireframe geometry and ensure that it is on its own layer. Surface the wireframe model on all sides, making sure that all exposed sides have a surface covering them. Think of the model as an object that must be made water tight.

Even the inside of a hole going through the model must have a surface applied on it. Place the surface meshes on their own layer. When the surfaced model is complete, freeze the layer containing the wireframe or the geometry leaving only the layer with the surface mesh displayed.

Ruled Surface

A ruled surface, inserted with the RULESURF command, is the most commonly used method to surface a model. To place a ruled surface, simply select two lines, a line and an arc, two arcs, or two circles to place the surface between. See Figure 13-1.

Figure 13-1
Ruled Surface

Revolved Surface

A revolved surface, inserted with the REVSURF command, is a surface created by revolving a profile around an axis. The profile can be a line, arc, circle, or an open or closed 2D polyline or 3D polyline. See Figure 13-2. The axis must be a line or an open 2D or 3D polyline. If a polyline is used as the axis, the REVSURF command will simply use a straight line between the start point and end point of the polyline.

Figure 13-2
Revolved Surface

Tabulated Surface

A tabulated surface, inserted with the TABSURF command, is a surface created by projecting a profile along a path. The profile defines the surface of the mesh as it follows the path. See Figure 13-3. The profile can be a line, arc, circle, ellipse, or an open or closed 2D or 3D polyline. The path can be a line or a polyline. If a polyline is used as the axis, the TABSURF command will simply use a straight line between the start point and end point of the polyline. The surface is drawn starting at the point on the profile closest to the point selected in the command.

Figure 13-3
Tabulated Surface

Setting the Mesh Density

The mesh density represented by the lines, circles, or arcs that make the rows and columns of the surface mesh are controlled with the system variables SURFTAB1 and SURFTAB2. On flat surfaces, the density of the mesh is not that important but with curved or irregular shaped surfaces, the density is very important since the higher the setting, the more segments are used when creating circles and arcs. If the mesh is not dense enough, small gaps will be left where a curved surface meets a flat surface. See Figure 13-4.

Figure 13-4
SURFTAB Settings

AutoCAD Command: RULESURF

The RULESURF command is used to create a rule surface between two existing edges.

Shortcut: none

SURFTAB1 = YES

SURFTAB2 = No Effect

Draw Pull-down

Mesh Ribbon

WORK ALONG: Inserting Ruled Surfaces

Step 1

Using the NEW command, start a new drawing using template: 3D Layout Metric.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 13-1.

Step 3

Set the current layer to: Model and the current visual style to 2D Wireframe.

Step 4

Draw a wireframe model of the multiview drawing. (Figure Step 4A and 4B)

Figure Step 4A
Wireframe Model

Figure Step 4B
Dimensioned Multiview Drawing

Step 5

Set the system variable SURFTAB1 to 24 as shown below: Command: SURFTAB1

Enter new value for SURFTAB1 <8>: 24

Command:

Step 6

On layer: Construction, draw a line along the top edge of each side of the model. (Figure Step 6)

Figure Step 6

Step 7

Set layer: Surface 1 as the current layer. Enter the RULESURF command, as shown below, to insert a ruled surface. (Figure Step 7A and 7B)

Command: RULESURF

Current wire frame density: SURFTAB1=24

Select first defining curve: P1

Select second defining curve: P2

Command:

Figure Step 7A

Figure Step 7B

Step 8

Repeat the RULESURF command and insert surfaces all around the edge of the model. (Figure Step 8)

Figure Step 8

Step 9

Turn layer: Surface Off off and lock layers: Model and Construction. Select all of the surfaces inserted in Steps 7 and 8 and change their layer to: Surface Off. (Figure Step 9)

Figure Step 9

Step 10

Using what was just taught, insert ruled surfaces around the top of the object and inside of the hole as shown in the figure. (Figure Step 10).

Figure Step 10

Step 11

Change the layer of the surfaces inserted in Step 10 to layer: Surface Off.

Step 12

On layer: Construction, draw the construction lines on the top surface as shown in the figure. Ensure to snap to the endpoints of the lines and arcs. (Figure Step 12)

Figure Step 12

MUST KNOW: When using the RULESURF command, ensure that you select the objects closest to matching ends. If opposite ends are selected, the mesh will twist as shown in the figure.

Step 13

On layer: Surface 1, use the RULESURF command to insert the surfaces as shown in the figure. Change the surfaces the layer: Surface off. (Figure Step 13)

Figure Step 13

Step 14

On layer: Surface 1, use the RULESURF command to draw surfaces as shown in the figure. Change the layer of the surfaces to layer: Surface off. (Figure Step 14)

Figure Step 14

Step 15

On layer: Construction, draw a 180 degree arc on the top half of the circle. Ensure that you snap to the quads of the circle. To do that, ensure to locate the UCS on the same plane as the circle. (Figure Step 15)

Figure Step 15

Step 16

On layer: Surface 1, insert a ruled surface between the arcs. (Figure Step 16)

Figure Step 16

Step 17

Change the layer of the surface that you just drew to layer: Surface Off.

Step 18

Draw two construction lines and a construction arc on the bottom half of the circle. (Figure Step 18)

Figure Step 18

Step 19

On layer: Surface 1, insert a ruled surface. (Figure Step 19)

Figure Step 19

Step 20

On layer: Surface 1, insert the ruled surfaces as shown in the figure. (Figure Step 20)

Figure Step 20

Step 21

Change the layer of the existing surfaces to layer: Surface 1 until your model matches the figure. (Figure Step 21)

Figure Step 21

Step 22

Copy the surfaces from the front side of the model to back side. (Figure Step 22)

Figure Step 22

Step 23

Using what was just taught, complete surfacing the model. Ensure to surface the bottom of the model. When complete, change all the surfaces from layers: Surface off to Surface 1.

Step 24

Turn off all the layers except layer: Surface 1 and the model should appear as shown in the figure. (Figure Step 24)

Figure Step 24

Step 25

Set the current visual style to Realistic. (Figure Step 25)

Figure Step 25

Step 26

Save and close the drawing.

AutoCAD Command: REVSURF

The REVSURF command is used to create a surface of revolution by revolving an existing profile around an axis.

Shortcut: none

SURFTAB1 = YES

SURFTAB2 = YES

Draw Pull-down

Mesh Ribbon

WORK ALONG: Inserting Revolved Surfaces

Step 1

Using the NEW command, start a new drawing using template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 13-2. (Figure Step 2)

Figure Step 2
Dimensioned Multiview Drawing

Step 3

Set the current layer to: Pline and the current visual style to 2D Wireframe.

Step 4

Change the current view to SE Isometric and the current UCS to Right.

Step 5

Using the multiview drawing as a reference, draw the right side cross section of the solid part of the object. (Figure Step 5)

Figure Step 5

Step 6

On layer: Construction, draw a line, of any length, from 0,0,0 along the X axis. Enable ortho mode to draw it faster. This is the centre of the model and will be used as the axis for the revolution. (Figure Step 6)

Figure Step 6

Step 7

Using the PEDIT command, as shown below, convert the lines of the model to a closed polyline.

Command: PE

Select polyline or [Multiple]:

(Select one line of the model.)

Object selected is not a polyline

Do you want to turn it into one? <Y>

(Press Enter to accept the default.)

Enter an option [Close/Join/Width/Edit vertex/Fit/Spline/Decurve/Ltype gen/Undo]: J

(J for Join.)

Select objects: ALL

13 found

Select objects:

11 segments added to polyline

Enter an option [Open/Join/Width/Edit vertex/Fit/Spline/Decurve/Ltype gen/Undo]:

Command:

Step 8

To ensure that you have successfully created a closed polyline, open the Properties window and select the polyline. The object type should read Polyline, all the objects should show as part of the polyline and the Closed property should indicate Yes. (Figure Step 8)

Figure Step 8

Step 9

Set the system variable SURFTAB1 to 64 and SURFTAB2 to 24 as shown below.

Command: SURFTAB1

Enter new value for SURFTAB1 <6>: 64

Command: SURFTAB2

Enter new value for SURFTAB2 <6>: 24

Command:

Step 10

Change the current layer to layer: Surface 1 and enter the REVSURF command as shown below. After you complete the command, your model should appear as shown in the figure. (Figure Step 10)

Command: REVSURF

Current wire frame density: SURFTAB1=64 SURFTAB2=24

Select object to revolve

(Select the closed polyline.)

Select object that defines the axis of revolution:

(Select the axis line.)

Specify start angle <0>:

(Accept the default of 0.)

Specify included angle (+=ccw, -=cw) <360>:

(Accept the default of 360.)

Command:

Figure Step 10

Step 11

Turn layers: Construction and Pline off and set the current visual style to Realistic.

Step 12

Using the 3DFORBIT command, orbit the model and look at all sides. (Figure 12A and 12B)

Figure Step 12A
SE Isometric View

Figure Step 12B
SE Isometric View

Step 13

Save and close the drawing.

AutoCAD Command: TABSURF

The TABSURF command is used to create a surface mesh moving a profile along a path. Shortcut: none

SURFTAB1 = YES

SURFTAB2 = No Effect

Draw Pull-down

Mesh Ribbon

WORK ALONG: Inserting Tabulated Surfaces

Step 1

Using the NEW command, start a new drawing using template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 13-3.

Step 3

Set the current visual style to 2D Wireframe, the current view to SE Isometric, and the current UCS to World.

Step 4

Set layer: Construction as the current layer. Draw the model shown in the dimensioned model. These are the construction lines and arcs to be used to construct the model. When complete, your model will appear as shown in the figure. The length of the lines that appear dashed in the dimensioned model are not important since they are axis lines only. They are always drawn in the Z direction of the current UCS. They can be drawn any length as continuous linetype. (Figure Step 4A, 4B, and 4C)

Figure Step 4A Dimensioned Model SE Isometric View

Figure Step 4B
SE Isometric View

Figure Step 4C
Orbited View

Step 5

Set the current UCS to Front and then draw a model of the object shown in the dimensioned drawing. The drawing should appear as shown in the figure. Draw the model anywhere in model space. Its location is not important. (Figure Step 5A and 5B)

Figure Step 5A

Figure Step 5B

Step 6

Change the lines and arcs into two closed polylines using the PEDIT command. Check them using the Properties window. (Figure Step 6)

Figure Step 6

Step 7

On layer: Construction, draw in two construction lines from midpoint of the lines to find the exact centre of the object. (Figure Step 7)

Figure Step 7

Step 8

Make three additional copies of the model and rotate them to lay on different UCS planes. Their location in 3D space is not important. (Figure Step 8)

Figure Step 8

Step 9

Your drawing should appear similar to the figure. (Figure Step 9)

Figure Step 9

Step 10

Copy the objects onto the construction lines. Ensure that the midpoint of the object (the intersections of the construction lines) aligns to the endpoints of the lines and arcs. (Figure Step 10)

Figure Step 10

Step 11

With the UCS located on the Front, SURFTAB1 set to 48 and layer: Surface 1 as the current layer, enter the TABSURF command, as shown below, to create the surface for the inside of the tube. (Figure Step 11)

Figure Step 11

Command: TABSURF

Current wire frame density: SURFTAB1=48

Select object for path curve:

(Select the inside polyline.)

Select object for direction vector:

(Select the construction axis line. Ensure you select it closer to the end where the object your are tabulating is located.)

Command:

Step 12

Set the current visual style to Realistic. (Figure Step 12)

Figure Step 12

Step 13

Using the TABSURF command, create the surface for the outside of the tube. (Figure Step 13)

Figure Step 13

Step 14

Enter the REVSURF command, as shown below, to construct the inside of the tube around the first corner. First change the layer of the straight tube surfaces constructed in Steps 11 to 13 to layer: Surface Off. (Figure Step 14)

Command: REVSURF

Current wire frame density: SURFTAB1=48 SURFTAB2=6

Select object to revolve:

(Select the inside polyline.)

Select object that defines the axis of revolution

(Select the axis line.)

Specify start angle <0>:

(Accept the default.)

Specify included angle (+=ccw, -=cw) <360>: -90

Command:

Figure Step 14

Step 15

Using what was just taught, construct the outside of the tube and change the layers of the surfaces until the model appear as shown in the figure. (Figure Step 15)

Figure Step 15

Step 16

Using what was just taught, complete the model. (Figure Step 16)

Figure Step 16

Step 17

Turn off layers: Model and Construction and your completed model will appear as shown in the figure. (Figure Step 17)

Figure Step 17

Step 18

Save and close the drawing.

Key Principles

Lab Exercise 13-1

Time allowed: 45 minutes.

Step 1

Draw a wireframe of the object shown in the figure. (Figure Step 1)

Figure Step 1
Dimensioned Multiview Drawing

Step 2

Pick appropriate mesh densities and on layer: Surface 2, create surface meshes on all surfaces including back and bottom. (Figure Step 2)

Figure Step 2
Completed Model SE Isometric View

Step 3

Freeze layers: Construction and Model.

Step 4

Set the current visual style to Realistic. Use the 3DORBIT command to check that the model is surfaced on all sides.

Step 5

Set the Insertion Units, change the current UCS to World and check the model with the key.

Step 6

Save and close the drawing.

Lab Exercise 13-2

Time allowed: 45 minutes.

Step 1

Open the drawing: AutoCAD 3D Lab 04-1.

Step 2

Save the drawing with the name: AutoCAD 3D Lab 13-2.

Step 3

On layer: Surface 5, create surface meshes on all surfaces including back and bottom. (Figure Step 3)

Step 4

Freeze layers: Construction and Model.

Step 5

Set the current visual style to Realistic. Use the 3DFORBIT command to check that the model is surfaced on all sides.

Figure Step 3 Completed Model SE Isometric View

Step 6

Save and close the drawing.

Lab Exercise 13-3

Time allowed: 45 minutes.

Step 1

Open the drawing: AutoCAD 3D Lab 08-1.

Step 2

Save the drawing with the name: AutoCAD 3D Lab 13-3.

Step 3

On layer: Surface 1, create surfaces on each side including back and bottom. (Figure Step 3)

Step 4

Freeze layers: Construction and Model.

Step 5

Set the current visual style to Realistic. Use the 3DFORBIT command to check that the model is surfaced on all sides.

Figure Step 3 Completed Model SE Isometric View

Step 6

Save and close the drawing.

Lab Exercise 13-4

Time allowed: 45 minutes.

Step 1

On layer: Pline, draw the cross section of the top half of the model on the right side UCS. (Figure Step 1A and 1B)

Figure Step 1A
Dimensioned Multiview Drawing

Figure Step 1B View Of a Cross Section to Revolve

Step 2

Create a surface revolution on layer: Surface 1. (Figure Step 2)

Figure Step 2 Complete Model SE Isometric View

Step 3

Freeze layers: Pline and Construction.

Step 4

Set the current visual style to Realistic. Use the 3DORBIT command to check that the model is surfaced on all sides.

Step 5

Set the Insertion Units, change the current UCS to World and check the model with the key.

Step 6

Save and close the drawing.

Drawing Complex Surface Meshes

When an irregular complex mesh cannot be drawn using a geometrically generated surface, the 3DMESH command can be used to create it. The 3DMESH command uses a grid made of XYZ coordinates to generate the surface mesh. This command is used extensively when creating 3D topographical maps. It is also used in automobile and airplane design.

WORK ALONG: Drawing 3D Surface Meshes

Step 1

Using the NEW command, start a new drawing using template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 14-1.

Step 3

Set layer: Model as the current layer.

Step 4

Set the current visual style to 2D Wireframe, the current UCS to World, and the current view to SE Isometric. (Figure Step 4)

Figure Step 4

Step 5

Draw a 5 X 4 grid as shown in the figure. Draw the grid lines 1 inch apart along both the X and Y axis. (Figure Step 5)

Figure Step 5

Step 6

Set layer: Surface 1 as the current layer and using Figure Step 6A as a reference, enter the 3D MESH command, as shown below, to create the 3D mesh. When complete, your drawing should appear as shown in the figure. (Figure Step 6A and 6B)

Figure Step 6A

4Figure Step 6BCommand: 3DMESH

Enter size of mesh in M direction: 5

(5 columns in the X direction. Count the grid lines not the spaces.)

Enter size of mesh in N direction: 4

(4 rows in the Y direction. Count the grid lines, not the spaces.)

Specify location for vertex (0, 0): 0,0,0.2

(Enter the XYZ coordinates stating at bottom left corner which is X0Y0Z0.2. Then work up the Y axis to the top and then jump back down to X1,Y0.)

Specify location for vertex (0, 1): 0,1,0.5

(The 0.5 is entered here for clarity. If you enter .5 it will do the same thing.)

Specify location for vertex (0, 2): 0,2,0.4

Specify location for vertex (0, 3): 0,3,0.3

Specify location for vertex (1, 0): 1,0,0.1

Specify location for vertex (1, 1): 1,1,0.3

Specify location for vertex (1, 2): 1,2,0.6

Specify location for vertex (1, 3): 1,3,0.5

Specify location for vertex (2, 0): 2,0,0

Specify location for vertex (2, 1): 2,1,-0.2

Specify location for vertex (2, 2): 2,2,-0.3

Specify location for vertex (2, 3): 2,3,-0.5

Specify location for vertex (3, 0): 3,0,0.1

Specify location for vertex (3, 1): 3,1,0.2

Specify location for vertex (3, 2): 3,2,0.2

Specify location for vertex (3, 3): 3,3,0.2

Specify location for vertex (4, 0): 4,0,0.3

Specify location for vertex (4, 1): 4,1,0.7

Specify location for vertex (4, 2): 4,2,0.5

Specify location for vertex (4, 3): 4,3,0.4

Command:

Figure Step 6B

Step 7

Turn layer Model off and set the current visual style to: Realistic. Your model should appear similar to the figure. (Figure Step 7)

Figure Step 7

Step 8

Turn layer: Surface 1 off and layer: Model on. Set the current layer to: Model. With the UCS set to World, draw lines from the each grid vertex in the Z distance. See Figure Step 6A for the Z value. Be careful as some are positive and some are negative. When the Z is 0, you do not have to draw anything. For example, the line at X0Y0 should be drawn 0.2 inches in the positive Z direction. When complete, the model should appear as shown in figure. (Figure Step 8)

Figure Step 8

Step 9

Set layer: Surface 2 as the current layer and enter the 3DMESH as shown below. (Figure Step 9)

Command: 3DMESH

Enter size of mesh in M direction: 5

Enter size of mesh in N direction: 4

Specify location for vertex (0, 0): (end) P1

(With osnap enabled, snap to the end of the Z line. You may have to zoom in to ensure you are snapping to the correct end of the line.)

Specify location for vertex (0, 1): (end) P2

Specify location for vertex (0, 2):(end) P3

Specify location for vertex (0, 3):(end) P4

Specify location for vertex (1, 0):(end) P5

Specify location for vertex (1, 1):(end) P6

(Continue until you complete the grid.)

Command:

Figure Step 9

Step 10

Set the current visual style to: Realistic. Your model should appear similar to the figure. (Figure Step 10)

Figure Step 10

Step 11

Save and close the drawing.

Regions

A region is a 2D solid and is created using a closed polyline, circle, ellipse or spline as the boundary. A region must lie on a 2D plane. See Figure 14-1.

Figure 14-1
A Region

While regions are not technically surfaces, they will shade and can be rendered, therefore, can be used to surface a model.

If the system variable DELOBJ is set to 1, AutoCAD will delete the closed object that was used as the boundary to create the region. In most cases, it is important for you to set this variable to 0 to retain the original object used to create the region.

AutoCAD Command: REGION

The REGION command is used to create a 2D solid within a closed object.

Shortcut: REG

Draw Toolbar

Draw Pull-down

Home Ribbon

AutoCAD Command: SUBTRACT

The SUBTRACT command is used to subtract one solid from another.

Shortcut: SU

Modeling Toolbar

Modify Pulldown

Home Ribbon

WORKALONG: Inserting and Subtracting Regions

Step 1

Using the NEW command, start a new drawing using template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 14-2. (Figure Step 2)

Figure Step 2
Dimensioned Multiview Drawing

Step 3

Set layer: Model as the current layer, the current view to SE Isometric, the current UCS to Top, and the current visual style to 2D Wireframe.

Step 4

Draw the wireframe model of the multiview drawing. (Figure Step 4)

Figure Step 4 Wireframe of Model – SE Isometric View

Step 5

Enter the DELOBJ system variable, as shown below, and set it 0. Command: DELOBJ

Enter new value for DELOBJ <1>: 0

Command: DELOBJ

Enter new value for DELOBJ <0>:

Command:

Step 6

Move the UCS to lie on top of the model as shown in the figure. Ensure that the positive Z axis is up and it is located at the centre of the circle. (Figure Step 6)

Figure Step 6

Step 7

Using what you learned earlier, use the PEDIT command to convert the lines and arcs to closed polylines. Check the objects with the Properties window to ensure that they are closed. (Figure Step 7)

Figure Step 7

Step 8

Delete all of the objects except the circles on the bottom of the model and then copy the plines you just created to the bottom. (Figure Step 8)

Figure Step 8

Step 9

Set layer: Surface 1 as the current layer and enter the REGION command, as shown below, to create regions for the five closed objects on top of the model.

Command: REGION

Select objects: 1 found

(Select each object, by picking them one at a time.)

Select objects: 1 found, 2 total

Select objects: 1 found, 3 total

Select objects: 1 found, 4 total

Select objects: 1 found, 5 total

Select objects:

5 loops extracted.

5 Regions created.

Command:

Step 10

Set the current visual style to: Realistic. Your model should appear as shown in the figure. (Figure Step 10)

Figure Step 10

Step 11

Using the REGION command, insert a region using the outside closed polyline. (Figure Step 11)

Figure Step 11

Step 12

Using the SUBTRACT command, subtract the five inner regions that you created in Step 9 from the region you created in Step 11. (Figure Step 12)

Command: SUBTRACT

Select solids and regions to subtract from ..

Select objects: 1 found

(Select the large region.)

Select objects:

(Press Enter to indicate you have finished selecting.)

Select solids and regions to subtract ..

Select objects: 1 found

(Select each of the five smaller regions one at a time.)

Select objects: 1 found, 2 total

Select objects: 1 found, 3 total

Select objects: 1 found, 4 total

Select objects: 1 found, 5 total

Select objects:

Command:

Figure Step 12

Step 13

Ensure that layer: Surface Off is off and then change the layer of the region you just created to layer: Surface Off. Your model will now appear as shown in the figure. (Figure Step 13)

Figure Step 13

Step 14

Click the UCS Origin icon and then snap to the centre of the circle on the bottom of the object. (Figure Step 14)

Figure Step 14

Step 15

Click the Rotate X Axis UCS icon on the UCS toolbar and rotate it 180 degree rotation. This will rotate the UCS so that the positive Z direction is pointing down. (Figure Step 15)

Figure Step 15

Step 16

Using the 3DORBIT command, rotate the model around about 180 degrees and then using what you learned in Steps 10 to 12, insert the regions on the bottom. Subtract the inner regions as you did before. (Figure Step 16)

Figure Step 16

Step 17

Change the layer of the regions to layer: Surface Off and then using the RULESURF command, create surfaces on the edges and holes in the model. Create the surfaces on layer: Surface 1. (Figure Step 17)

Figure Step 17

Step 18

Turn layers: Model and Construction off and change the layer of the regions to layer: Surface 1. Your completed model should appear as shown in the figure. Use the 3DORBIT command to check that the complete model is surfaced. (Figure Step 18)

Figure Step 18

MUST KNOW: A region is a two-dimensional solid created within a closed object. Regions can only be created within closed plines, circles, ellipses and splines. The complete region must lay on one plane. A region is actually a 2D solid.While regions are not technically surfaces, they will shade and can be rendered, therefore, can be used to surface a model.If the system variable DELOBJ is set to 1, AutoCAD will delete the closed object that was used to create the region. In most cases, it is important for you to set this variable to 0 to retain your original wireframe object used to create the region.

Key Principles

Lab Exercise 14-1

Time allowed: 60 minutes.

Step 1

On layer: Model, draw the grid shown below. The grid lines are an equal distance apart. (Figure Step 1A and 1B)

Figure Step 1A
Grid in SE Isometric View

Figure Step 1B
Grid in Top View

Step 2

On layer: Surface 2, draw a 3D mesh on the grid using the 3D MESH command. The Z values are displayed at each vertex in Figure Step 1B. Set the current visual style to Realistic. It should appear as shown in the figure. (Figure Step 2)

Figure Step 2

Step 3

Set the current visual style to 3D Wireframe. Turn layer Surface 2 off and on layer: Model, draw lines representing the Z coordinates. (Figure Step 3)

Figure Step 3

Step 4

On layer: Surface 3, draw a 3D mesh on the grid using the 3D MESH command and snapping to ends of the Z coordinates. Set the current visual style to Realistic. (Figure Step 4)

Figure Step 4

Step 5

Turn layer: Model off and the completed mesh should appear as shown in the figure. (Figure Step 5)

Figure Step 5

Step 6

Set the Insertion Units, change the current UCS to World and check the model with the key.

Step 7

Save and close the drawing.

Lab Exercise 14-2

Time allowed: 40 minutes.

Step 1

Draw a wireframe model of the object. (Figure Step 1A and 1B)

Figure Step 1A
Completed Surfaced Model

Figure Step 1B
Dimensioned Wireframe Model

Step 2

Use the 2D ARRAY command to speed the model construction.

Step 3

On layer: Surface 1, create regions for the top and bottom of the model.

Step 4

On layer: Surface 1, create ruled surfaces for the remainder of the surfaces. Ensure that the complete model is surfaced.

Step 5

Set the visual style to: Realistic.

Step 6

Freeze layers: Construction and Model.

Step 7

Using the 3DORBIT command, check the model for completeness

Step 8

Set the Insertion Units, change the current UCS to World and check the model with the key.

Lab Exercise 14-3

Time allowed: 30 minutes.

Step 1

Open the drawing: AutoCAD 3D Lab 03-2.

Step 2

Save the drawing with the name: AutoCAD 3D Lab 14-3.

Step 3

On layer: Surface 1, create regions and surfaces on all sides and holes. (Figure Step 3)

Figure Step 3
Completed Surfaced Model

Step 4

Set the visual style to Realistic.

Step 5

Freeze layers: Construction and Model.

Step 6

Using the 3DORBIT command, check the model for completeness

Step 7

Save and close the drawing.

Lab Exercise 14-4

Time allowed: 50 minutes.

Step 1

Open the drawing: AutoCAD 3D Lab 09-3.

Step 2

Save the drawing with the name: AutoCAD 3D Lab 14-4.

Step 3

On layer: Surface 2, create regions and surfaces on all sides and holes. (Figure Step 3)

Figure Step 3
Completed Surfaced Model

Step 4

Set the visual style to: Realistic.

Step 5

Freeze layers: Construction and Model.

Step 6

Using the 3DORBIT command, check the model for completeness

Step 7

Save and close the drawing.

3D Polylines

Since the release of AutoCAD 14, polylines created with the PLINE command have been created as lightweight polylines. Sometimes called a 2D polylines, shown in Figure 15-1, lightweight polyline are greatly improved over the older heavyweight or 3D polylines. A 2D polyline must lay on a single plane.

A 3D polyline is created with the 3DPOLY command using XYZ coordinates to locate each of the vertices. See Figure 15-2. A 3D polyline is not restricted to lay on the same plane. It requires a larger part of the drawings database compared to a 2D polyline. For that reason, use 3D polylines only when absolutely required in 3D modeling. 3D polylines must be constructed with lines only and cannot contain arcs or be given a width.

Figure 15-1
2D polylines

Figure 15-2
3D polylines

AutoCAD Command: 3DPOLY

The 3DPOLY command is used to create 3D polylines.

Shortcut: none

Draw Pull-down

AutoCAD Command: EDGESURF

The EDGESURF command is used to create a surface mesh by selecting four drawing objects. The drawing objects can be lines, arcs, 2D polylines, and 3D polylines.

Shortcut: none

Mesh Ribbon

Draw Pull-down

WORK ALONG: Surfacing Models Using 3D Polylines and Edge Surfaces

Step 1

Open the drawing: AutoCAD 3D Workalong 14-1.

Step 2

Using the SAVEAS command, save the drawing with the name: AutoCAD 3D Workalong 15-1.

Step 3

Turn off all layers except layer: Model.

Step 4

Set the current visual style to 2D Wireframe, the current UCS to World and the current view to SE Isometric. Your model should appear as shown in the figure. (Figure Step 4)

Figure Step 4

Step 5

Set layer: 3D Pline as the current layer. Enter the 3DPOLY command, as shown below, to draw 3D polylines between all of the Z coordinates on the grid in both the X and the Y direction. (Figure Step 5)

Command: 3DPOLY

Specify start point of polyline: (end) P1

Specify endpoint of line or [Undo]: (end) P2

Specify endpoint of line or [Undo]: (end) P3

Specify endpoint of line or [Undo]: (end) P4

Specify endpoint of line or [Close/Undo]:

Command: 3DPOLY

Specify start point of polyline: (end) P5

Specify endpoint of line or [Undo]: (end) P6

Specify endpoint of line or [Undo]: (end) P7

Specify endpoint of line or [Undo]: (end) P8

Specify endpoint of line or [Close/Undo]:

Command:

Figure Step 5

Step 6

Continue drawing the remainder of the 3D polylines on the Y axis. (Figure Step 6)

Figure Step 6

Step 7

Draw 3D polylines between all the Z coordinates in the X direction until you complete the grid. (Figure Step 7)

Figure Step 7

Step 8

Turn layer: Model off and your model should appear as shown in the figure. Using the EXPLODE command and a window, explode the 3D plines to convert them into lines. (Figure Step 8)

Figure Step 8

Step 9

Change the view to Top. (Figure Step 9)

Figure Step 9

Step 10

Set layer: Surface 1 as the current layer. Enter the 3DMESH command, as shown below, to create the mesh. (Figure Step 10)

Command: 3DMESH

Enter size of mesh in M direction: 5

Enter size of mesh in N direction: 4

Specify location for vertex (0, 0): (end) P1

Specify location for vertex (0, 1): (end) P2

Specify location for vertex (0, 2): (end) P3

Specify location for vertex (0, 3): (end) P4

Specify location for vertex (1, 0): (end) P5

Specify location for vertex (1, 1): (end) P6

Specify location for vertex (1, 2): (end) P7

Specify location for vertex (1, 3): (end) P8

(Continue to cover the complete mesh.)

Command:

Figure Step 10

Step 11

Set the current visual style to Realistic and the current view to SE Isometric. (Figure Step 11)

Figure Step 11

Step 12

Set the current visual style to 2D Wireframe and turn layer: Surface 1 off. You will only see the 3D polylines. (Figure Step 12)

Figure Step 12

Step 13

Set the system variables SURFTAB1 to 6 and SURFTAB2 to 6.

Step 14

On layer: Surface 4, use the EDGESURF command, as shown below, to create a surface mesh on one grid square. (Figure Step 14)

Command: EDGESURF

Current wire frame density: SURFTAB1=6 SURFTAB2=6

Select object 1 for surface edge: P1

Select object 2 for surface edge: P2

Select object 3 for surface edge: P3

Select object 4 for surface edge: P4

Command:

Figure Step 14

Step 15

Set the current visual style to Realistic. (Figure Step 15)

Figure Step 15

Step 16

On layer: Surface 4, using the EDGESURF command, create surfaces in all grid squares to cover the model. When complete, the model will appear as shown in the figure. (Figure Step 16)

Figure Step 16

Step 17

Save and close the drawing.

Modifying the Appearance of Surface Meshes

There are several system variables that can be used to modify or change the appearance of existing surface meshes or changing their mesh density. The PEDIT command and SURFV, SURFU, SURFTYPE, and SPLFRAME system variables are used to smooth and change the setting for the appearance of and mesh density of 3D meshes. If the desired results cannot be obtained using these system variables, it is sometime easier and faster to erase the surface and construct it again using a smaller base grid.

WORK ALONG: Modifying the Appearance of Surface Meshes

Step 1

Open drawing: AutoCAD 3D Workalong 15-1. Using the SAVEAS command, save the drawing with the name: AutoCAD 3D Workalong 15-2.

Step 2

Turn off all layers except layer: Surface 1. Set the current visual style to Realistic, the current UCS to World and the current view to SE Isometric. (Figure Step 2)

Figure Step 2

Step 3

Set the current visual style to 3D Wireframe. (Figure Step 3)

Figure Step 3

Step 4

Enter the commands shown below and your model will appear as shown in the figure. (Figure Step 4)

Command: SURFV

Enter new value for SURFV <6>: 12

Command: SURFU

Enter new value for SURFU <6>: 24

Command: PEDIT

Select polyline or [Multiple]:

(Select the mesh.)

Enter an option [Edit vertex/Smooth surface/Desmooth/Mclose/Nclose/Undo]: S

Generating segment 2… Command: REGEN

REGEN Regenerating model.

Command:

Figure Step 4

Step 5

Enter the commands shown below. The model should display as it was when you started this exercise. (Figure Step 5)

Command: SPLFRAME

Enter new value for SPLFRAME <0>: 1

Command: REGEN Regenerating model.

Command:

Figure Step 5

Step 6

Enter the commands shown below and your model will display as shown in the figure. (Figure Step 6)

Command: SPLFRAME

Enter new value for SPLFRAME <1>: 0

Command: REGEN

Regenerating model

Command:

Figure Step 6

Step 7

Enter the commands shown below and your model will display as shown in the figure. (Figure Step 7)

Command: SURFTYPE

Enter new value for SURFTYPE <6>: 5

Command: PEDIT

Select polyline or [Multiple]:

(Select the mesh.)

Enter an option [Smooth surface/Desmooth/MOpen/MClose/NOpen/NClose/Undo]: S

Command:

Figure Step 7

Step 8

Enter the commands shown below and your model will display as shown in the figure. (Figure Step 8)

Command: SURFTYPE

Enter new value for SURFTYPE <5: 8

Command: PEDIT

Select polyline or [Multiple]:

(Select the mesh.)

Enter an option [Smooth surface/Desmooth/MOpen/MClose/NOpen/NClose/Undo]: S

Command:

Figure Step 8

Step 9

Set the current visual style to Realistic. (Figure Step 9)

Figure Step 9

Step 10

Save and close the drawing.

Key Principles

Lab Exercise 15-1

Time allowed: 3 hours.

Step 1

In this lab exercise, you will be creating a surface mesh on a plot of land that is 2500 X 2500 feet. There is an exiting 100 ft. road on the south side of the property. (Figure Step 1)

Figure Step 1

Step 2

Start a new drawing, using the template 3D Layout English. Insert the block: AutoCAD 3D Lab 15-1. Explode the block.

Step 3

Change the layer of all objects to layer: Model. (Figure Step 3)

Figure Step 3

Step 4

Change the current view to SE Isometric. (Figure Step 4)

Figure Step 4

Step 5

The 2D grid is located at sea level or Z=zero and is divided equally every 100 ft.

Step 6

On the layer: 3D Pline, draw 3D polylines between the top of each of the Z coordinate lines to construct a digital terrain model of the property as shown below. Try rotating the grid and lines to different positions to find the best view to insert the 3D polylines. (Figure Step 6)

Figure Step 6

Step 7

Turn off all layers except layers: 3D Pline and Surface 2.

Step 8

Change the view to Top. (Figure Step 8)

Figure Step 8

Step 9

Set layer: Surface 2 as the current layer. Using the EXPLODE command and a window, explode the 3D plines to convert them into lines.

Step 10

Using the 3DMESH command, draw a mesh by snapping to each of the 625 endpoints. Ensure to select the points in the correct sequence and zoom in to select very accurately. If an error is made, start over again. This will require about 30 minutes of uninterrupted work. Turn layer: 3D Pline off. Set the current view to SE Isometric and the current visual style to Realistic. (Figure Step 10)

Figure Step 10

Step 11

Save and close the drawing.

The AutoCAD 3D book was written with competency based modules. What that means is that you have not completed each module until you have mastered it. The Competency Test module contains multiple choice questions and a comprehensive lab exercise to test your mastery of the set of modules that you completed. There are no answers or keys supplied in a Competency Test module since it is meant to be checked by your instructor. If there are any parts of this module that you have trouble completing, you should go back and reread the module or modules containing the information that you are having trouble with. If necessary, redo as many lab exercises required until you fully understand the material.

If you are completing this book:

• Without the aid of an instructor, complete the written test and the lab exercise.
• In a classroom with an instructor, the instructor will give instructions on what to do after this module has been completed.

Multiple Choice Questions

Select the BEST answer.

1. In a surface mesh, what is the intersection of a column and a row called?
   1. Crossing
   2. Point
   3. Junction
   4. Corner
   5. Vertex
2. What command creates a surface mesh by selecting 4 edges?
   1. EDGE
   2. EDGESURF
   3. REVSURF
   4. TABSURF
   5. RULESURF
3. What system variable(s) controls the surface mesh density of the M and N directions when a surface mesh is smoothed with the PEDIT command?
   1. SURFMESH
   2. SURFTAB1 and SURTAB2
   3. SPLFRAME
   4. SURFV and SURFU
   5. SURFTYPE
4. What type of AutoCAD object is a two-dimensional solid created within a closed object? Choose the BEST answer.
   1. Wireframe
   2. Mesh
   3. Region
   4. Surface
   5. Solid
5. A mesh is defined by rows and columns. What are the columns called?
   1. M
   2. S
   3. R
   4. C
   5. N
6. What command creates a mesh from a path curve along a direction vector?
   1. 3DMESH
   2. EDGE
   3. 3DFACE
   4. REVSURF
   5. TABSURF
7. What system variable(s) controls the mesh density of a surface mesh when the mesh is created?
   1. SURFMESH
   2. SURFTAB1 and SURTAB2
   3. SPLFRAME
   4. SURFV and SURFU
   5. SURFTYPE
8. What command creates a surface face bounded by a minimum of three and a maximum of four edges?
   1. 3DMESH
   2. EDGE
   3. 3DFACE
   4. REVSURF
   5. TABSURF
9. What system variable(s) controls the display of splines and meshes that have been smoothed with the PEDIT command?.
   1. SURFMESH
   2. SURFTAB1 and SURTAB2
   3. SPLFRAME
   4. SURFV and SURFU
   5. SURFTYPE
10. What command creates an irregular complex surface mesh from a grid of XYZ coordinates?
    1. 3DMESH
    2. EDGE
    3. 3DFACE
    4. REVSURF
    5. TABSURF

Lab Exercise 16-1A OPEN BOOK

Step 1

On layer: Model, draw a wireframe model of the Base. (Figure Step 1)

Figure Step 1
Dimensioned Multiview Drawing of the Base

Step 2

On layer: Surface Base, surface the complete model. Use faces, meshes, regions, or a mixture of them. (Figure Step 2)

Figure Step 2
Surfaced Model of the Base

Step 3

Create a block of the model. Name it: AutoCAD 3D Lab 16-1A. Pick an appropriate location for 0,0,0. Make 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.

Lab Exercise 16-1B OPEN BOOK

Step 1

On layer: Model, draw a wireframe model of the Support. (Figure Step 1)

Figure Step 1
Dimensioned Multiview Drawing of the Support

Step 2

On layer: Construction, add any necessary construction objects that may help insert the model into the assembly.

Step 3

On layer: Surface Support, surface the complete model. Use faces, meshes, regions, or a mixture of them. (Figure Step 3)

Figure Step 3 Surfaced Model of the Support

Step 4

Create a block of the model. Name it:

AutoCAD 3D Lab 16-1B. Pick an appropriate location for 0,0,0. Make 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.

Lab Exercise 16-1C OPEN BOOK

Step 1

On layer: Model, draw a wireframe model of the Axel. (Figure Step 1)

Figure Step 1
Dimensioned Multiview Drawing of the Axle

Step 2

On layer: Construction, add any necessary construction objects that may help insert the model into the assembly.

Step 3

On layer: Surface Axel, surface the complete model. Use faces, meshes, regions, or a mixture of them. (Figure Step 3)

Figure Step 3
Surfaced Model of the Axle

Step 4

Create a block of the model. Name it:

AutoCAD 3D Lab 16-1C. Pick an appropriate location for 0,0,0. Make 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.

Lab Exercise 16-1D OPEN BOOK

Step 1

on layer Model, draw a wireframe model of the Wheel. (Figure Step 1)

Figure Step 1
Dimensioned Multiview Drawing of the Wheel

Step 2

On layer Construction, add any necessary construction objects that may help insert the model into the assembly.

Step 3

On layer Surface Wheel, surface the complete model. Use faces, meshes, regions, or a mixture of them. (Figure Step 3)

Figure Step 3
Surfaced Model of the Wheel

Step 4

Create a block of the model. Name it:

AutoCAD 3D Lab 16-1D. Pick an appropriate location for 0,0,0. Make 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.

Lab Exercise 16-1E OPEN BOOK

Step 1

On layer: Model, draw a wireframe model of the Washer. (Figure Step 1)

Figure Step 1
Dimensioned Multiview Drawing of the Washer

Step 2

On layer: Construction, add any necessary construction objects that may help insert the model into the assembly.

Step 3

On layer: Surface Washer, surface the complete model. Use faces, meshes, regions, or a mixture of them. (Figure Step 3)

Figure Step 3 Surfaced Model of the Washer

Step 4

Create a block of the model. Name it:

AutoCAD 3D Lab 16-1E. Pick an appropriate location for 0,0,0. Make 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.

Lab Exercise 16-1F OPEN BOOK

Step 1

On layer: Model, draw a wireframe model of the Bolt. (Figure Step 1)

Figure Step 1
Dimensioned Multiview Drawing of the Bolt

Step 2

On layer: Construction, add any necessary construction objects that may help to insert the model into the assembly.

Step 3

On layer: Surface Bolt, surface the complete model. Use faces, meshes, regions, or a mixture of them. (Figure Step 3)

Figure Step 3
Surfaced Model of the
Bolt

Step 4

Create a block of the model. Name it:

AutoCAD 3D Lab 16-1F. Pick an appropriate location for 0,0,0. Make 0,0,0 as the insert point for the block. Ensure that the current UCS is located at the World when creating the block.

Lab Exercise 16-1 OPEN BOOK

Step 1

Step 7

With UCS set to World, copy the complete Caster Assembly 10 inches in the X direction. Rotate the copy of the assembly 180 degrees around the X axis. (Figure Step 7)

Figure Step 7

Solid Modeling

A solid model is the best possible computerized representation of a real object. A solid model is one AutoCAD object. It is a much more complete model then a wireframe or a surfaced model. A solid model, unlike a hollow wireframe or surfaced model, is solid. A solid model can be rendered or shaded plus the mass properties can be obtained from it. Displaying the mass properties is taught in Module 25.

In a lot of ways, constructing a solid model is simpler than constructing a surfaced model. It is important to understand that when you construct solid models, you must still use all of the 3D construction techniques that were taught in the first 16 modules.

Solid Primitives

The most basic method of constructing solid models is to create a series of solid primitives and then add them together or subtract them from one another to complete the solid model. Using solid primitives is not the best method of solid modeling but at times they can be a very useful modeling tool. The six primitives are the box, wedge, cylinder, sphere, cone and torus. See Figure 17-1. In this module, you will be constructing solid boxes, wedges, and cylinders.

The next four modules teaches many different commands and techniques used to construct solid models. You can pick and choose how and when to use them to construct each model.

Figure 17-1
Solid Primitives

AutoCAD Command: BOX

The BOX command is used to create a solid box primitive.

Shortcut: none

Modeling Toolbar

Draw Pull-down

Home Ribbon

AutoCAD Command: WEDGE

The WEDGE command is used to create a solid wedge primitive.

Shortcut: none

Modeling Toolbar

Draw Pull-down

Home Ribbon

AutoCAD Command: ISOLINES

The ISOLINES system variable is used set the number of contour lines that a curved surface solid model will be constructed with. The valid settings are from 0 to 2047. After you change the setting with this variable, the drawing must be regenerated to display the revised setting.

Shortcut: none Command: ISOLINES

Enter new value for ISOLINES <8>: 32

Command:

Isolines = 8                                  Isolines = 32

AutoCAD Command:  UNION

The UNION command is used to join two or more solids together to form one solid object.

Shortcut: none

Modify Pull-down

Solid Editing Toolbar

Home Ribbon

AutoCAD Command: SUBTRACT

The SUBTRACT command is used to subtract one or more solids from another solid.

Shortcut: SU

Modify Pull-down

Solid Editing Toolbar

Home Ribbon

AutoCAD Command: CYLINDER

The CYLINDER command is used to create a solid cylinder primitive.

Shortcut: none

Modeling Toolbar

Raw Pull-down

Home Ribbon

WORK ALONG: Creating Solid Models Using Boxes, Wedges and Cylinders

Step 1

Using the NEW command, start a new drawing using template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 17-1. (Figure Step 2A and 2B)

Figure Step 2A
SE Isometric View – Solid Model

Figure Step 2B
Dimensioned Multiview Drawing

Step 3

Set the current view to SE Isometric, the current UCS to World and the current visual style to 2D Wireframe.

Step 4

Set the current layer to Solid 7.

Step 5

Enter the BOX command, as shown below, to draw the solid box. (Figure Step 5).

Command: BOX

Specify first corner or [Center]: 0,0,0 Specify other corner or [Cube/Length]: @6,4

(6 units in the positive X and 4 units in the positive Y.)

Specify height or [2Point] <3.1668>: 1

(1 unit in the positive Z.)

Command:

Figure Step 5

Step 6

Enter the BOX command, as shown below, to add a box to the model. (Figure Step 6A and 6B).

Command: BOX

Specify first corner or [Center]: (end) P1

Specify other corner or [Cube/Length]: @1,4

Specify height or [2Point] <1.0000>: 3

Command:

Figure Step 6A

Figure Step 6B

Step 7

Using on of the orbit commands, orbit the model slightly. Enter the WEDGE command, as shown below, to create a solid wedge primitive as shown in the figure. Using the MOVE command, move the wedge to centre it. Move the wedge by snapping to the midpoint of the wedge to the midpoint on the box. (Figure Step 7A, 7B, and 7C)

Command: WEDGE

Specify first corner or [Center]: (mid)

(See Figure Step 7A)

Specify other corner or [Cube/Length]: @2,1

Specify height or [2Point] <3.0000>: 2

Command:

Figure Step 7A

Figure Step 7B

Figure Step 7C

Step 8

Draw three construction lines on the edges of the box. (Figure Step 8)

Figure Step 8

Step 9

Offset the construction lines to locate the centre of the holes. (Figure Step 9)

Figure Step 9

Step 10

Enter the ISOLINES system variable, as shown below, setting it to 16. Command: ISOLINES

Enter new value for ISOLINES <4>: 16

Command:

Step 11

Enter the CYLINDER command, as shown below, to construct a cylinder for the left hole. After you do that, construct the cylinder on the right side. (Figure Step 11A and 11B)

Command: CYLINDER

Current wire frame density: ISOLINES=16

Specify centre point for base of cylinder or [Elliptical] <0,0,0>: (int) P3

Specify radius for base of cylinder or [Diameter]: D

Specify diameter for base of cylinder: 0.75

Specify height of cylinder or [Center of other end]: -1

(Since the cylinder is constructed 1 unit in the -Z direction -1 is used here.)

Command:

Figure Step 11A

Figure Step 11B

Step 12

Turn layer Construction off and your model should appear as shown in the figure. (Figure Step 12)

Figure Step 12

Step 13

Enter the UNION command, as shown below, to create one solid from the two boxes and the wedge. (Figure Step 13)

Command: UNION

Select objects: 1 found

Select objects: 1 found, 2 total

Select objects: 1 found, 3 total

(Select one solid at a time by picking them.)

Select objects:

Command:

Figure Step 13

Step 14

Your model is now one solid and should appear as shown in the figure. (Figure Step 14)

Figure Step 14

Step 15

Enter the SUBTRACT command, as shown below, to subtract the two cylinders from the model to create the holes. (Figure Step 15A and 15B)

Command: SUBTRACT

Select solids and regions to subtract from ..

Select objects: 1 found

(Select the solid model. See Figure Step 15A)

Select objects:

(Press Enter to change to subtract mode.)

Select solids and regions to subtract .. Select objects: 1 found

Select objects: 1 found, 2 total

(Select each cylinder by picking them one at a time See Figure Step 15B.)

Figure Step 15A

Figure Step 15B

Step 16

Open the Properties window and select the solid model. Ensure it is one AutoCAD object only. (Figure Step 16)

Figure Step 16

Step 17

Set the current visual style to Realistic. (Figure Step 17)

Figure Step 17

Step 18

Save and close the drawing.

MUST KNOW: When two or more solid primitives are used to construct a solid model, the UNION and/or SUBTRACT commands must be used to create one solid object which is one AutoCAD object. When complete, a solid model must be only one object.

Five Solids that Appear as One Solid.                                                                                One Solid Model or One Object in AutoCAD

Five Solids that Appear as One Solid Shaded                                                           The Solid Model Shaded

Key Principles

Lab Exercise 17-1

Time allowed: 40 minutes.

Step 1

On layer Solid 3, draw a solid model of the object. (Figure Step 1A, 1B, and 1C)

Figure Step 1A
Dimensioned Multiview Drawing

Figure Step 1B Completed Solid Model SE Isometric View

Figure Step 1C Completed Solid Model SW Isometric View

Step 2

Set the Isolines to 16.

Step 3

Use the UNION and SUBTRACT commands to create one solid object only.

Step 4

Set the current visual style to Realistic and check the model by orbiting it with the with the 3DFORBIT command.

Step 5

Check to ensure that the solid is one object only. See Step 16 in WORKALONG: Creating Solid Models Using Boxes, Wedges and Cylinders.

Step 6

Save and close the drawing.

Lab Exercise 17-2

Time allowed: 40 minutes.

Step 1

On layer Solid 1, draw a solid model of the object. (Figure Step 1A, 1B, and 1C)

Figure Step 1A
Dimensioned Multiview Drawing

Step 2

Set the Isolines to 20.

Step 3

If necessary, use the UNION and SUBTRACT commands to create one solid object only.

Step 4

Set the current visual style to Realistic and check the model by orbiting it with the with the 3DFORBIT command.

Step 5

Check to ensure that the solid is one object only. See Step 16 in WORKALONG: Creating Solid Models Using Boxes, Wedges and Cylinders.

Figure Step 1B Completed Solid Model SE Isometric View

Figure Step 1C Completed Solid Model SW Isometric View

Step 6

Save and close the drawing.

Constructing Solid Models Without Using Solid Primitives

Constructing most solid models using solid primitives would be to difficult and slow. It is much faster and simpler to construct most solid models using the EXTRUDE and/or the REVOLVE commands.

Extruding

Extruding involves drawing a closed object and, using the EXTRUDE or the PUSHPULL command, project it in the Z direction at a given distance. See Figure 18-1. The closed object can be a 2D polygon, a circle or an ellipse. Extruded solids can then be joined with the UNION command or subtracted using the SUBTRACT command to form the final solid model.

Revolving

Not all solid models can be extruded. A solid model that is symmetrical can be created by revolving a closed object. See Figure 18-2. The closed 2D object can be a polygon, a circle or an ellipse. It is then revolved around an axis. The contour of the object will create the solid as it is revolved around the axis. It can be revolved any angle from 1 degree to 360 degrees.

Figure 18-1
Extruding a Solid Model

Figure 18-2
Revolving a Solid Model

AutoCAD Command: JOIN

The JOIN combines a series of finite linear and open curved objects at their common endpoints to create a single 2D or 3D object.

Shortcut: J

Modify Toolbar

Home Ribbon

Modify Pull-down

AutoCAD Command: EXTRUDE

The EXTRUDE command is used to create a solid by projecting a closed 2D object along the Z axis of the current UCS.

Shortcut: EXT

Modeling Toolbar

Draw Pull-down

Home Ribbon

WORK ALONG: Creating a Extruded Solid Model Using the EXTRUDE Command

Step 1

Using the NEW command, start a new drawing using template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 18-1.

Step 3

Set the current visual style to 2D Wireframe, set the layer: Pline as the current layer, the current view to SE Isometric, and the current UCS to World.

Step 4

Draw the top contour of the wireframe model only. Use the multiview drawing as a reference. (Figure Step 4A and 4B)

Figure Step 4A

Figure Step 4B

Step 5

Set the current UCS to Top and locate it at the centre of the circle as shown in the figure. (Figure Step 5)

Figure Step 5

Step 6

Enter the DELOBJ system variable as shown below. Ensure that it is set to 0. Command: DELOBJ

Enter new value for DELOBJ <1>: 0

Command:

Step 7

Set the system variable ISOLINES to 32, as shown below. Command: ISOLINES

Enter new value for ISOLINES <4>: 32

Command:

Step 8

Enter the JOIN command, as shown below, to create a single 2D polyline from the 8 lines and arcs. (Figure Step 8)

Command: JOIN

Select source object or multiple objects to join at once:

1 found

Select objects to join: 1 found, 2 total

Select objects to join: 1 found, 3 total

Select objects to join: 1 found, 4 total

Select objects to join: 1 found, 5 total

Select objects to join: 1 found, 6 total

Select objects to join: 1 found, 7 total

Select objects to join: 1 found, 8 total

Select objects to join:

8 objects converted to 1 polyline

Command:

Figure Step 8

Step 9

Click the newly created pline and insure it is closed using the Properties window. (Figure Step 9)

Figure Step 9

Step 10

Using what you learned in the last two steps join the inside 4 lines and arcs to create on 2D polyline. Check to ensure it is closed using the Properties window. (Figure Step 10)

Figure Step 10

Step 11

Set layer: Solid 3 as the current layer. Enter the EXTRUDE command, as shown below, to create the solid model.

Command: EXTRUDE

Current wire frame density: ISOLINES=32

Select objects: 6 found

(Select all of the objects in a window or pick then individually.)

Select objects:

Specify height of extrusion or [Path]: -0.75

(Use -0.75 since the extrusion in the negative Z direction.)

Specify angle of taper for extrusion <0>:

(Press Enter to select the default.)

Command:

Step 12

Turn layer: Pline off and your model should appear as shown in the figure. (Figure Step 12)

Figure Step 12

Step 13

Set the current visual style to Realistic. (Figure Step 13)

Figure Step 13

Step 14

Set the current visual style to 2D Wireframe. Enter the SUBTRACT command to subtract the five inner solids from the larger solid. (Figure Step 14)

Figure Step 14

Step 15

Set the current visual style to Realistic. Your model should now appear as shown in the figures. Using the ORBIT command, orbit the model to enure the holes go through the model. (Figure Step 15)

Figure Step 15 SE Isometric View

Step 16

Save and close the drawing.

AutoCAD Command:  PRESSPULL

The PRESSPULL command is used to create a solid by either selecting an area formed by a closed boundary (or boundaries) or a closed 2D object.

Shortcut: none

Modeling Toolbar

Home Ribbon

WORK ALONG:  Creating a Extruded Solid Model Using the PRESSPULL Command

Step 1

Using the NEW command, start a new drawing using template: 3D Layout Metric.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 18-2.

Step 3

Set the current visual style to 3D Wireframe, set layer: Pline, the current view to SE Isometric, and the current UCS to World.

Step 4

Draw the top contour of the wireframe model only. Use the multiview drawing as a reference. (Figure Step 4A and 4B)

Figure Step 4A

Figure Step 4B

Step 5

Use the JOIN command to create a single 2D polyline. Use the Properties window to ensure that the polyline is closed.

Step 6

Set layer: Solid 2 as the current layer.

Step 7

Enter the DELOBJ system variable as shown below and ensure that it is set to 0.

Command: DELOBJ

Enter new value for DELOBJ <1>: 0

Command:

Step 8

Enter the PRESSPULL command. When prompted, select the polyline. Move the cursor in the positive Z direction and the solid will extrude with it. Enter 30 for the height. (Figure Step 8A and 8B)

Command: PRESSPULL

Select object or bounded area:

Specify extrusion height or [Multiple]:

Specify extrusion height or [Multiple]: 30

1 extrusion(s) created

Select object or bounded area:

Command:

Figure Step 8A

Figure Step 8B

Step 9

Using the multiview drawing for the dimensions, draw the lines and arcs in the Front and Right Side of the model. Use the JOIN command to join the plines and ensure that they are closed. (Figure Step 9)

Figure Step 9

Step 10

Enter the PRESSPULL command and when prompted, select inside the closed pline as shown in the figure. Snap to the back corner to indicate the depth of the extrusion. (Figure Step 10A and 10B)

Figure Step 10A

Figure Step 10B

Step 11

Using the same principle as Step 10, use the PRESSPULL command to extrude the other pline. (Figure Step 11A, 11B, and 11C)

Figure Step 11A

Figure Step 11B

Figure Step 11C

Step 12

Turn layer: Pline off.

Step 13

Your completed model should appear as shown on the figure. (Figure Step 13)

Figure Step 13

Step 14

Save and close the drawing

AutoCAD Command:  REVOLVE

The REVOLVE command is used to create a solid model by revolving a 2D object around an axis.

Shortcut: REV

Modeling Toolbar

Draw Pull-down

Home Ribbon

WORK ALONG:  Creating a Revolved Solid Model

Step 1

Using the NEW command, start a new drawing using template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 18-3. (Figure Step 2)

Figure Step 2
Dimensioned Multiview Drawing

Step 3

Set layer Pline as the current layer and current visual style to 2D Wireframe.

Step 4

Set the current view to SE Isometric and the current UCS to Right. (Figure Step 4)

Figure Step 4

Step 5

Using the multiview drawing as a reference, draw one-half of the right side cross section of the solid part of the object. (Figure Step 5)

Figure Step 5

Step 6

On layer: Construction, from 0,0,0 draw a line, of any length, along the X axis. Use ortho mode to draw it quicker. This will be the axis for the revolution and is the centre line of the solid. (Figure Step 6)

Figure Step 6

Step 7

Using the JOIN command, create a closed polygon from the lines. Ensure that it is closed. (Figure Step 7)

Figure Step 7

Step 8

Set the ISOLINES system variable to 48 as shown below. Command: ISOLINES

Enter new value for ISOLINES <4>: 48

Command:

Step 9

Set layer Solid 3 as the current layer. Enter the REVOLVE command, as shown below. After completing the command, the model should appear as shown in the figure. (Figure Step 9)

Command: REVOLVE

Current wire frame density: ISOLINES=48

Select objects: 1 found

(Select the closed polyline.)

Select objects:

(Press Enter.)

Specify start point for axis of revolution or define axis by

[Object/X (axis)/Y (axis)]: O

Select an object:

(Select the axis (the construction line.)

Specify angle of revolution <360>:

(Press Enter to select the default.)

Command:

Figure Step 9

Step 10

Turn off layers: Construction and Pline and set the current visual style to Realistic. (Figure Step 10)

Figure Step 10
SE Isometric View

Step 11

Using 3D Orbit, orbit the model as shown in the figure. (Figure Step 11).

Figure Step 11

Step 12

Save and close the drawing.

Key Principles

Lab Exercise 18-1

Time allowed: 45 minutes.

Step 1

Set the system variable DELOBJ to 0.

Step 2

Draw the closed plines on layer: Pline.

Step 3

On layer: Solid 1, draw a solid model of the object. (Figure Step 3A and 3B)

Figure Step 3A Dimensioned Wireframe SE Isometric View

Figure Step 3B
Solid Model SE Isometric View

Step 4

Use the UNION and SUBTRACT commands to complete the solid model. When complete, the solid must be one object.

Step 5

Turn layers: Construction and Pline off and set the current visual style to Realistic.

Step 6

Set the Insertion Units, change the current UCS to World and check the model with the key.

Step 7

Save and close the drawing.

Lab Exercise 18-2

Time allowed: 45 minutes.

Step 1

Set the system variable DELOBJ to 0.

Step 2

On layer: Solid 3, draw a solid model of the object. (Figure Step 2A, 2B, 2C, and 2D)

Figure Step 2A Dimensioned Wireframe SE Isometric View

Figure Step 2B
View of Keyway – Rotated

Figure Step 2C
Key Detail

Figure Step 2D
Solid Model SE Isometric View

Step 3

On layer: Pline, draw the closed plines.

Step 4

Use the UNION and SUBTRACT commands to complete the solid model. When complete, the solid must be one object.

Step 5

Turn layers: Construction and Pline off and set the current visual style to Realistic.

Step 6

Set the Insertion Units, change the current UCS to World, and check the model with the key.

Step 7

Save and close the drawing.

Lab Exercise 18-3

Time allowed: 60 minutes.

Step 1

Set the system variable DELOBJ to 0.

Step 2

On layer: Solid 4, draw a solid model of the object. (Figure Step 2A, 2B, and 2C)

Figure Step 2A
Dimensioned Multiview Drawing

Figure Step 2B Completed Solid Model SE Isometric View

Figure Step 2C Completed Solid Model NE Isometric View

Step 3

On layer: Pline, draw the closed plines.

Step 4

Use the UNION command to complete the solid model. When complete, the solid must be one object.

Step 5

Turn layers: Construction and Pline off and set the current visual style to Realistic.

Step 6

Set the Insertion Units, change the current UCS to World, and check the model with the key.

Step 7

Save and close the drawing.

Hint 1

See steps below:

Lab Exercise 18-4

Time allowed: 45 minutes.

Step 1

Set the system variable DELOBJ to 0.

Step 2

On layer: Solid 5, draw a solid model of the object. (Figure Step 2A, 2B, and 2C)

Figure Step 2A
Dimensioned Multiview Drawing

Figure Step 2B Completed Solid Model SE Isometric View

Figure Step 2C Completed Solid Model NE Isometric View

Step 3

On layer: Pline, draw the closed pline.

Step 4

When complete, the solid model must be one object.

Step 5

Turn layers: Construction and Pline off and set the current visual style to Realistic.

Step 6

Set the Insertion Units, change the current UCS to World, and check the model with the key.

Step 7

Save and close the drawing.

Lab Exercise 18-5

Time allowed: 45 minutes.

Step 1

Set the system variable DELOBJ to 0.

Step 2

On layer: Solid 3, draw a solid model of the object. (Figure Step 2A, 2B, and 2C)

Figure Step 2A
Dimensioned Wireframe Model

Figure Step 2B
Completed Solid Model SE Isometric View

Figure Step 2C
Completed Solid Model NW Isometric View

Step 3

On layer: Pline, draw the closed plines.

Step 4

Use the UNION and SUBTRACT commands to complete the solid model. When complete, the solid must be one object.

Step 5

Turn layers: Construction and Pline off and set the current visual style to Realistic.

Step 6

Set the Insertion Units, change the current UCS to World, and check the model with the key.

Step 7

Save and close the drawing.

Working With Composite Solids

When you are constructing solid models, it is important to ensure that the completed solid model consists of only one object. The three commands used to help you to do this are UNION, SUBTRACT and INTERSECT. Study the following figures to help you understand how these commands affect the solid model.

Figure 19-1 shows two solid models in which parts of each one occupies the same 3D space. This, of course, would be impossible in real life.

Figure 19-1
Two Solids

Figure 19-2 shows the same model after the UNION command was used to join the two solids into one.

Figure 19-2
One Solid

Figure 19-3 shows a shaded model and how the model in Figure 19-1 will appear when the two solids are joined together with the UNION command.

Figure 19-3
One Solid – Joined With UNION Command

Figure 19-4 shows how the two solids in Figure 19-1 will appear when the cylinder is subtracted from the box using the SUBTRACT command.

Figure 19-4
One Solid – Subtracted

Figure 19-5 shows how the two models in Figure 19-1 would appear when the box is subtracted from the cylinder using the SUBTRACT command.

Figure 19-5
One Solid
Subtracted

Figure 19-6 shows how the solid models in Figure 19-1 would appear if the INTERSECT command is used. Notice how only the volume shared by the two models remains.

Figure 19-6
One Solid
Intersection

AutoCAD Command: INTERSECT

The INTERSECT command is used to create a solid by finding the volume shared by two or more solids.

Shortcut: none

Solid Editing Toolbar

Modify Pull-down

Home Ribbon

WORK ALONG: Creating a Solid Model by Intersecting Two or Three Solid Models

Step 1

Using the NEW command, start a new drawing using template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 19-1.

Step 3

Ensure that the DELOBJ system variable is set to 0.

Step 4

Set layer: Pline as the current layer, the current UCS to Front, the current view to SE Isometric, and the current visual style to 2D Wireframe.

Step 5

Set the current UCS to Front. Using the figures as a reference, draw the contour of the Front view. (Figure Step 5A and 5B)

Figure Step 5A
Dimensioned Wireframe Model

Figure Step 5B

Step 6

Using the JOIN command, create a closed polyline. (Figure Step 6)

Figure Step 6

Step 7

Set the current UCS to Right and relocate the UCS to the right side as shown in the figure. Using the PLINE command, draw a closed pline of the contour of the right side. (Figure Step 7)

Figure Step 7

Step 8

Set the current UCS to Top and relocate it to the top corner of the model as shown in the figure. Using the PLINE command, draw a closed pline of the contour of the top view. (Figure Step 8)

Figure Step 8

Step 9

Set layer: Solid 3 as the current layer. Extrude the Front view the depth of the model. (Figure Step 9)

Figure Step 9

Step 10

Set the current visual style to Realistic to see the extruded solid. (Figure Step 10)

Figure Step 10

Step 11

Set the current visual style to 2D Wireframe. Using PRESSPULL, extrude the Right Side and the Top view. Set the current visual style to Realistic to see all three extruded solids at the same time. (Figure Step 11A and 11B)

Figure Step 11A

Figure Step 11B

Step 12

Save drawing.

Step 13

Set the current visual style to 2D Wireframe. Enter the INTERSECT command, as shown below, to create the common solid from the three intersecting solids. (Figure Step 13)

Command: INTERSECT

Select objects: 1 found

Select objects: 1 found, 2 total

Select objects: 1 found, 3 total

(Select each of the solid models.)

Select objects:

Command:

Figure Step 13

Step 14

Set the current visual style to Realistic. (Figure Step 14)

Figure Step 14

Step 15

Save and close the drawing.

AutoCAD Command: FILLETEDGE

The FILLETEDGE command is used to create a fillet (tangent arc) on the edge or edges of a solid model.

Shortcut: none

Modify Pull-Down

Solid Editing Toolbar

Solid Ribbon

AutoCAD Command: CHAMFEREDGE

The CHAMFEREDGE command is used to create a chamfer on the edge or edges of a solid model.

Shortcut:  none

Modify Pull-down

Solid Editing Toolbar

Solid Ribbon

WORK ALONG: Creating Fillets and Chamfers on Solid Models

Step 1

Using the NEW command, start a new drawing using template: 3D Layout English.

Step 2

Save and name the drawing: AutoCAD 3D Workalong 19-2.

Step 3

Set layer: Pline as the current layer, the current UCS to Front, the current view to SE Isometric, and the current visual style to 2D Wireframe. Create a the closed pline on the Front view using the figures as a reference. Ignore the fillets and rounds. (Figure Step 3A, 3B, and 3C)

Figure Step 3A
Dimensioned Multiview of Model 1

Figure Step 3B Completed Solid Model of Model 1 –
SE Isometric View

Figure Step 3C
Location of 0,0,0

Step 4

On layer: Solid 2, create a solid model as shown in the figure. Do not include the fillets and rounds. For the hole, extrude a circle. Check to ensure that your model is one solid object only using the Properties window. (Figure Step 4A and 4B)

Figure Step 4A

Figure Step 4B

Step 5

Turn layer: Pline off.

Step 6

Set the current UCS to Top. Copy the solid model, that you completed in Step 4, 8 inches in the positive Y direction. The 8 inches is measured from the same point on model to the same point on the copy. The actual distance between the two model will be 5 inches. (Figure Step 6)

Figure Step 6

Apply Steps 7 to 10 to the model on the left side of Figure Step 6.

Step 7

Turn layer: Pline off. Enter the FILLETEDGE command, as shown below, to fillet the bottom corners. (Figure Step 7)

Command: FILLETEDGE

Radius = 1.2500

Select an edge or [Chain/Loop/Radius]: P1

Select an edge or [Chain/Loop/Radius]: P2

Select an edge or [Chain/Loop/Radius]:

2 edge(s) selected for fillet.

Press Enter to accept the fillet or [Radius]: R

Specify Radius or [Expression] <1.0000>: 1

Press Enter to accept the fillet or [Radius]:

Command:

Figure Step 7

Step 8

Enter the FILLETEDGE command, as shown below, to fillet the top edge. (Figure Step 8)

Command: FILLETEDGE

Radius = 1.0000

Select an edge or [Chain/Loop/Radius]: P3

select an edge or [Chain/Loop/Radius]: C

(Use the Chain option.)

Select an edge chain or [Edge/Radius]: E

Select an edge or [Chain/Loop/Radius]: P4

Select an edge or [Chain/Loop/Radius]: P5