Working Drawings and Assemblies

1.   Define working drawings. p. 580

2.   Describe how working drawings are used in industry. pp. 582-592

3.   List the major components of a complete set of working drawings.  p. 582

4.   Describe the differences between detail and assembly drawings. pp. 582-592

5.   Describe how part numbers, zoning, and tables are used on working drawings. pp. 582-592

6.   Draw standard representations of threads. p. 604

7.   Specify a metric or English thread in a note. p. 597

8.   Use the graphic language of mechanisms such as gears, cams, bearings, and linkages. pp. 610-612

9.   Interpret the specialized graphic language used in welding drawings. pp. 612-615

10. Describe the process of creating assembly models in modern CAD systems. p. 576

11. Differentiate between top-down modeling and bottom-up modeling techniques for  assembly. pp. 617-619

12.  Describe file formats used in current model data exchange and archival  practices. pp. 617-619

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1.   Define working drawings.

A process of conceiving or inventing ideas mentally and communicating them to others. p564

2.   List the types of drawings commonly found in a complete set of working drawings.

A process normally associated with an entire business or enterprise which involves the development, manufacture, sale, and maintenance of a product. p566

3.   List the types of assembly drawings.

All types of analysis which concerns the functionality of the product (e.g. property analysis, mechanism analysis, human factors analysis). pp564-566

4.   Describe a family of parts.

An analysis which evaluates a design based on aesthetic and emotional qualities such as form, color, and symbolism. pp564-565

5.   What type of drawing is used for a family of parts?

The process used to formally record and communicate the final design solution. p595-596

6.   Define a subassembly.

The communication medium, often multiview and assembly drawings, between design and manufacturing. pp596-597

7.   What is zoning?

p567

8.   List the important items in a parts list.

9.   List the important items in a title block.

Text, illustrations, and other visual aids used when making an oral report to a group. pp590-591

10. What is a revision block?

11. Describe how CAD is used to create working drawings.

p567

12. Define fastening.

p596

13. Identify the different parts of the following thread note: ½-13UNC-2B.

A design process whose goal is products which are simpler to fabricate and assemble while still meeting its functional goals. pp568, 604

14. Sketch and identify the three methods of representing threads on engineering drawings.

15. Describe how CAD can be used to represent fasteners on a drawing.

16. Sketch the five basic types of welded joints and name them.

17. There are eight basic parts to a welding symbol. Sketch and name the eight parts.

18. Describe three CAD neutral files for data exchange. 

Geometric Dimensioning and Tolerancing

1. Identify and apply geometric dimensioning and tolerancing symbols on engineering drawings. pp. 546-547

2.   Select and place datums on parts. pp. 550-553

3.   Apply geometric controls on parts. pp. 552-562

4.   Apply the five-step GDT process to the design of a part. p. 563

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1.   What is MMC?

Working, or production drawings are specialized engineering drawings that provide the information required to make the part or assembly of the final design. p490

2.   What is the term for the theoretical size of a feature?

A detail drawing of each nonstandard part. An assembly or subassembly drawing. A bill of materials. A title block. p491

3.   Describe the difference between the MMC condition of a shaft and the MMC condition of a hole.

An outline assembly, a sectioned assembly, and a pictorial assembly. p493, 495

4.   How does a shaft depart from MMC? How does a hole depart from MMC?

A group of similar parts which may share common geometry and/or function. p504

5.   What is the difference between a datum and a datum feature?

Tabular drawings. p504

He even was influential in coining the term “engineering drawing.” p530

Dimensioning and Tolerancing Practices

1. Apply the standard dimensioning practices for mechanical drawings. pp. 490-493

2. Differentiate between current ASME standards and past practices for dimensioning. pp. 494-499

3.   Apply English and metric tolerances to dimensions. pp. 506-520

4.   Calculate standard tolerances for precision fits. pp. 510-511

5.   Apply tolerances using the basic shaft and basic hole systems. pp. 510-519

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1.   How are concentric circles best dimensioned?

In their rectilinear view. p444

2.   Sketch the symbols for diameter, radius, depth, counterbore, countersink, and square.

3.   Where are these symbols placed with respect to their numerical values?

Before. p444

4.   What is the primary difference between counterbore and spotface?

Depth of the counterbore. p444

5.   When is a small cross required at the center of a radius?

When the arc is not clearly defined as being tangent to other dimensional features. p442

6.   Define the depth of a blind hole.

It is the depth of the full diameter, not to the point. p444

7.   When are angled extension lines used? Sketch an example.

When space is limited. p441.

8.   When should extension lines be broken?

When passing through an arrowhead. p444

9.   How is a reference dimension identified?

It is enclosed in parentheses. p437

10. How can you tell if a dimension is out of scale (without measuring the drawing)?

The dimension value is underlined. p444

11. Write a note showing that a .25-inch-deep, .875-inch-diameter hole is to be repeated six times.

12. When is an arc dimensioned with a diameter, and when is one dimensioned with a radius?

A radius will have an 'R' preceding the dimension values whereas a diameter will have an 'ø' preceding the dimension value. p446

13. When should the word “drill” replace the word “diameter” when dimensioning a hole?

Never, according the current ASME standards. p446

14. What is the proper proportion of width to length of arrowheads?

Three times longer than they are wide. p437

15. What is the difference between limit dimensioning and plus and minus dimensioning?

Limit dimensions specify the maximum and minimum sizes as part of the dimension. With plus and minus dimensions, the basic size is given, followed by a plus/minus and a tolerance value. p457. p460

16. What is the term for the theoretical size of a feature?

The basic size. p459

17. Compare the thickness of dimension lines to object lines.

They are thinner. p446

18. Compare the thickness of dimension lines to extension lines.

They are the same. p446

19. If two dimensioning guidelines appear to conflict, which guideline should be followed?

Which ever method most clearly communicates the size information will prevail. p451

20. Write a definition of what Rule 1 means for a drawing of a flat washer with a 0.500 diameter ID, 1.000 diameter OD, and a thickness of 0.062. Use a tolerance of plus or minus 0.005.

Section Views

1.Apply the concept of cutting plans to create section views and sectioned 3-D CAD models. pp. 432-436

2.Represent cutting plane lines and section lines using conventional practices. pp. 432-439

3.Create full, half, offset, removed, revolved, broken-out, auxiliary, and assembly section views, using conventional practices. pp. 439-444

4.Create conventional breaks for different materials and cross sections. p. 453

5.Represent ribs, webs, and thin features in section, using conventional practices. p. 450

6.Represent aligned sectioned features, using conventional practices. p. 450

7.Apply section theory to computer models when designing. p. 453

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1.   Define section drawings.

Section drawings are multiview technical drawings that contain special views of a part or parts, views that reveal interior features. p387

2.   Describe how 3-D CAD is used to create section views.

Boolean operations are used to cut the model using planes or solids. p391

3.   Describe how cutting plane lines are used.

Cutting plane lines represent the edge view of the cutting plane and are drawn in the adjacent view to the section view. p391

4.   Sketch the two standard types of cutting plane lines.

p393

5.   List three applications of section views.

Roadway sections, technical illustrations, production drawings. pp387-389

6.   What convention is used for hidden lines in a section view?

Only use hidden lines when they are necessary to show a hidden feature not part of the section. pp398-399

7.   What convention is used for hidden lines on the unsectioned half of a half-section view?

Hidden lines are often added to show hidden features obscured on the sectioned half. p401

8.   Define section lines.

Section lines indicate the material which has been cut by the imaginary cutting plane. pp396

9.   Sketch the material symbol used to represent steel.

p396

10. Describe how thin parts are represented in a section view.

They are not sectioned. pp397-398

11. Describe the difference between a revolved and a removed section view.

A revolved section is made by revolving a cross section view 90° about an axis of revolution and superimposing the section view on the orthographic view.  A removed section is similar except the view is removed to another part of the drawing. pp403-405

12. List some of the standard parts that are not sectioned in an assembly section. Explain why.

Shafts, bearings, ribs, washers, gaskets, rivets, and pins. p405

13. What type of line is used to separate the sectioned half from the unsectioned half of a half-section view?

Pictorial Projections

1.   Define axonometric, isometric, dimetric, and trimetric projection. p. 376

2.   Explain the difference between an isometric projection and an isometric sketch. p. 379

3.   Create an isometric sketch. pp. 382-383

4.   Apply the theory of oblique projection to create oblique sketches. pp. 395-399

5.   Create a one-point perspective sketch. p. 409

6.   Describe one-, two-, and three-point perspective projection theory. pp. 404-406

7.   Define horizon line, station point, picture plane, vanishing point, and ground line. pp. 403-404

8.   Describe and draw bird's eye, human's eye, ground's eye, and worm's eye views. pp. 403-404

9.   Describe the four perspective variables that are determined before creating a perspective sketch. pp. 406-407

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1      Define oblique projection.

Oblique project is a form of parallel projection in which the projectors are parallel to each other but not perpendicular (i.e. oblique) to the plane of projection. p356

2.     List and describe the differences between the three types of oblique drawing.

A cavalier oblique is drawn true length along the receding axis while a cabinet oblique is drawn at half scale along the receding axis.  A general oblique can be drawn anywhere from full to half scale along the receding axis. p358, 360

3.     Define axonometric.

A parallel projection technique used to create a pictorial drawing of an object by rotating the object about an axis relative to the projection plane. p338

4.     Define isometric, dimetric, and trimetric drawings.

All three are axonometric drawings.  An isometric drawing uses a single scale to measure all three dimensions are whose axes are equal angles apart.  A dimetric drawing uses two scales and has two angles which are equal.  A trimetric drawing uses three scales and three different angles. p338-339

5.     Sketch the axes used for an isometric drawing.

6.     Sketch the axes used for regular, reversed, and long axis isometric drawings.

7.     What is the general rule used for hidden lines in isometric drawings?

Hidden lines are omitted unless they are absolutely needed to completely describe the object. p343

8.     Give examples of pictorial drawings used in industry.

9.     Sketch an isometric cube, then show how isometric ellipses would be drawn on each face of the cube.  Add center lines to the ellipses.

10.   What are the three angular measurements of isometric drawing axes?

120°. p342

11.   Describe perspective projection theory.  Use sketches if necessary.

Perspective projection attempts to create, as a two-dimensional projection, what a scene or object would look like as perceived by the human eye.  To do so, it must represent the fact that objects are perceived as being smaller in the distance and that parallel lines that recede in depth will converge on a imaginary point on the horizon. p362

12.   Identify the horizon line, station point, picture plane, vanishing point, and ground line in Figure 7.59.

13.   Sketch and label bird’s eye, human’s eye, ground’s eye, and worm’s eye views.

14.     List the four perspective variables that should be considered before drawing a perspective view.

Distance of the object from the picture plane, position of the station point, position of the ground line relative to the horizon, and number of vanishing points. p367

15.     Name the person who is generally given credit for systematizing isometric drawings. 

Auxiliary Views

1.      Create auxiliary views of inclined planes. pp. 343-346

2.      Use reference planes and fold lines when creating auxiliary views. p. 340

3.      Explain auxiliary view projection theory. p. 340

4.      Define primary, secondary, and tertiary auxiliary views. pp. 342-343

5.      Define width, height, and depth auxiliary views. p. 343

6.      Create successive auxiliary views. p. 352

7.   Solve dihedral angle problems. p. 351

8.   Create a partial auxiliary view. p. 347

9.   Plot curves in auxiliary views. p. 347

10. Use auxiliary views for reverse construction. p. 350

11. Create a view in a specified direction using auxiliary views. p. 350

12. Understand the difference between 2-D methods and 3-D CAD in creating auxiliary views. p. 348

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1.   Define auxiliary views.

An orthographic view that is projected onto a plane other than one of the six principal planes of projection.  This technique is used to show inclined and oblique surfaces and features in their true size and shape. p312

2.   Define primary, secondary, and tertiary auxiliary views.

An auxiliary view is created by defining a new line of sight relative to the object.  This creates the possibility of a series of successive views, each defined with a line of sight relative to the last view.  The first view created in this manner is the primary auxiliary view, the next, the secondary view, and so on. p315

3.   Define width, height, and depth auxiliary views.

Views are also named by the primary dimension taken from the measuring view, perpendicular to the fold or reference line. p316-318

4.   Explain how to find a view in a specified direction.

The point of view of the line of sight must be found.  This done by first creating an auxiliary view with a fold line parallel to the projected oblique line of sight in one of the views.  A secondary auxiliary view is then created with a fold line perpendicular to the line of sight.  This creates a point view of the line of sight and the desired view of the object. p323

5.   What is a partial auxiliary view?

When only the details of the inclined (or oblique) surface are projected and drawn in the auxiliary view, the view is called a partial auxiliary view. p320

6.   List the five applications for auxiliary views.

Reverse construction, true length of a line, point view of a line, edge view of a line, and true size of a plane. p322-323

7.   Describe how to find the true angular measurement for a dihedral angle.

The point view of the line of intersection between the two planes creating the angle must be found.  The steps described in question 4 are then taken to create the secondary auxiliary view. p324

Multiview

1.   Explain orthographic and multiview projection. pp. 215-218

2.   Identify frontal, horizontal, and profile planes. pp. 218-219

3.   Identify the six principal views and the three space dimensions. pp. 224-225

4.   Apply standard line practices to multiview drawings and sketches. p. 228

5.   Create a multiview drawing by sketching or CAD. pp. 231-240

6.   Identify normal, inclined, and oblique planes in multiview drawings. pp. 248-250

7.   Represent lines, curves, surfaces, holes, fillets, rounds, chamfers, runouts, and ellipses multiview sketches. pp. 251-262

8.   Explain the importance of multiviews. pp. 219-222

9.   Identify limiting elements, hidden features, and the intersection of two planes in multiviews. pp. 251-262

10. Apply visualization by solids and surfaces to multiviews. pp. 282-286

11. Visualize 3-D objects as multiview projections. pp. 271-282

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1.   Define orthographic projection.

A parallel projection technique in which the plane of projection is positioned between the observer and the object and is perpendicular to the parallel lines of sight. p197

2.   How is orthographic projection different from perspective projection?  Use a sketch to highlight the differences.

Perspective projection places the viewer at a finite (rather than infinite) distance from the object.  Being a finite distance away creates projection lines which are not parallel and create distortions in the projected object which mimic how the object is perceived.  pp197-198

3.   Define multiview drawings. Make a simple multiview sketch of an object.

Multiview drawings use orthographic projection to create two or more views of an object (three is standard).  The views of the object are defined by the positions of the planes of projection relative to the object. p199-201

4.   Define frontal, horizontal, and profile planes.

The frontal plane is typically the first plane established and shows the width and height dimensions of the object.  The horizontal plane shows the depth and width dimensions while the profile plane shows the depth and height dimensions.  The planes are all mutually perpendicular. pp199-201

5.   List the six principal views.

Front, top, right side, left side, bottom, and back. pp202-204

6.   Define fold lines.

The imaginary hinged edges of the glass box between the planes of projection.  They are labeled on the drawing by the initials of the planes of projection (e.g. the fold line between the horizontal and frontal planes would be labeled H/F). p204

7.   List the space dimensions found on a front view, top view, and profile view.

Front: width and height; top: width and depth; profile (right and left side): depth and height. p205

8.   Define a normal plane.

A surface which is parallel to one of the three principal planes of projection and perpendicular to the other two.  This surface will be seen in its true size and shape in one view and as edges in the other two. p227

9.   Define an inclined plane.

A surface which is perpendicular to one of the three principal planes of projection and inclined to the other two.  This surface will be seen as an edge in one of the views and foreshortened in the other two. p229

10. Define an oblique plane.

A surface which is inclined (not parallel) to all three principal planes of projection.  This surface will be seen foreshortened in all principal views. p229

11. List the eight rules of orthographic projection.

Listed in Summary, p267.

12. Why is visualization important in engineering and technical graphics? Is it useful in any other fields? Are you born with the ability to visualize, or is it learned?

Visualization is critical to being able to formulate and solve spatial/graphic problems mentally.  It also assists in planning the construction of drawings, sketches, and CAD models.  You are both born with, and can develop, visualization ability. p246

13. What is the relationship between faces and edges in the visualization of an object?

Edges are the lines that form the boundary between two faces of an object. pp249-250

14. Do planar and curved surfaces reveal themselves differently on an object?

Curved surfaces reveal limiting elements which represent the farthest outside feature of the curved surface. p250

15. Explain the different visual results of additive and subtractive combinations of two solids.  Are there ways of arranging additive or subtractive combinations such that the resulting object doesn't look any different?

The additive combination of two solids shows the resultant unique volume occupied by both the original solids.  With a subtractive combination, the result shows the overlapping volume of the two solids removed from the first solid.  If the second (subtractive) volume is a null object, the result would be the same. pp251-252

16. What are the differences in the way normal, inclined, and oblique faces are visualized?  How are cutting planes used to generate these faces?

A normal face is seen in its true size and shape while the inclined and oblique faces are seen foreshortened along either one or two of their axes, respectively.  A cutting plane parallel to one of the primary projection planes of an object will create a normal face.  If this cutting plane is rotated about one axis, it will create an inclined face, while if it is rotated about two axes, it will create an oblique face. pp253-254

17. Define a development.  How is it used in visualization?

A development can be thought of the flattened skin of a solid.  Developments are used to visualize the true size an shape of faces and the relationship of faces to each other on the object.  Developments can also be used to show the differences between planar, single-curved, and double--curved surfaces. pp257-258

      18. Name the person credited with demonstrating multiview projections in a book published in 1528. 

Modeling

1.   Understand the terminology used in 3-D modeling. All sections.

2.   Define the most common types of 3-D modeling systems. p. 156

3.  Describe the similarities and differences between constraint-based modeling and direct modeling. p. 156

4.   Apply Boolean operations to 3-D objects. p. 153

5.  Understand the role that planning plays in building a constraint-based model. p. 157

6.  Understand how feature order affects feature editing and final model geometry. pp. 174-175

7.   Apply generalized sweeps to the creation of model features. pp. 161-163

8.   Apply construction geometry in the support of feature creation. pp. 163-164

9.   Apply constraints to a feature profile. p. 156

10. Apply feature duplication to model construction. p. 178

11. Identify the elements used to define a view of a 3-D model. p. 180

12. Understand how model data associativity supports engineering design and analysis. pp. 153-154

13. Generate 2-D documentation from a 3-D model. pp. 183-184

14. Construct assemblies from part and subassembly models. pp. 170-180

15.  Define the types of analyses that can be used with 3-D models. pp. 185-187

16.  Understand how CAM information is derived from 3-D models. pp. 185-187

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1.   What is a nonmanifold object? Sketch an example of one.

Manifold objects unambiguously divide a region into inside and outside. Nonmanifold objects don't do this. p134

2.   Describe the differences and similarities between B-rep models and CSG models; do the same for wireframe models and B-rep models.

CSG models use solid primitives and half spaces related by Boolean operations in a binary tree data structure.  B-rep models define a solid region by surfaces, edges, and vertices.  Wireframe models do not define a volume, but describe just the edges and vertices of a 3-D model. pp135-138

3.   Define the three types of Boolean operations, and sketch examples of each one. Can you derive the same final object using different Boolean operations and/or primitives?

p137

4.   What is "design intent"? Why does this play a role in planning the construction of a constraint-based model?

Changes in geometry of a feature should create model feedback or further changes in the model which reflect design performance or manufacturing constraints of the product. p139

5.   What is the difference between unidirectional and bidirectional associativity? What are the advantages and disadvantages of bidirectional associativity?

In a sweeping operation, a closed polygon, called a profile, is drawn on a plane and is moved or swept along a defined path for a defined length.  Linear, revolved, path-based, and blend. pp142-3

6.   What are the basic elements of a generalized sweep? Describe the major types of generalized sweeps used in feature creation.

Workplanes define the location and orientation of the profile sketch and construction geometry relative to the model and world coordinate system. Through, Offset/parallel, Angle, Point or edge and orientation, Tangent and orientation, Axes and points.  p143

7.   What are sketch planes used for? What are five ways a sketch plane can be defined?

These two types of constraints differ as to whether the modeling system infers the constraint based on the way the sketch was drawn, or whether the operator has to explicitly apply the constraint to the sketch. Closure (connected edges), Segment overlap, Endpoint/line overlap, Tangency, Parallelism, perpendicularity, Same size, Coincident.  pp147-8

8.   Give an example of a parent-child relationship. How is a feature tree used to identify parent-child relationships?

A child feature is defined relative to a parent feature through geometric definitions such as constraints, alignment, or workplanes.  Child features exist below their parent features on a feature tree.  pp159-160

9.   What are the two primary types of duplication methods? What input parameters are needed to define each one?

Linear and radial arrays.  Linear arrays need the number of copies to be made in each of two orthogonal dimensions and the offset in each of these dimensions.  Radial arrays need a rotation axis, radial distance from the axis, number of copies, and the angular offset.  p162

10. What are the elements used to define a view of a 3-D model? Which types of view commands don't change the projection of the model?

Model (object), viewer (camera), and projection (view) plane.  Panning and zooming don't change the projection in parallel projection.  pp163, 166

11. How is the base view used in generating multiviews from a 3-D model?

With unidirectional associativity, the supporting application’s data can be altered by changing the 3-D model, but not vice versa. With bi-directional associativity, changes in either the 3-D model or data in the supporting application will affect the other.  p163-164

12. Define the types of analyses that can be used with 3-D models. Will all of these always be used when designing a part?

13.  What advantages are there for using data from a 3-D model when analyzing the manufacture of a part?