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Tools for Design: Engineering Graphics Principles and

AutoCAD 2007

Nighat Yasmin Clemson University

SDC

Schroff Development Corporation

www.schroff.com

www.schroff-europe.com

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Basics of Solid Modeling 203

8. Basics of Solid Modeling

8.1. Objectives After completing this chapter, students should know

• How to create basic three dimensional objects

• How it add and subtract 3D solid

• How to combine basic objects to create complicated model.


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204 Tools for Design: Engineering Graphics Principles and AutoCAD 2007

8.2. Introduction This chapter will discuss the capabilities of the Dashboard (Figure 8-1a) and the Solid Editing toolbar (Figure 8-1b).

Figure 8-1a

Figure 8-1b

Figure 8-1b

8.3. 3D solid modeling AutoCAD supports three types of 3D models: wireframe, surface, and solid. Each type has its own creation and editing techniques.

• Wireframe model: A wireframe model is a skeletal description of a 3D object, Figures 8-2a and b. There are no surfaces in a wireframe model; it consists only of points, lines, and curves that describe the edges of the object. Because each object that makes up a wireframe model must be independently drawn and positioned, this type of modeling can be the most time-consuming.

• Surface model: A surface model is more sophisticated than a wireframe model, in that it defines not only the edges of a 3D object, but also its surfaces.

• Solid model: A solid model is the easiest type of 3D modeling to use and create Figure 8-2c. Complicated models can be created by

Union Subtraction

Intersection

Extrude


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o creating basic 3D shapes: boxes, cones, cylinders, spheres, wedges, and torus;

o combining basic shapes to create solids that are more complex by joining, subtracting, and/or finding their overlapping volume;

o sweeping a 2D object along a path or revolving it about an axis; and/or o defining the shape using a polyline and extruding it into a solid.

Figure 8-2a Figure 8-2b Figure 8-2c

8.4. Isolines In AutoCAD, isolines represent the wire frame density. It specifies the number of contour lines per surface on an object. The default value for the number of isolines is 4. However, the user can specify any number from 0 to 2047. Figure 8-2a and Figure 8-2b represents a sphere with 4 and 20 isolines, respectively.

• To change the number of isolines, (i) type Isolines on the command line, (ii) press the Enter key, (iii) specify the new value, and (iv) press the Enter key to complete the process.

8.5. Length, width, and height In AutoCAD, the length corresponds to the dimension along the X-axis, the width to the Y-axis, and the height to the Z-axis as shown in Figure 8-3. Entering a positive value for a length will draw the length along the positive X-axis of the current UCS and entering a negative value draws the length along the negative X-axis. The same is true for the width and height dimensions.

Figure 8-3


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8.6. Visual style The display of a 3D object depends on many factors, such as color, light, shadow, number of isolines, edges, etc. To make the process of object creation faster, AutoCAD provides 5 different visual styles. A visual style is a collection of settings to control the display.

• 2D wireframe: This option is used to displays the objects using lines and curves to represent the boundaries.

• 3D wireframe: This option is used to displays the objects using lines and curves to represent the boundaries, Figure 8-4a.

• 3D hidden: This option is used to displays the objects using the 3D wireframe representation and hides lines representing the back faces, Figure 8-4b.

• Realistic: This option is used to shade the objects and smooth the edges between polygon faces, Figure 8-4c.

• Conceptual: This option shades the objects and smoothes the edges between polygon faces, Figure 8-4d.

Figure 8-4a Figure 8-4b

Figure 8-4c Figure 8-4d

• The visual style can be changed using one of the following procedures. 15. Toolbar method: Click on the desired tool on the Visual Styles toolbar, Figure

8-5a. 16. Menu method: Select the Tools dropdown menu and then select Palettes �

Dashboard � Visual Styles control panel and click on the desired option, Figure 8-5b.

17. Command line method: (i) Type “vscurrent”, “Vscurrent”, or “VSCURRENT” on the command line. (ii) Press the Enter key. (iii) Type 2, 3, h, r, or c. (iv) Finally, press the Enter key.


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8.7. File setup for 3D modeling A 3D object can be created in a 2D or 3D drawing file. The default settings of the two files are different; but the toolbars can be added as needed. The basic commands discussion will list the toolbar needed.

8.7.1. 3D object in 2D file • Open a new acad (or acadiso) file.

• Activate the View command and select SE Isometric view.

• Add the desired toolbars.

• Create the 3D object.

8.7.2. 3D object in 3D file • Open a new acad (or acadiso) file.

• Turn off the perspective projection option.

• Add the desired toolbars.

• Create the 3D object.

8.7.3. Perspective and parallel projection The 3D files provide the option of perspective or parallel projection. By default, a 3D file is in perspective projection mode. A perspective projection requires a distance between a theoretical camera and a target point. Architectural drawings generally use perspective projection; and mechanical drawings are created using parallel projection. To turn off the perspective view (the view will change to the parallel view), (i) type Perspective on the command line and press the Enter key, (ii) type 0 and press the Enter key. 0 means that the perspective view is off and 1 means that the perspective view is on.

2D wireframe

3D hidden

3D wireframe

Realistic

Conceptual

Wireframe

2D 3D

3D

hidden

Conceptual

Realistic


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8.8. Box The Box command is used to draw a 3D solid box with the base of the box parallel to the XY plane of the current UCS.

• Example: Create a rectangular box based on the corner of the box at the origin, Length = 20 inches, Width = 15 inches, and Height = 2.5 inches.

• Open a new acad3D template file (or the corresponding template created in Chapter #6).

• Turn off the perspective view.

• The Box command is activated using one of the following procedures. 4. Menu methods:

a. Select Draw dropdown menu � Modeling � Box. b. Select the Tools dropdown menu and then select Palettes � Dashboard

� Visual Styles control panel � Box. 5. Command line method: Type “box”, “Box”, or “BOX” in the command line

and press the Enter key.

• The activation of the command will result in the prompt shown in Figure 8-6a. Use the down arrow key to display the various options.

Figure 8-6a

• First corner or center: In AutoCAD, a box drawing is started by specifying either a corner (default option) or the center of the box, Figure 8-6a.

• Press the down arrow key to close the Center option. Specify the coordinates of the corner at the origin, (i) type 0 for the X value and press the comma key, (ii) type 0 for the Y value and press the comma key, and (iii) type 0 for the Z value and press the Enter key.

• The prompt shown in Figure 8-6b will appear. Use the down arrow key to display the various options.

• Cube or length option: Allows to draw a cubical (all sides of equal length) box or rectangular box. If a user selects the Cube option followed by pressing the Enter key, then the software requires only the Length dimension. On the other hand, if a user selects Length option, then the software requires the Length, Width, and Height to create a rectangular box.

• Select the Length option (Figure 8-6b) and press the Enter key. (The Wedge command shows the use of the Cube option).


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Figure 8-6b

• The prompt shown in Figure 8-6c will appear.

• Turn on the ORTHO command by clicking the corresponding button on the status bar.

• Enter the length (20) and press the Enter key.

• Enter the width (15) and press the Enter key.

• Enter the height (2.5) and press the Enter key.

• Figure 8-6d shows the box just created. The box is shown using the Conceptual style.


8.9. Wedge The Wedge command is used to draw a 3D solid wedge shaped object with a sloped face tapering along the X axis.

• Example: Create a cubical wedge based on the corner of the box at (2, 3, 4) and Length = 10 mm.

• Open a new acad3Diso template file (or the corresponding template created in Chapter #6).

• Turn off the perspective view.

• The Wedge command is activated using one of the following procedures. 1. Menu methods:

a. Select the Draw dropdown menu � Modeling � Wedge. b. Select the Tools dropdown menu and then select Palettes � Dashboard

� Visual Styles control panel � Wedge. 2. Command line method: Type “wedge”, “Wedge”, or “WEDGE” in the

command line and press the Enter key.


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• The activation of the command will result in the prompt shown in Figure 8-7a. Use the down arrow key to display the various options. Choose the first corner option, and specify the coordinates of the first corner, Figure 8-7a. Use the comma key to move the cursor to the next field, and press the Enter key after specify the Z value.

Figure 8-7a

• Cube or length option: The prompt to select the Cube or Length option will appear. Select the Cube option, Figure 8-7b. (The Box command shows the use of the Length option).

.

Figure 8-7b Figure 8-7c

• The prompt to specify the length will appear.

• Turn on the ORTHO command.

• Specify the length (10) and press the Enter key.

• Figure 8-7c shows the wedge just created. The wedge is shown using Realistic

style.

8.10. Cone The Cone command is used to draw a 3D solid cone. The cone is created by specifying the bottom and top radii and the height of a cone, Figure 8-8a. The base of the cone can be a cylinder or elliptical. This command can be used to draw a cone with the pointed top by specifying the top radius equal to zero; cylinder by specifying the top radius equal to the base radius; and cone frustum by specifying the top radius neither zero nor equal to the base radius. In Figure 8-8b, TR represents top radius and BR represents the base radius.


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Figure 8-8a

Figure 8-8b

• Example: Create a cone frustum at the origin with a base diameter of 2 inches, top diameter of 1 inch, and height of 3.5 inches.

• Open a new acad template file (or the corresponding template created in Chapter #6).

• Select the SE Isometric view from the View toolbar or View dropdown menu � 3D Views � SE Isometric option.

• The Cone command is activated using one of the following procedures. 1. Menu methods:

(i) Select the Draw dropdown menu � Modeling � Cone. (ii) Select the Tools dropdown menu and then select Palettes � Dashboard

� Visual Styles control panel � Cone. 2. Command line method: Type “cone”, “Cone”, or “CONE” in the command

line and press the Enter key.

• The activation of the command will result in the prompt shown in Figure 8-9a. Use the down arrow key to display the various options. The base of a cone can be circular or elliptical. The base of a cone is drawn as a circle or an ellipse as discussed in the Chapter #3.

• In this example, a circular based cone with the specification of the base center is created. The center of the cone is at the origin.

TR = 0 BR = 2*TR BR = TR


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Figure 8-9a


Figure 8-9b

• Specify the base radius (2) and press the Enter key. The prompt to specify the height will appear, Figure 8-9c. Use the down arrow key to display the various options. Select the Top radius option and press the Enter key.


• Specify the base radius (1.5) and press the Enter key.

• Specify the height (3.5) and press the Enter key.

• Figure 8-9d shows the cone just created. The cone is shown using the 3D

Wireframe style.


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8.11. Sphere The Sphere command is used to draw a 3D solid sphere.

• Example: Create a sphere of 50mm diameter.

• Open a new acadiso template file (or the corresponding template created in Chapter #6).


• The Sphere command is activated using one of the following procedures. 1. Menu methods:

(i) Select the Draw dropdown menu � Modeling � Sphere. (ii) Select the Tools dropdown menu and then select Palettes � Dashboard

� Visual Styles control panel � Sphere. 2. Command line method: Type “sphere”, “Sphere”, or “SPHERE” in the



Figure 8-10a

• The circumference of a sphere is drawn as a circle discussed in the Chapter #3.

• Click at the desired location for the center of the sphere, and the prompt shown in Figure 8-10b will appear. Use the down arrow key to display the various options.

Figure 8-10b

• Select the Diameter option (Figure 8-10b) and press the Enter key.

• Enter the diameter (50) and press the Enter key.

• Figure 8-10c shows the sphere just created. Increase the number of isolines to 20, the resulting sphere is shown in Figure 8-10d.


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8.12. Cylinder The Cylinder command is used to draw a 3D solid cylinder with the base of the cylinder parallel to the XY plane of the current UCS.

• Example: Create a 20 mm high cylinder with the base radius of 40mm.



• The Cylinder command is activated using one of the following procedures. 1. Menu methods:

(i) Select the Draw dropdown menu � Modeling � Cylinder. (ii) Select the Tools dropdown menu and then select Palettes � Dashboard

� Visual Styles control panel � Cylinder. 2. Command line method: Type “cylinder”, “Cylinder”, or “CYLINDER” in the


• The activation of the command will result in the prompt shown in Figure 8-11a. Use the down arrow key to display the various options. The base of a cylinder can be circular or elliptical. The base of a cylinder is drawn as a circle or an ellipse as discussed in the Chapter #3.

Figure 8-11a

• Choose the desired option, and draw the base. This example uses the origin as the center point.



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Figure 8-11b

• Specify the base radius (40) and press the Enter key.

• Specify the height (20) and press the Enter key.

• Figure 8-11c shows the cylinder just created (isolines were set to 20). The cylinder is shown using the 2D Wireframe style.

Figure 8-11c

8.13. Pyramid The Pyramid command is used to draw a 3D solid pyramid with a 3- to 32-sided base. This command can be used to draw a pyramid with a pointed top by specifying the top radius equal to zero; box by specifying the top radius equal to the base radius; and a pyramid frustum by specifying the top radius neither zero nor equal to the base radius.

• Example: Create a 10 sided pyramid with the center of the base at the origin, a base diameter equal to 40 mm, and a height equal to 50 mm.



• The Pyramid command is activated using one of the following procedures. 1. Menu methods:

(i) Select the Draw dropdown menu � Modeling � Pyramid. (ii) Select the Tools dropdown menu and then select Palettes � Dashboard

� Visual Styles control panel � Pyramid. 2. Command line method: Type “pyramid”, “Pyramid”, or “PYRAMID” in the

command line, and press the Enter key.


1. Edge option: A pyramid will be drawn with the specification of the end points of an edge. The number of edges will be equal to the number of edges in the previously created pyramid.


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2. Sides option: A pyramid will be drawn with the specification of the number of sides.

Figure 8-12a

• Select the Sides option (Figure 8-12a) and press the Enter key. The prompt to specify the number of sides will appear, Figure 8-12b.

• Type in the number of sides (10), Figure 8-12b, and press the Enter key. The prompt to specify the center point of the base will appear, Figure 8-12b. Type 0,0,0 for the center and press the Enter key.

Figure 8-12b

• The command to specify the base radius will appear, Figure 8-12c. Press the down arrow key to visualize the options. The base polygon can be drawn outside (circumscribed) or inside (inscribed) a circle of the base radius. However, if the previous pyramid was drawn with the inscribed option then only the circumscribed option will be available and vice versa.

Figure 8-12c

• (i) Select the Circumscribed option (Figure 8-12c) and press the left button of the mouse. (ii) Specify the base radius (20) and press the Enter key.

• Specify the height (50), Figure 8-12d, and press the Enter key.

• Figure 8-12e shows the pyramid just created. The pyramid is shown using the Conceptual style.


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Figure 8-12d Figure 8-12e

8.14. Torus The Torus command is used to draw a 3D solid ring by specifying the radius (or diameter) of the torus and the radius (or diameter) of the tube, Figure 8-13. The radius of the torus is the distance from the center of the torus to the center of the tube.

• The Torus command is activated using one of the following procedures. 1. Menu methods:

(i) Select the Draw dropdown menu � Modeling � Torus. (ii) Select the Tools dropdown menu and then select Palettes � Dashboard

� Visual Styles control panel � Torus. 2. Command line method: Type “torus”, “Torus”, or “TORUS” in the command

line and press the Enter key.

• The activation of the command will result in the prompt to specify the center.

Figure 8-13

• Specify the center of the torus and press the Enter key.

• Specify the radius (or diameter) of the torus and press the Enter key.

• Specify the tube’s radius (or diameter) and press the Enter key.


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• Figure 8-13 shows the torus just created. The torus is shown using the Realistic style. The number of isolines is 4.

8.15. Extrude The Extrude command is used to create a unique 3D solid by extruding an existing 2D object; the object is extruded along the Z axis of the current UCS, Figure 8-14a. Polylines, polygons, circles, ellipses, and closed splines can be extruded. However objects contained within a block or polylines that have crossing or self-intersecting segments cannot be extruded. To extrude a polyline, it must contain at least 3 but not more than 500 vertices. If a closed or an open object is extruded then the resulting object is a solid or a surface, respectively.

Figure 8-14

• Example: To follow the extrude command, draw a hexagon of arbitrary dimensions which is centered at the origin.


• Select SE Isometric view from the View toolbar or View dropdown menu � 3D

Views � SE Isometric option.

• Draw the hexagon.

• The Extrude command is activated using one of the following procedures. 1. Toolbar methods:

(i) Toolbar method: Select the Extrude tool from the Solid Editing toolbar. 2. Menu methods:

(i) Select the Draw dropdown menu � Modeling � Extrude. (ii) Select the Tools dropdown menu and then select Palettes � Dashboard

� Visual Styles control panel � Extrude. 3. Command line method: Type “extrude”, “Extrude”, or “EXTRUDE” in the


• The activation of the command will result in the prompt shown in Figure 8-15a.

• Select the object: (i) Bring the cursor on the object to be extruded. (ii) Press the left button of the mouse. (iii) Press the Enter key. This will show the prompt shown in Figure 8-15b.

• Use the down arrow key to display the various options, Figure 8-15a. 1. Height of extrusion: A positive value would extrude the objects along the

positive Z axis and a negative value would extrude the objects along the negative Z axis.


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2. Taper Angle: Specify angle (between –90 and +90 degrees) of taper for extrusion. A positive angle tapers the object in from the base object and negative angles taper out. The default angle (0 degree) extrudes a 2D object perpendicular to its 2D plane, Figures 8-15d, e, and f.


• Select the Taper Angle options (Figure 8-15b) and press the left button of the mouse. Press the Enter key. The prompt to specify the taper angle will appear, Figure 8-15c.

Figure 8-15c

• Type the angle (10) and press the Enter key.

• The prompt to specify the height of extrusion will appear. Type the height (10) and press the Enter key.

• Figure 8-15d shows the extruded hexagon just created. The extruded hexagon is shown using 3D Hidden style. Create the extruded hexagon shown in Figures 8-15e and f. In the figures, TA represents the taper angle and H represents the height of the extrusion.

Figure 8-15d Figure 8-15e Figure 8-15f

TA = -10o

H = 15

TA = 10o

H = 15

TA = 0o

H = 15


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8.16. Example #1 Create the shape shown in Figures 8-16d or e.

• Open a new acad3Diso template file (or the corresponding template created in Chapter #6).

• Turn off the perspective option.

• Draw a cubical box, with the first corner at the origin (0,0,0) and length of 200mm, Figure 8-16a.

• Select the Origin option from the UCS toolbar; and set the origin of the UCS at (-100, 100,100), Figure 8-16b.

• Select Y option from the UCS toolbar to rotate the UCS about y-axis and set the angle of rotation to 90 degree, Figure 8-16c.


• Draw a cone, with the center point of the base at the origin (0,0,0), a base radius of 150mm, and a height of 700. Figure 8-16d show the objects using the 3D

Hidden style and Figure 8-16e shows the objects using the Conceptual style


8.17. Union The Union command is used to create a unique 3D solid by combining selected solids by addition. The command uses the objects created in Example #1.

• The Union command is activated using one of the following procedures. 1. Toolbar method: Select the Union tool from the Solid Editing toolbar. 2. Menu methods: Select the Tools dropdown menu and then select Palettes �

Dashboard � Visual Styles control panel � Union.


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3. Command line method: Type “union”, “Union”, or “UNION” in the command line and press the Enter key.

• The activation of the command will result in the prompt to select the object.

• Select both objects and press the Enter key. The Union command is independent of the order of the object selection.

• Figure 8-17 shows the union of the two objects.

Figure 8-17 Figure 8-18

8.18. Intersection The Intersection command is used to create a unique 3D solid from the intersection of two or more solids and by removing the areas outside of the intersection. The command uses the objects created in Example #1.

• The Intersection command is activated using one of the following procedures. 1. Toolbar methods: Select the Intersection tool from the Solid Editing toolbar. 2. Menu methods: Select the Tools dropdown menu and then select Palettes �

Dashboard � Visual Styles control panel � Intersection. 3. Command line method: Type “intersection”, “Intersection”, or

“INTERSECTION” in the command line and press the Enter key.


• Select both objects and press the Enter key. The Intersection command is independent of the order of the object selection.

• Figure 8-18 shows the new solid created as a result of the intersection of the two objects.

8.19. Subtract The Subtract command is used to create a unique 3D solid by subtraction. The command uses the objects created in Example #1. The Subtract command depends on the order of the object selection, recall that ( ) ( )A B B A− ≠ − .

• The Subtract command is activated using one of the following procedures. 1. Toolbar method: Select the Subtract tool from the Solid Editing toolbar. 2. Menu methods: Select the Tools dropdown menu and then select Palettes �

Dashboard � Visual Styles control panel � Subtract.


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3. Command line method: Type “subtract”, “Subtract”, or “SUBTRACT” in the command line and press the Enter key.


• Select the first object and press the Enter key.

• Select the second object and press the Enter key.

• Figure 8-19a shows the box subtracted from the cone (that is, select the cone as the first object and box as the second object).

• Figure 8-19b shows the cone subtracted from the box (that is, select the box as the first object and cone as the second object).


8.20. Interference The Interference command is used to create a unique 3D solid by the part which is common to all of the objects. The command uses the objects created in Example #1. The Interference command is independent of the order of the object selection.

• The Interference command is activated using one of the following procedures. 1. Menu methods: Select the Modify dropdown menu and then select 3D

Operation � Interference Checking. 2. Command line method: Type “interfere”, “Interfere”, or “INTERFERE” in the


• The activation of the command will result in the prompt to select the first object.

• Select the first object and press the Enter key.

• Select the second object and press the Enter key.

• This will open the Interference Checking dialog box, Figure 8-20.

• Do not check the Delete interference objects created on Close box.

• The user can use the Zoom and Pan buttons, if necessary; this will close the dialog box temporarily; perform the operation and press the Enter key; this will reopen the dialog box.

• Press the Close button to close the dialog box.

• A new solid (the part which is common to both objects) is created, Figure 8-20.

• Select one of the grips point, and move the object to the new location, Figure 8-20b.

• The original objects remain unaffected, Figure 8-20c.


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• The new solids created by the Interference and Intersection commands are the same. The major difference of the two commands is that the Interference command retains the original objects but the Intersection command discards the original objects.

Figure 8-20


8.21. Grips and solid The Grips points in 3D solids can be used in a manner similar to 2D objects. That is, these points can be used stretch, shrink, move, mirror, rotate, and scale the objects. Some of the grips are like arrow heads (Figure 8-22) to show the direction in which they stretch/shrink the figure. The square points can also be used for this purpose, too.

Figure 8-22


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8.22. Create complicated solid model

8.22.1. Example #2 Create the motor shown in Figures 8-23.

Figure 8-23

• The user does not show dimensions on a 3D object.


• Select the SE Isometric view from the View toolbar or View dropdown menu � 3D Views � SE Isometric option, Figure 8-24a.

• Set the visual style to the 3D Hidden style.

• Select the Z option from the UCS toolbar to rotate the UCS about the z-axis and set the angle of rotation to 90 degree, Figure 8-24b.

• Select the X option from the UCS toolbar to rotate the UCS about the x-axis and set the angle of rotation to 90 degree, Figure 8-24c.


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• Draw a polyline of the dimensions shown in Figure 8-24d.

• Create a fillet as shown in Figure 8-24e.


• Mirror the polyline as shown in Figure 8-24f.

• Join the two polylines: (i) Bring the cursor on one of the polyline and press the left button of the mouse. (ii) Press the right button of the mouse, an option panel will appear, Figure 8-24g. (iii) Bring the cursor on the Polyline Edit option, Figure 8-24g, and press the left button of the mouse. (iv) The option panel shown in Figure 8-24h will appear. (v) Select the Join option with left mouse button. (vi) Press the Esc key to exit the command.

Figure 8-24f


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Figure 8-24g Figure 8-24h

• Use the Extrude command to create the solid as shown in Figure 8-24i.

Figure 8-24i

• Select the Origin option from the UCS toolbar; and set the origin of the UCS at (0, 1,-1.5).

• Select the X option from the UCS toolbar to rotate the UCS about the x-axis and set the angle of rotation to 90 degree, Figure 8-24j.


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Figure 8-24j

• Create a cylinder with the center point of the base at (0,0,0), a base radius of 1 inch, and a height of 4 inches, Figure 8-25a.

Figure 8-25a

• Create a cone with the center point of the base at (0,0,4), a base radius equal to 1 inch, a top radius equal to 2 inches, and a height equal to 2.5 inches, Figure 8-25b.

• Note: The cone is created without moving the origin of the UCS. Although, an object can be created with respect to the current location of the UCS, the object creation process is simplified if the UCS is moved first to the desired location; create the object at the origin.


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Figure 8-25b

• Select Origin option from the UCS toolbar; and set the origin of the UCS at (-12,0,-4.5).

• Select Y option from the UCS toolbar to rotate the UCS about y-axis and set the angle of rotation to 90 degree.

• Create a cone with center point of the base at (0,0,0), base radius = 0.5 inch and height = 24 inches, Figure 8-25c.

Figure 8-25c

• Select the Origin option from the UCS toolbar; and set the origin of the UCS at (0,0,6).

• Create a cylinder with the center point of the base at (0,0,0), a base radius of 3 inches, and a height of 12 inches, Figure 8-25d.


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Figure 8-25d

• Create a cylinder with the center point of the base at (0,-2,0), a base radius of 0.25 inches, and a height of 12 inches, Figure 8-26a.

Figure 8-26a

• Create a polar array of the cylinder created in the previous step with 10 elements in the array. The center of the array is the origin of the current UCS, Figure 8-26b.

• Subtract the small cylinders from the big cylinder to create holes, Figure 8-26c.


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Figure 8-26b

Figure 8-26c

8.22.2. Example #3 Create the object shown in Figure 8-28.

• The user does not show dimensions on a 3D object.



• Set the visual style to the 3D Hidden style.


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• Turn on the ORTHO mode.

• (i) Activate the Box command. (ii) Specify the first corner at (0,0,0). (iii) Choose the length option. (iv) Specify the length as 400, width as 250, and height as 50, Figure 8-27a.

Figure 8-27a


• (i) Activate the Box command. (ii) Specify the first corner at (0,0,0). (iii) Choose the length option. (iv) Specify the length as 350, width as 200, and height as 50, Figure 8-27b.

Figure 8-27b


• (i) Activate the Wedge command. (ii) Specify the first corner at (0,0,0). (iii) Choose the length option. (iv) Specify the length as 150, width as 150, and height as 175, Figure 8-27c.


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Figure 8-27c

• (i) Activate the Wedge command. (ii) Specify the first corner at (0,0,0). (iii) Choose the length option. (iv) Specify the length as -150, width as 150, and height as 175, Figure 8-27d.

Figure 8-27d

• Select the 3 Point option from the UCS toolbar; and set the origin of the UCS at as shown Figure 8-27e.

• Create a cylinder with the center point of the base at (75,100,0), a base radius of 40, and a height of 80, Figure 8-27f.


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Figure 8-24e

Figure 8-27f

• Select the 3 Point option from the UCS toolbar; and set the origin of the UCS at as shown Figure 8-27g.

• Create a cylinder with the center point of the base at (75,20,0), a base radius of 20, and a height of 150, Figure 8-27h.

Figure 8-25g Figure 8-25h


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• Subtract both cylinders from the wedges. The resultant object is shown in Figure 8-28.

Figure 8-28

978-1-58503-392-8 -- tools for design - sdc …...figure 8-1a figure 8-1b figure 8-1b 8.3. 3d solid...

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