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13

Chapter ObjectivesIdentify types of working drawings.Understand the parts of working drawings and their layout.Set up a working drawing using board and CAD techniques.Create detail drawings, assembly drawings, and assembly working drawings.Design and draw a title block.Develop a bill of materials.

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Section 13.1Understanding Working Drawings

Section 13.2Preparing a Working Drawing

Working Drawings

Developing 21st Century Auto Concepts Welburn started at GM in an entry-level position and is now its top designer. He is clearly a distinguished professional. What personal characteristics do you think enabled him to reach this position?

456

Drafting Career

When he heard some years back that his General Motors bosses wanted to develop a 1,000-horsepower racer to break the land-speed record, Ed Welburn dashed off a teardrop-shaped road rocket design on a napkin and handed it to his boss, who declared: “This is it!” And Ed’s Aerotech was it.

Today, Welburn is vice president of global design

for GM. He tells his design staff to take risks to see their wildest dream cars on the road. On the horizon could be electric cars and designs reminiscent of the Aerotech or other futuristic concepts—but preferably not handed to him on napkins!

Academic Skills and AbilitiesMath, especially precalculus or calculusLanguage artsScienceSocial studiesForeign languageComputer technology

Career PathwaysA bachelor’s degree in design and a good portfolio

are required to obtain most entry-level positions in product design. Advancement generally requires one to three years of training. Creativity, technical knowledge, and a strong sense of aesthetics, detail, balance, and proportion are crucial.

••••••

Go to glencoe.com for this book’s OLC to learn more about Ed Welburn.

Ed Welburn, Product Designer

457General Motors/Joe Polimeni/Handout/Reuters/Corbis

http://www.glencoe.com

Understanding Working Drawings13.1

Preview Working drawings give complete information needed to build a single part or a complete object. What type would you use that could go, for example, to both a welder and an electrician?

Content Vocabulary• working

drawing• detail

drawing

• combination drawing

• tabulated drawing

• assembly drawing

• assembly working drawing

• reference assembly drawing

• bill of materials

• FAO

Academic VocabularyLearning these words while you read this section will also help you in your other subjects and tests.• assemble • formats

Graphic Organizer

Use a table like the one below to organize notes about working drawings.

Go to glencoe.com for this book’s OLC for a downloadable version of this graphic organizer.

Type of

Working Drawings

Parts of a Working Drawing

Academic Standards

English Language Arts

Read text to acquire new information (NCTE)

Mathematics

Use mathematics to express mathematical ideas precisely (NCTM)

ADDA Section 4

Drawing Types (ASME Y14.24, Y32.10)

NCTE National Council of Teachers of English

NCTM National Council of Teachers of Mathematics

ADDA American Design Drafting Association

ASME American Society of Mechanical Engineers

Industry Standards

458 Chapter 13 Working Drawings


A

O2.5642.562

O

T

.58.38–18 NPSASME B1.20.1

.38

.38

.25

R.56

.50

1.00

R.75

.66

4.50

2.75

O .25 THRU TOP WALLOF BUSHING ONLY

45°.12

3.75.88

.75

O .55 THRU ONEWALL OFBUSHING

. 38 .53(HOUSINGONLY)

O

3.253.50

6.50

OO .50 THRU CAP ONLY .42 THRU BASE ONLY.50–13 UNC–2B THRU FOR.50–13 X 1.75 HEX HD CAP SCREW WITH MEDIUM–SPRING LOCK WASHER

R.12

R.12 R.12

1.00.50

.75

R.12 .12

.38

FILLETS AND ROUNDS R.25EXCEPT WHERE NOTED

.75

1.88

130°

R.12

R1.75O.38

O.50.56

.312.12

.50.12

3.008.50

O2.19602.1940

DODGE MANUFACTURING CORP.MISHAWAK, INDIANA

SPLIT BRONZE BUSHEDJOURNAL BEARING

BUSHING FAO

B

Types of Working Drawings What types of drawings are needed to manufacture a product?

A working drawing must give all infor-mation needed to manufacture or build a part or a complete machine or structure. It has to identify precisely the required shape and size of the fi nished product. It also specifi es the materials, fi nish, and degree of accuracy required. In addition, it provides all necessary information to assemble the fi nal product.

Working drawings are usually multiview drawings with complete dimensions and notes added. See Figure 13-1 for an example. These

drawings become critical working documents for the production of parts and products.

A good working drawing follows the style and practices of the industry in which it is made. Most industries follow ASME-recommended standards. Because of these standards, plans can be easily read and under-stood from one industry to another.

Detail DrawingsA drawing of a single piece that gives all

information for making it is called a detail drawing. An example is the drawing of a sim-ple part in Figure 13-2. A detail drawing must be a full and exact description of the piece. It should show carefully selected views and include well-placed dimensions (see Figure 13-3).

Figure 13-1

(A) A working drawing for a split bronze-bushed journal bearing and (B) the bearing described in the working drawing

Section 13.1 Understanding Working Drawings 459

1 2 3 4 5 6

1 2 3 4 5

A

B

C

D

E

F

A

B

C

D

E

F

2 S 3 0 4 8

2 S 3 0 4 8

I E 4 2 1 H O L E TO L

I 3 5 7 H R S T E E L

3 . 5 m m T H K

N OT E S :

DIMENSIONS INMILLIMETERS

TOL - 0 .5+

C AT E R P I L L A R

P L AT E – T O P B A F F L ES C A L E - 1 : 1

P EDES CONTROL

FORM NO. GP 126-/616-/

HEAT TREATMENT

MATERIAL

THIS PRINT IS THE PROPERTY OF CATERPILLAR TRACTOR CO.AND/OR ITS SUBSIDIARIES AND MUST NOT BE USED IN ANYMANNER DETRIMENTAL TO THEIR INTERESTS.

CHG DATE

DATE

DRN

CHK

APPD.

PROVE DES PROD.

1 NOV. 8,

REMOVE BURRS

O10.52 HOLES

O52 HOLES

5028

12

3.560

84

12

SECTION A–A

.75 NPT, ASME B1.20.1

FAOMATERIAL: 1034 STEEL

9.505.88(1.50)

1.25OO

2.0042.002

O2.9902.982 2 .22O

.50O

1.75O

1.50A

.38

A3.00.12 X 45 °

60°1.25O

R.0630° CHAMFER

30°.25

.06 X 45 °

1.88

R .12M 52ASME B1.13M

SPECIAL ADAPTER

COMPANY PLACEDRAWN CHECKED DATE A.B.C. G.H.I. 12 - 22 -

TRACED APPROVED SCALE D.E.F. J.K.L.

1.00

1.75

A B

When a large number of machines are to be produced, detail drawings of each part are often made on separate sheets, especially when a part is used on more than one machine. In some industries, however, several parts of a machine are detailed on the same sheet. Some-times a separate detail drawing is made for each of several workers involved, such as the pattern maker, machinist, and welder. This sep-arate drawing shows the dimensions and infor-mation needed by only the worker for whom it is made. Figure 13-4 shows an index-plunger operating handle. This fi gure shows the piece as a forged handle (A) and after it has been

Figure 13-2

A detail drawing

Figure 13-3

A single view and an extra section provide a complete description of this special adapter.

Figure 13-4

(A) A forged index-plunger operating handle and (B) the same handle after machining


Courtesy of the H

artford S

pecial M

achinery Com

pany

4.00

1.00.50

10°1.10

10°

.12.24 O1.50

O.8810°

.72

.601.44 1.34

4.00 .05

1.24

O1.0921.085

UNLESS OTHERWISE SPECIFIED FINISH ISTOLERANCE ON DIMENSIONS

32

.02

O.936.930

O1.76O1.00

.80

.68

1.60

(A) FORGING DRAWING (B) MACHINE DRAWING FOR FORGED

PART SHOWN IN (A)

machined (B). Figure 13-5 shows a detail drawing of the same piece. Notice that the drawing shows the part after the machining process has removed the material. Notice also the detailed list of machine operations.

Figure 13-5

Working drawing of the part shown in Figure 13-4

Figure 13-6 shows a two-part detail draw-ing known as a combination drawing. Onehalf gives the dimensions for the forging. The other half gives the machining dimensions and notes.

Figure 13-6

Two-part detail drawing showing separate information for forging and machining


A

C

E

D

E

B

BUSHING

PARTNO. A B C D E

CB 1 1.500 2.000 1.000 0.500 0.375

CB 2 1.625 2.125 1.125 0.625 0.437

CB 3 1.750 2.250 1.250 0.750 0.500

CB 4 1.875 2.375 1.375 0.875 0.562

CB 5 2.000 2.500 1.500 1.000 0.625

R10

74

64

Ø72

Ø42

.20

AMOUNT REQ'D

TOOL NO.

MATERIAL

REQ. NO.

57.6557.40Ø

38.1038.00Ø

12

CT-976-F

STEEL

E-1152

AMOUNT REQ'D

TOOL NO.

MATERIAL

REQ. NO.

A B

Figure 13-7

A tabulated drawing

Figure 13-8

Detail drawing of a standard part with dimensions blank (A) and fi lled in (B)

Detail drawings are often made for stan-dard parts that come in a range of sizes. A tabulated drawing is one in which the dimensions are identifi ed by letters. See Figure 13-7 for a tabulated drawing of a bushing. A table placed on the drawing identifi es what each dimension is for different sizes of the part. Either all or some of the dimensions can be given in this way. A similar type of draw-ing shows the views and leaves blank spaces for dimensions and notes (see Figure 13-8A). The required information is then entered on these blanks (see Figure 13-8B). The views in tabulated drawings are not to scale except per-haps for one size.

Explain How are dimensions identifi ed in a tabulated drawing?

Assembly DrawingsA drawing of a fully assembled construction

is called an assembly drawing. This shows how the parts fi t together, the look of the con-struction as a whole, the dimensions needed for installation, the space needed, and so forth. Such drawings vary greatly in terms of the completeness of detail and dimensioning.


PARTIAL TOP VIEW OF PART 1 ONLY

1.25

3.50

3.00

.40

.10 .60

.60 .36

5.20

R1.20

R.20

R.20

R1.20

R3.00

1.101.20

.4384 HOLES

.06 X 45°CHAMFER

.12 NPTASME 1.20.1

1.50

.40

1.00 -12UNF-2AASME B1.1

.60 CORE

1.00

4.00

2.601.20

1.40

3.00

8

3

4

7

.20

.16 3.00

1

5

62

3.20

.12

R1.20

O

O

1.80O 1.80O1.06O 2.00O

.50O

1.24O

2.60O

1.20O2.25O5.00O

.328O

2.804.004.00

.44

1

2

3

4

5

6

7

8

- FRAME

- SHAFT

- PULLEY

- COLLAR

- WASHER

- NUT

- BOLT

- WASHER

Figure 13-9

An assembly working drawing for a belt tightener

When an assembly drawing gives complete manufacturing information, it can be used as a working drawing. It is then called anassembly working drawing. This type of drawing is used only when there is little or no complex detail (see Figure 13-9).

Assembly drawings of machines are gen-erally made to a small scale. Dimensions are chosen to specify overall distances, impor-tant center-to-center distances, and local dimensions. All, or almost all, hidden lines may be omitted. Also, if the drawing is made to a very small scale, unnecessary detail may be omitted. This has been done, for exam-ple, in the drawing in Figure 13-10. Draw-ings in which details have been omitted are called outline assembly drawings. Either exte-rior or sectional views may be used. When the main purpose is to show only the gen-eral look of the construction, only one or two views need to be drawn. Because some

assembled constructions are large, you may need to draw different views on separate sheets. However, you must use the same scale on all sheets.

A reference assembly drawing is a spe-cial assembly drawing that identifi es parts to be assembled (see Figure 13-11). Note the material list in the upper right-hand corner and the dimensions shown.

Other types of assembly drawings made for special purposes include part assem-blies for groups of parts, drawings for use in assembling or erecting a machine, drawings to give directions for upkeep and use, and so forth.

Explain What is the purpose of an outline assembly drawing?


19

21

11

287

2526

9

20

21

29

23

12

17

323

31 1324

2418

16

17

5

11

61 8 22

10

2

4

1430

15

A

SECTION A–A

18.00

15.258.50

A

10.38

32.00

Ø12

24. 25–18 NPTASME B1.20.1

342

300

152

GCD

EF

A

B

44

26

50

MATERIAL LIST

1 1041Y33 FRAME F

1 2 3Y104 K FRAME BABBITED B

GROUP QUAN-REQ'D

PIECEOF

GROUP

NAME OF PART MATERIAL

SYM-BOL

2 HEX NUT C

1 126257 20 U - BOLT A

1 PIPE COUPLING G

1 PIPE NIPPLE E

2 LOCK WASHER D

DRAWING NO.

PART NUMBER

A

SCALE

DATE

DRAWING CHECKED APPROVED FORM REFERENCE

TITLE

DIMENSION TOLERANCES EXCEPT AS SPECIFIED

R W R L R N R C

R J

R D

R T

I M

O R

BRONZE CAP NOTE ADDED E.F.C.

PART No. 283Y112-C ADDED R.C.

GROUP B, NOTES & DIMENSIONS FOR

GROUP C, REMOVED - FRAME WAS

1041 Y 33 - B FOR GROUP C ONLY C.W.

No. 198 HANGER ASSEMBLY

REV DATE DESCRIPTION OF REVISION

C

B

A

LINK - BELT COMPANY 162Y259

162Y259

38

Figure 13-10

An outline assembly drawing

Figure 13-11

A reference assembly drawing of the hanger assembly shown in the pictorial view


Layout of Working Drawings What are the parts that make up a working drawing?

Whether you use board or CAD techniques, your drawings will be easier to draw and use if you set them up properly. For example, the views and scales you choose greatly affect the draw-ing’s readability. Therefore, you must take the time to plan the drawing before you begin.

Choosing ViewsThe views you choose should always be

those that are easiest to read. Each view you use must add information to the description of the object.

Though two views are usually suffi cient, complex pieces may require three or more views. As you plan the views you need, con-sider whether the additional views should be partial, auxiliary, or sectional.

If you have any question about which views to draw, think about why you are making the drawing. A drawing should clearly and precisely give the information needed for its purpose.

Choosing a ScaleThe scale for a detail drawing is chosen

according to three factors:

how large the drawing must be to show details clearlyhow large the drawing must be to include all dimensions without crowdingthe size of the paper

Whenever possible, an object should be drawn full size (1:1). Other scales that are com-monly used are half, quarter, and eighth. Avoid scales such as 1:6, 1:3, and 1:1.33. If a part is very small, you can draw it at an enlarged scale.

When you draw a number of details on one sheet, use the same scale if possible. If you must use different scales, note the scale near each drawing. It is often useful to draw a detail, or part detail, to a larger scale on the main drawing. This saves both time and effort in making separate detail drawings. For general assembly drawings, choose a scale that shows the details you want and looks good on the size of paper you are using.

•

•

•

For complete assemblies, a small scale is generally used. The scale is often fi xed by the size of the paper the company has chosen for assemblies. For part assemblies, choose a scale to suit the drawing’s purpose. This might be to show how parts fi t together, identify the parts, or explain an operation.

Grouping and Placing PartsAnother part of planning a set of working

drawings is deciding where to place each view or part on the drawing sheet. When many details are used for a single machine, it is often a good idea to group them on a single sheet or set of sheets. A convenient method is to group the forging details together, the materials details together, and so on. In general, show the parts in the positions they will occupy in the assembled machine. That way, related parts will appear near each other. Long pieces, however, sometimes must be drawn parallel to the long dimension of the sheet (see Figure 13-12).

Contrast What scale is used for general assembly and part assembly drawings?

Title BlocksEvery sketch or drawing must have some

type of title block to record important refer-ence details. The form, completeness, and location of the title block can vary. On work-ing drawings, it can be placed in a box in the lower right-hand corner (see Figure 13-13A),or it can be included in a record strip running as far as needed across the bottom or end of the sheet as in Figure 13-13B.

Most title blocks contain some or all of the following information:

name of the construction, machine, or projectname of the part or parts shown, or simple detailsmanufacturer, company, or fi rm name and addressdate (usually the date of completion)scale or scales usedheat treatment, working tolerances, and so forth

•

•

•

•••


O

O O

O

O

O

O

O

O O

O

O

O.75

.38

1.00

.12

.50

.6250

.62407.00

8.50

9.50

.50 X .12

.62–8 ACME–2GAASME B1.5

3

.48

2

.31

.10

FAO

5

S .62

.14ASSEMBLE ANDREAM FOR NO. 0TAPER PIN

.3804

.3800

4

6

2X .03 X 45

.14

.38

°

6.50

.50

8.00

.06 X 45°

.38–16UNC–2AASME B1.1

2XLOCATE AT ASSY

.34 X .12

.62

TECHNICAL GRAPHICS701 GREEN BELT ROAD – BROWNVILLE. PA 15417

WOODWORKING VISE

DWN BY: K. BAKOS DATE: 02/08/20--

SCALE: 1:1 DWG NO.

APPROVED: 03/02/20-- JDH2 OF 2

SR.94

CENTRAL TEXAS IRON WORKSWACO TEXAS ABILENE

BUILDING

LOCATION

CUSTOMER

ARCHITECT

MADE BY CHK. BY SHEET NO.DATE REVISIONS ORDER

NO.

RIVETS EXC. NOTED

HOLES EXC. NOTED

BLUEPRINT RECORD

NO. DATE ISSUED FOR

PAINT

DR. DATE SYMBOL OF MACHINES USED ON

DR.

TR.

TR. CH.

UNIT

THE LODGE & SHIPLEY MACHINE TOOL CO.CINCINNATI, OHIO. U. S. A.FORM 795

NAME OF PIECE

SUPERSEDES DRAW.

SUPERSEDED BY DR. MATERIAL PIECE NO.

STOCKCASTINGDROP FORGING

A

B

drawing number, shop order number, or customer’s order number, according to the system used by the companydrafting-room record: names and initials, with dates, of drafter and checker; approval of chief drafter, engineer, and so forth

A basic layout for a title block based on ASME standards is in Figure 13-14.

•

•

The title block can be preprinted on the drawing sheet or can be attached using a preprinted sticker. With CAD, the title block appears on the drawing template.

Change or Revision BlockA change or revision block is a table where

drawing revisions are recorded. It is attached to the title block (see Figure 13-11) or placed

Figure 13-12

Several machine parts drawn on one sheet

Figure 13-13

Title blocks: (A) boxed title and (B) strip title


OPTIONAL BLOCKFOR RECORD OFPRINT DISTRIBUTION

RESERVED FOR GENERAL NOTESAND OTHER INFORMATION(HEIGHT OF SPACE OR TITLE BLOCK AS REQUIRED)

SCALE,WEIGHT,SPECIFICATIONS,STD PRINTEDNOTES SUCH ASTOLERANCES,FINISHES,ETC.

TITLE OR NAME OF PART

SIGNATURE & APPROVALS

FIRM'S NAME AND ADDRESS

DRAWING NO.CONT ON SHEET

2.00(52)

2.50 (64)

1.50 (38) 4.25 (108)5.75 (146)

.25 (6)

.75 (20)

SHEET NO.

1.00 (26)

.50 (13)

.50 (13)

BILL OF MATERIALS FOR IDLER PULLEY

NAME REQD MATL NOTES

IDLER PULLEY 1 C1

IDLER PULLEY FRAME 1 C1

IDLER PULLEY BUSHING 1 BRO

IDLER PULLEY SHAFT 1 CRS

Ø.62 HEX NUT 1 PURCHASED

WOODRUFF KEY #405 1 PURCHASED

.12 OILER 1 PURCHASED

BILL OF MATERIALSGROUP NO. AND QUANTITY PART

NO.NAME DRAWING NO. OR DESCRIPTION

1.80

.30

.03

.40 1.40

7.60

.25

down the right-hand side or along the bot-tom of the drawing sheet. If the revision block header appears at the top of the sheet, revi-sions are listed and numbered consecutively from the top down. If it is at the bottom of the sheet (see Figure 13-11), the revisions are listed and numbered consecutively from the bottom up.

Bill of MaterialsMost working drawings include a list of parts,

the materials of which they are made, identifi -cation numbers, and other important informa-tion. On assembly drawings, this information is especially important, as well as on detail draw-ings that show several parts on one sheet.

The names of parts, materials, quantities, part numbers, and so forth are often given in notes near their views. It is better, however, to place only the part numbers near the views, link them to the views with leaders, and then place all other information in a tabulated list called a bill of materials. ASME’s offi cial term for this is a parts list. ASME provides formal speci-fi cations for a parts list, but other formatsare used. See Figure 13-15 for an example of a simple bill of materials. Figure 13-16 shows the recommended format. The column widths and names may vary as needed.

Figure 13-14

Basic layout for a title block. Dimensions shown are ASME recommendations and may vary to accommodate the user’s requirements.

Figure 13-15

A simple bill of materials

Figure 13-16

Recommended form for a bill of materials


For working drawings created using board drafting techniques, the bill of materials is usually placed above the title block or in the upper right corner of the sheet. It can also be written or typed on a separate sheet with a title such as “Bill of Materials for Drawing No. 00” to identify it. This method is espe-cially useful with CAD drawings.

Notes and Specifi cationsInformation that you cannot make clear

in a drawing must be given in lettered notes and symbols. Special trade details such as the following are often given in this way.

quantity neededmaterialtype of fi nishtype of fi tmethod of machiningtypes of screw threadstypes of bolts and nutssizes of wirethickness of sheet metal

•••••••••

The materials in general use are wood, plastic, cast iron, wrought iron, steel, brass, aluminum, and various alloys. All parts that go together must be of the proper size so that they will fi t. Pieces may be left rough, partly fi nished, or completely fi nished.

After a part has been cast or forged, it must be machined on all surfaces that are to fi t with other surfaces. Round surfaces are generally refi ned on a lathe. Flat surfaces are fi nished or smoothed on a planer, milling machine, or shaper. Holes are made with drill presses, bor-ing mills, or lathes. Extra metal is allowed for surfaces that are to be fi nished. To specify fi n-ish on surfaces, place a fi nish symbol on the lines that represent their edges. If the entire piece is to be fi nished, add a note such as FINISH ALL OVER, or FAO. No other mark is needed.

In current dimensioning practice, the drafter usually does not specify the method or tool to be used. Only the fi nished size and shape are given.

Section 13.1 AssessmentAfter You Read

Self-Check 1. Identify three types of working draw-

ings and their purposes. 2. Name all the parts of a working draw-

ing and explain their positions on the drawing sheet.

Academic Integration Mathematics

3. What would the clearance be for a hex nut where the constant is 1.155 with a measurement of .750 across the fl ats? What about a hex nut with a measure-ment of .475?

Use Variables and Operations

Use the formula c�1.55f. If necessary, refer to this chapter’s Do the Math.

Drafting Practice 4. Plan and draw the layout for an assem-

bly drawing of the cement fl oat shown in Figure 13-17. Block in space for the views and draw in the spaces for title block, revision block, and bill of mate-rials, as well as notes and specifi cations.

1 26

1

1 R

10

4

34 X 4 X 18

REDWOOD

1 4

11 4

2

1

1R

1 R

SECTION THROUGHHANDLE

WHITEOAKDRILL AND COUNTERSINK

FOR NO. 10 FH WOODSCREWS, 2 REQD

1 34

Figure 13-17

Go to glencoe.com for this book’s OLC for help with this drafting practice.



Preparing a Working Drawing13.2

Go to glencoe.com for this book’s OLC for a downloadable version of this graphic organizer.

Connect Here you will follow principles from the previous section to create a working drawing using both board-drafting and CAD techniques. What technique similarities and diff erences do you think you will fi nd?

Content Vocabulary• multiple layouts

Academic VocabularyLearning these words while you read this section will also help you in your other subjects and tests.• estimate

Graphic OrganizerUse a table like the one below to organize notes about working drawing board drafting and CAD techniques.

Steps in Creating a Working Drawing

1. 2. 3. 4.

5. 6. 7. 8.

Academic Standards

English Language Arts

Use language to accomplish individual purposes (NCTE)

Mathematics

Number and Operations Understand numbers, ways of representing numbers, relationships

among numbers, and number systems (NCTM)

Algebra Understand patterns, relationships, and functions (NCTM)

Science

Science in Personal and Social Perspectives Science and technology in local, national, global

challenges (NSES)

ADDA Section 3

Working Drawings

Industry Standards

NCTE National Council of Teachers of English

NCTM National Council of Teachers of Mathematics

NSES National Science Education Standards

ADDA American Design Drafting Association

Section 13.2 Preparing a Working Drawing 469


3

2

4

1

O.50

.25

.88.03 X 45° CHAMFER

MEDIUM DIAMOND KNURL

KNURLED SCREW, 2 REQD

10-32-UNC-2A X .50 LGASME B1.1

O.50 X 8.00

FLAT .20 WIDE

O.12 X 1.00DRILL ROD

SCRIBER

.25

BEAM1.50

.50

.20

O1.12

O2.00

HEAD

.06 X 45 CHAMFER°

.03 X 45° CHAMFERBOTH ENDS

R.12

Ø.50

Board-Drafting TechniquesWhy is it important to carefully plan the drawing layout before beginning a working drawing?

In preparing to make working drawings, drafters and students often fi nd developing a good layout of the various views on the sheet diffi cult. Sheet layout for a simple detail draw-ing is relatively easy. However, sheet layout for a drawing with several parts on one sheet is somewhat more diffi cult. With experience, you will fi nd preparation easier and less time consuming.

Regardless of how simple or complex the drawing is, some basic steps are necessary to develop it. This exercise gives you practice in setting up a working drawing of the marking gage shown in Figure 13-18. Follow these steps:

1. Develop a freehand sketch of the views you have chosen for the part or parts given. The sketches need not be to scale but estimate the sizes relatively close to the fi nished drawing size.

2. Add dimensions and notes to your sketches. This will help you determine the overall space needed for each view or drawing on the sheet.

3. Choose the appropriate scale based on the size and complexity of the part. You may have done this as part of step 1. However, at this point, you can make any necessary changes. For the marking gage, an appropriate scale is 1:1.

4. Determine the amount of space needed on the sheet for each part or view.

5. Select the sheet size that will best accom-modate your drawing. Try not to crowd the sheet, but do not select one that is excessively large. If you are working on a large and complex set of drawings, select one standard sheet size for the entire set

Figure 13-18

Marking gage


NO. NAME REQD MATL NOTES

BILL OF MATERIALS

TECHNICAL GRAPHICS701 Greenbelt Road – Brownsville, PA 15410

DWN BY: DATE:

SCALE:

APPROVED:

DWG NO. OF

of drawings. For the drawing in this exer-cise, we have chosen an A-size sheet.

6. Draw borderlines, title block, and bill of materials or parts list (if required). See Figure 13-19.

7. Block in spaces for the various views or parts (Figure 13-19). Use only very light layout lines for this purpose. For draw-ings of multiple parts, try to group draw-ings of individual parts according to where and how they fi t in the assembly of the fi nal product.

8. Develop the individual drawings in the spaces provided as in Figure 13-20.

9. Darken all lines, add general notes, and fi ll in the bill of materials as required.

Another method that may be used to develop a good sheet layout is fi rst to prepare rough mechanical drawings of each view or

part on separate sheets of paper. Then follow these steps:

1. Select a drawing sheet of appropriate size. Then rough in the borderlines, title block, and bill of materials or parts list, if required. This sheet will be used for lay-out purposes only.

2. Place the individual rough drawings on the layout sheet and move them around to develop a pleasing layout. Be sure to allow adequate space for general notes and other details as necessary.

3. Tape the individual rough drawings in place. Carefully review what you have done. Make certain that nothing has been missed in developing the rough draft.

4. Tape a piece of tracing material over the rough drawing. Trace the entire drawing. The result should appear as in Figure 13-20.

Figure 13-19

Sheet layout for a working drawing of the marking gage


4 SCRIBER 1 90 PT CARBON STL HARDEN

3 KNURLED SCREW 2 SAE 1050 STEEL

2 BEAM 1 SAE 1050 STEEL

1 HEAD 1 CAST IRON

NO. NAME REQD MATL NOTES

BILL OF MATERIALS

THREAD CONTROLLING ORGANIZATIONAND STANDARD–ASME B1.1-2003

TECHNICAL GRAPHICS701 Greenbelt Road – Brownsville, PA 15410

MARKING GAGE

DWN BY: K. BAKOS DATE: 06/08/20--

SCALE: 1:1

APPROVED: 06/11/20-- JDH

DWG NO.1 OF 1

1.00

.34

4 SCRIBER

.09

1 HEAD

10–32 UNC–2B

.50

Ø1.12

Ø2.00

R.12

.201.50

.06 X 45°CHAMFER

Ø.50

10-32 UNC-28X .70

2 BEAM

8.00

2X .06 X 45° CHAMFERØ.095

.25

Ø.50 .20

3 KNURLEDSCREW

2X .03 X 45° CHAMFERMEDIUM DIAMOND KNURL

10–32 UNC–2A X .50 LONG

Ø.50

.25.88

Ø.19

MARKING GAGE1

4 323

CAD TechniquesHow important is layout planning when working in CAD?

In most ways, working drawings are eas-ier to set up using a CAD system than using board-drafting techniques. Indeed, many companies that use CAD systems have their own drawing templates. However, you must still take care to set up the drawing correctly. CAD software cannot choose the correct views of an object for you, nor can it select

an appropriate scale. You must become profi -cient at these tasks.

Using LayersCAD systems greatly reduce the amount

of time needed to create a full set of working drawings, particularly when separate drawings are needed for various workers, such as electri-cal contractors and welders. You need to create the basic views only once in a CAD drawing. Then you place the information needed by each contractor on a separate layer. For exam-ple, you might place the basic views on a layer called Machine. Then you could include a Welding layer, an Electrical layer, and as many other layers as necessary to provide the appro-priate information to the various contrac-tors. Then to supply the drawings needed by the electrical contractor, you simply freeze all

Figure 13-20

Completed working drawing

Identify What is the fi rst step in setting up a working drawing?


A

B

of the layers for other contractors and either print the drawing or supply it to the contrac-tor electronically. You do not need to create an entirely new drawing for each purpose.

This approach also is often benefi cial from a record-keeping standpoint, too. By using layers to provide the various contractors with information, you are keeping all of this infor-mation in a single drawing fi le. You do not have to keep track of a large number of bulky drawings. Instead, you simply keep backups of the one drawing fi le.

Creating Multiple LayoutsThe AutoCAD software has the ability to

include one or more layout views in a draw-ing fi le. These multiple layouts are tabbed at the bottom of the drawing area in a man-ner similar to the worksheets in Microsoft Excel. By default, each drawing contains two layouts called Layout1 and Layout2. However, you can rename them and add as many lay-outs as you want. For example, in the drawing in Figure 13-21, the drafter has included fi ve

Figure 13-21

An entire set of working drawings can be included in a single drawing fi le by using custom layout views in paper space. (A) One of the layouts for a roller assembly. (B) Notice how the drafter has labeled each tab.


Displaying the Layout Tabs

In some versions of AutoCAD, the layout tabs may not be visible by default. If the tabs are missing, right-click the Model tab in the status bar and choose Display Layout and Model Tabs.

layouts to detail different parts of an assem-bly. You can see in the close-up of the tabs shown in Figure 13-21 that they have been given names that make the content of the lay-outs clear.

All of the layout views are in paper space and include the border and title block speci-fi ed by the drawing template. However, you can choose what parts of the model-space drawing to include in each layout. For exam-ple, in Figure 13-21, all four of the drawings shown in layout views actually exist in model space. The drafter simply chose to show differ-ent areas of model space in each layout view.

Creating a Working DrawingIn this section, you will create a working

drawing of the marking gage shown in Figure 13-18. The initial procedures are basically the same as those for creating any other CAD drawing. However, working drawings require more planning. As in board drafting, you must decide on an appropriate sheet size and scale. However, you should also consider the layers that will be needed and what informa-tion each layer will contain.

Keep in mind that you should label each layout so that others who use the fi le will understand immediately what each layout contains. Refer again to Figure 13-21. For the marking gage drawing, you could simply use one of the layout tabs for the entire working drawing. However, some industries require that separate drawing sheets be used for vari-ous views. Therefore, it is good to know how to use multiple layouts.

Follow these steps to create a working drawing:

1. Analyze the part or parts carefully to determine the views that will be needed. In the case of Figure 13-18, you will need two-view drawings of the head and beam, a two-view detail drawing of the knurled screw, a detail drawing of the scriber, and an assembly drawing shown in section.

2. Assume that the company you work for requires that orthographic drawings be drawn on a separate sheet from assem-bly drawings. Decide how many draw-ing sheets you will need. For the marking gage, you will need two layout sheets, one for the four orthographic drawings, and one for the assembly drawing.

3. Select an appropriate size for the drawing sheets. For the marking gage, we have selected an A-size drawing sheet. Auto-CAD allows you to set each layout on a different size sheet if you prefer, but this is not good practice. You should keep all pages of a set of working drawings on drawing sheets of the same size.

4. Decide what layers to use for the draw-ing. The layers you might want to cre-ate for the marking gage include Object lines, Dimensions, Centerlines, Hidden lines, Hatches, Border, and Title Block. (Note: In practice, layer names and con-tents are often specifi ed by the individual companies. In some cases, the layers are even set up in the company’s template drawings. You should check company guidelines before completing this step.)

5. Create a new drawing using an A-size template. Call the fi le Marking Gage.

6. If your version of AutoCAD does not include a standard A-size template, cre-ate an appropriate border and title block (see Figure 13-22).

7. Set up the layers that you have identi-fi ed as necessary, and set the text style to Roman Simplex.

Now you should set up the layout views. Follow these steps:

1. Right-click the Layout1 tab and select Rename. Name the layout Orthograph-ics. Note: If you used one of AutoCAD’s sheet-specifi c templates to create the new


VIEWPORT

fi le, the Layout1 and Layout2 tabs may have been replaced by a tab specifi c to the drawing sheet. Proceed as if this tab were named Layout1. For the second layout tab, right-click the fi rst one and select New Lay-out. Then proceed as described in Step 3.

2. Delete the default viewport and create a new one using a window to enclose most of the blank area on the drawing sheet as in Figure 13-22.

3. Repeat steps 1 and 2 for the other layout view. Name it Assembly.

Figure 13-22

Use a window to create a viewport that covers most of the blank space on the layout sheet.

F

C F = FLATS

C = CORNERS

CONSTANT = 1.155

.625

Calculating Corner Clearance

for a Hex NutWhen designing a product with a hex nut, care must be taken to ensure that there is clearance to tighten the nut in assembly.Find the corner clearance for a hex nut that is .625” across the fl ats, as show below.

Calculate corner clear-ance by determining the distance across the corners of a hexagon. Do this by using a formula that contains a constant, or unchanging value. In this case, the constant is 1.144, and the formula for determin-ing the distance across the corners when you know the distance across the fl ats is c=1.155f, as shown below.

Academic Standards

Mathematics

Algebra Understand patterns, relations, and functions

(NCTM)

For help with this math activity, go to this book’s OLC at glencoe.com and click on Math Handbook.



10-32 UNC-28X .70

1.00

.34

4 SCRIBER

.09

2 BEAM

8.00


.25

ø.50 .20

1 HEAD

3 KNURLEDSCREW

10–32 UNC–2B

.50

ø1.12

ø2.00

R.12

.20

1.50.06 X 45°CHAMFER

ø.50

ø.50

.25.88

ø.19

2X .03 X 45° CHAMFER

MEDIUM DIAMOND KNURL


10–32 UNC–2A X .50 LONG

You should now have three tabs at the bot-tom of the drawing area, one for each paper-space layout view and one for model space. Follow these steps to continue building the working drawing:

1. Pick the Model tab to return to the work-ing area of the drawing. All of the follow-ing steps should be done in model space.

2. Create the orthographic views (see Figure 13-23). Be sure to create the views at full size (scale of 1:1). Draw the views in the positions you want them to appear in the layout.

3. Move to another part of the drawing area, well away from the orthographic views, and create the assembly view. Because the orthographics have already been drawn, you can copy parts of them to use in the assembly drawing. For example, you can copy the beam, then delete the interior break, extend the lines to the full 8″, and move the ends to their new posi-tions. Copy the head and rotate the copy 180° to form the basis for the head in the

drawing. You will have to rearrange the internal details and reapply the hatch, but that is faster than starting from scratch. The scriber can be used without modifi cation. The screw can simply be copied, rotated, and placed as necessary.

4. Set up the orthographic layout view as in Figure 13-24. To do this, pick the Orthographics layout tab. Notice that the entire drawing appears on the layout sheet. To show only the ortho-graphic views, you will need to move them. To do this, pick the PAPER button at the bottom of the screen. The but-ton changes to MODEL, indicating that you are now in model space. This allows you to work directly with the objects you drew in model space. Use the PAN com-mand to move the entire drawing so that the orthographic views are centered on the sheet and the assembly drawing is hidden from view. If you need to move individual views, you can use MOVE or any other drawing command because

Figure 13-23

Draw the orthographic views in model space.


REVISIONS

ZONE REV DESCRIPTION DATE APPROVED

SIZE FSCM NO.

SCALE

DWG NO.

SHEET

REV

A1:1 1 OF 2

MARKING GAGE

1.00

.34

4 SCRIBER

.09

1 HEAD

10–32 UNC–2B

.50

ø1.12

ø2.00

R.12

.201.50

.06 X 45°CHAMFER

ø.50

10-32 UNC-28X .70

2 BEAM

8.00


.25

ø.50 .20

3 KNURLEDSCREW

ø.50

.25.88

ø.19

2X .03 X 45° CHAMFERMEDIUM DIAMOND KNURL


10–32 UNC–2A X .50 LONG

you are in model space, even though the border and title block are visible.

5. Pick the Assembly layout tab and repeat the procedure in step 4 to center the assembly view on the sheet, as shown in Figure 13-25. The orthographic views should not show on this sheet.

6. Fill in the title block with the appropriate information.

7. Generate the information for the bill of materials. By looking at the exploded assembly drawing in Figure 13-18, you can see that the completed assembly will need one head, one beam, two knurled screws, and one scriber. Create a block for each item, including the knurled screw if you did not create it earlier. Add invisible, vari-able attributes to each block as follows:

Attribute Tag Prompt DefaultMaterial What material? CRSNotes Add any notes:

(Note that you do not want to set a default for the Notes tag.) Explode each block on the screen, if necessary, and reblock to include the attributes. Refer to Chapter 11 for more information about adding text attributes to blocks.

8. Before you generate the actual bill of materials, notice that, although you need only two knurled screws to complete the assembly, the knurled screw block is used three times in the drawing. To avoid erro-neously including three screws in the bill of materials, explode one of the screws. To do this, pick the Explode button or

Figure 13-24

Position the drawing so that only the orthographic views appear on the drawing sheet.


REVISIONS

ZONE REV DESCRIPTION DATE APPROVED

SIZE FSCM NO.

SCALE

DWG NO.

SHEET

REV

A1:1 2 OF 2

MARKING GAGE

MARKING GAGE1

2

3

4

3

enter EXPLODE at the keyboard, and select one of the screws. When you explode a block, it loses its associated attributes.

9. Generate the bill of materials. (See the next section for details.)

10. Check the drawing.

Identify What command is used to center orthographic views on the layout sheet?

Generating the Bill of Materials AutoCAD and many other CAD programs

allow you to generate a bill of materials auto-matically based on the attributes associated

with blocks you have inserted into the drawing. The advantage of this method is its accuracy. Each time you insert a block, AutoCAD stores the attribute information in the drawing data-base. When you want to create the bill of mate-rials, you extract the attribute information.

Attribute ExtractionAutoCAD povides a wizard for extracting

the attributes from blocks in a drawing fi le. You can either create a table in the drawing to display the information or save the infor-mation to a spreadsheet document. Note that the wizard’s pages and appearance vary in dif-ferent AutoCAD versions. In general, follow these steps to extract the attributes from the marking gage drawing. Pick the Next bottom at the bottom of each page of the wizard to proceed to the next page.

Figure 13-25

The Assembly layout sheet.


Figure 13-26

Finished bill of materials for the marking gage

1. From the Tools pull-down menu, select Attribute Extraction to display the fi rst page of the Attribute Extraction wizard.

2. Pick the top radio button to create a table from scratch.

3. For the data source, choose to use the current drawing.

4. Choose the blocks you want to include and the attributes from those blocks that you want to extract.

5. Choose to extract the attributes to an AutoCAD table.

6. If your version of AutoCAD provides the options, enter Bill of Materials for the name of the table, and choose the default table style.

7. Choose Finish on the last page of the wizard and pick a point in the drawing to place the bill of materials.

8. Pick a point in the drawing fi le to place the completed bill of materials in the drawing (see Figure 13-26).

If you wish, you may add formatting to make the fi le more easily readable. For exam-ple, you may wish to make the BILL OF MATE-RIALS label and the column heads bold. To do this, simply double-click the text you want to change. The Text Formatting toolbar appears, allowing you to make changes to the font and appearance of the text.

Checking the DrawingWhen a drawing is fi nished, it must be

reviewed very carefully before it is used. This critical step is called checking the draw-ing. Though you should check all your drawings, it is important to have someone else check it, as well. A person who has not worked on the drawing will be better able to spot errors. A thorough check should follow a set order of procedures. See Appendix B for a checklist you can use to check any work-ing drawings.

Section 13.2 AssessmentAfter You Read

Self-Check 1. Outline the steps in creating a working

drawing using board or CAD techniques. 2. Explain how to create detail drawings,

assembly drawings, and assembly work-ing drawings.

3. Name the information that is includedin a bill of materials.

4. Explain the purpose for the bill of materials.

Academic IntegrationEnglish Language Arts

5. Thinking about the fact that all manu-factured items must be designed, write a one-page essay on the role of design/engineering businesses in the economy.

Drafting Practice 6. Prepare a detail drawing of the journal

bearing shown in Figure 13-1. Deter-mine an appropriate scale and dimen-sion the drawing.

Go to glencoe.com for this book’s OLC for help with this drafting practice.



Review and AssessmentChapter Summary

Section 13.1 The main types of working drawings are detail and assembly working drawings.The setup for a working drawing includes choosing the views and scale, grouping and placing parts, and adding the title block, revision block, bill of materials, and notes.

•

•

Section 13.2 Every working drawing has a title block located at the bottom border which includes important reference information about the drawing.Most working drawings include a bill of materials which can appear on the drawing sheet or as a separate attached document.A working drawing should always be carefully checked according to standard procedures.

•

•

•

13

Content Vocabularyworking drawing (p. 459)detail drawing (p. 459) combination drawing (p. 461)tabulated drawing (p. 462)

•••

•

assembly drawing (p. 462) assembly working drawing (p. 463) reference assembly drawing (p. 463) bill of materials (p. 467)

••

•

•

FAO (p. 468)multiple layouts (p. 473)

Academic Vocabularyassemble (p. 459)formats (p. 467)estimate (p. 470)

••

•••

Review Content and Academic Vocabulary 1. Use each of these content and academic vocabulary terms in a sentence or drawing.

Review Key Concepts2. List the types of working drawings discussed in this chapter. 3. Identify the parts of a working drawing layout.4. Contrast creating a working drawing with board techniques and CAD techniques. 5. Outline the steps for creating a detail working drawing. 6. Locate the two positions for placement of a title block. 7. Explain how to compile a bill of materials with board-drafting and CAD techniques.


True/False QuestionsDirections Read the following statements and determine whether each statement is true or false. 11. A pictorial drawing usually works best

as a detail drawing.TF

12. The primary characteristic of a per-son you would want to check your fi nished working drawing is speed.

TF

Technology 8. Understanding Communications

TechnologyCommunications technology is all around us

and is rapidly advancing. Using different sources for research, such as the Internet and technol-ogy magazines, identify in a two-page essay some recent advances in communications tech-nology. Outline the steps for how one advance led to another. Explain how you think commu-nications technology might advance in the near future. Give reasons for your predictions.

9. Communication SkillsYou have been asked to handle a request for

drawings by one of your fi rm’s overseas cli-ents. In meeting with their representative over the phone and in person, you fi nd communi-cation diffi cult because of his strong French accent. You realize that it is imperative to understand exactly what he needs. Brainstorm problem-solving techniques that might help you approach the situation in the best way.

Mathematics 10. Solving Word Problems

Igor is interested in getting a Master’s Degree in engineering, but he can only do so by tak-ing night classes since he has a full-time job. He has to complete 36 credits in all, and he can take only 3 credits per quarter. Since there are four quarters in a year, how long will it take?

Understanding Word ProblemsWhen a word problem involves multiple

steps, it is helpful to outline the information before you solve it.

Step 1: Make a list of the information you already have and the information you are inves-tigating, then decide how to use the informa-tion to solve the problem.

Step 2: Start working with the information to see what you come up with: 3 credits per quarter � 4 quarters per year � 12 credits per year. Is 36 divisble by 12? Solve.

Prep For

TEST-TAKING TIP

If each item on a test is worth the same number of points, do not spend too much time on questions that are confusing or that you are really uncertain about.

Win Competitive Events

13. Leadership CharacteristicsOrganizations such as SkillsUSA offer a

variety of architectural, career, and draft-ing competitions. Completing activities such as the one below will help you pre-pare for these events.

Activity Identify people you know or know about whom you consider to be leaders. Then list the characteristics these people share. Next write a 100-word para-graph explaining whether you agree with the statement “Good leaders are born, not made.” Explain the reasons for your position and give examples for support.

Go to glencoe.com for this book’s OLC for more information about competitive events.

Review and Assessment 481


T KEYWAY 188 WIDE X 09

O2.00

O2.00

O1.50

O1.25

O .625

.44

.50

1.38

.62

.31

.25

.25-20 UNC-2BASME B1.1

•

Problems13Drafting Problems

The drafting problems in this chapter are designed to be completed using board drafting techniques or CAD.

For problems 1 through 25, follow the instructions for each drawing prob-lem. Detrmine an approporate scale if the scale is not given, and dimension the drawings.

Figure 13-27

1. Make a working drawing of each part of the coupler shown in Figure 13-27. Ends: die-cast aluminum. Spacer: rubber.

2. Make an assembly drawing of the coupler shown in Figure 13-27. Estimate all sizes and details not given.


O.50

O.38025.38000

O.1207.1200

O.3805.3803

1.00

.25

.38

.75

.38

2.38

MEDIUMKNURL

.44

O.1207.1200

.03 X 45 CHAMFER°

3

2

4

1

O.12 X 6.00DRILL ROD

DEPTH ROD

KNURLED SCREW

.03 X 45 CHAMFER°

12–24 UNC–2AASME B1.1

3.00.25

.75

O.50

HANDLE

BASE

.62

MEDIUMKNURL

T

R4

0.8

22

0.8

R4

4

8

20

60

10

2 X 45°

M612 LONG

M512 LONG

O16

O9.5

O14

O8 X 600CRS ROD WITH5 WIDE FLAT

MEDIUMKNURL

MEDIUMKNURL

THREAD CONTROLLING ORGANIZATIONAND STANDARD–ASME B1.13M-2001

O2.5

O8

54

28

12

6

3. Make a working drawing of each part of the depth gage shown in Figure 13-28. All parts: cold-rolled steel.

4. Make an assembly drawing of the depth gage shown in Figure 13-28. Estimate all sizes and details not given.

Figure 13-28

5. Make a working drawing of each part of the trammel shown in Figure 13-29. Specify “2 REQD” for the point, body, and knurled screw. The point is to be heat-treated after machining.

6. Make an assembly drawing of the tram-mel shown in Figure 13-29. Estimate all sizes and details not given.

Figure 13-29

METRIC

Problems 483

1.50O

5.00O1.20O

2.00O

5.001.25

OT

.50-20 UNF-3A X 2.00 LONG

.03 X 45° CHAMFERBOTH SIDES

DRILL AND TAPFOR 12-28 NFSET SCR


4.00

1.50

.50

.03 X 45° CHAMFER

.31

.88

.02.12

.25

•

Problems13

7. Make a working drawing of each part of the arbor shown in Figure 13-30. Flanges: die-cast aluminum. Shaft: cold-rolled steel.

Figure 13-30

8. Make an assembly drawing of the arbor shown in Figure 13-30 with a Ø6.00 �1.00 grinding wheel between the fl anges. Show sectional views where practical. Draw all fasteners. Estimate all sizes and details not given.


.07

.18

40°

SECTION A–A

70°

65°

1.25

VIEW "A"

1.38

VIEW “A”

.25 TWIST DRILL

.62

2X.06 X 45

.25

.18 .56

12–28 NF FOR.25 LONG SET SCREW


O

A

A

°

9. Making a working drawing of each part of the power expansion bit shown in Figure 13-31. Cutter: tool steel. Body: cast iron. Use sectional views where necessary.

Figure 13-31

10. Make an assembly drawing of the power expansion bit shown in Figure 13-31. Estimate all sizes and details not given.

Problems 485

1.003.00

.62

.06R.12

DRILL AND COUNTERSINKFOR 6–32 UNC X .25 LONGFLAT HEAD MACHINE SCREWS

.25 X 1.75 LEVEL GLASS TOBE ATTACHED WITH LATEXCALK. STRIPES TO BEADDED AFTER ASSEMBLY

O9.00

3.002.62

2.25R.56 .38

.62

.10

.12

.12

R.38

1.12

.06 .62

R.12

.75

.25

3.00

Problems13

11. Make a working drawing of each part of the level shown in Figure 13-32, except do not draw the level glass. Body: die-cast aluminum. Top plate: cold-rolled steel. Use sectional views where neces-sary. Fillets � 1/8 R.

Figure 13-32

12. Make an assembly drawing of the level shown in Figure 13-32. Redesign the level to include vertical and 45° angle level glasses if desired. Estimate all sizes and details not given.


1.00

.50

3.75

1.38.88

.5004

.5000

.49975

.49945

.25-20 UNC-3B FOR SET SCREW

NOTE: ALL CHAMFERS .03 X 45°

.25 SQ X 2.25CUTTER BIT TOBE SHARPENEDAS DESIRED

.50.12

.12

.80

4.75

3.25

.25 SQ HOLETHROUGH

SLOT .16 WIDE X .04 DP


.25-20 UNC-3B FORSET SCREW

.25.50

Ø.75

.25 X 1.75 LONGTWIST DRILL

O

.62OO

O

O

O

13. Make a working drawing of each part of the circle cutter shown in Figure 13-33. Cutter: tool steel. Body and tool holder: cold-rolled steel.

Figure 13-33

14. Make an assembly drawing of the circle cutter shown in Figure 13-33. Show sectional views where necessary. Draw all fasteners. Estimate all sizes and details not given.

Problems 487

5

16

114

38

14

141

38

38

6

1 34 DIA

DRILL, DEEP

10 DIA X THICK

2 DIA, 5 HOLES

3414

1

DRILL 12

9 DIA X THICK DRILL, 5 HOLESEQUALLY SPACED

6

3

1

18

X 45 CHAMFER °

1

2

1

2

7

8

1

2

1

2

3

4

3

8

3

8

5

16

5

8

7

8

Problems13

15. Make detail working drawings of each part of the beverage server shown in Figure 13-34. Material: hardwood.

Figure 13-34

17. Make a complete bill of materials for the beverage server shown in Figure 13-34. Based on the bill of materials, estimate the cost to manufacture the server, and prepare an estimated budget.

16. Make an assembly drawing of the bever-age server shown in Figure 13-34.


2.75

.40 .010+_

.12 X 45°BOTH SIDES

.06 X 45°BOTH SIDES

.137

.132.137.132

4.3224.312

SECTION A-A

SECTION B-B

1.75

R.38

10°

.12-27 NPT, ASME B1.20.1ONE END ONLY

R.80

R.90

3.00

3.00

2.80

7.44

7.50

3.50

R.25

R.12.25

1.75

1.25

8.25

ROUNDS .12FILLETS R.25

45°

45°7.00

1.75

1.75

1.06

1.061.75

5.12

.25

4.1254.126

R2.50

R1.38

B

B

A

A.62

O

O

O

O O

2.75

.25

1.9331.931

CL

CL

4.62

432

128

42

64 29

58

436

12076

76

16120

104 104 22

18

R68

74METRIC

18. Make a working drawing of the housing shown in Figure 13-35. Use partial and sectional views where needed. Material: cast iron. Estimate all sizes not given.

Figure 13-35

19. Make detail working drawings of each part of the hung bearing shown in Figure 13-36. Fully dimension each part. All bolts are 16 mm in diameter. Do not draw bolts and nuts. Estimate sizes not given.

Figure 13-36

Problems 489

0

"X"

R6

R6

38

8

20 24

A

A

12

22

100

8

88

8

10

SECTION A–A

8

VIEW "X"

2

12

45°

58 32

0

M12, ASME B1.13M

R6

2410

2222

250

188

6

R14

METRIC

Problems13

20. Make a working drawing of the end base shown in Figure 13-37. Use partial and sectional views where needed. Material: cast iron. Estimate all sizes not given.

Figure 13-37


O1.38O1.00

O2.38

.12O.31 RIVETS, 6 REQDEQUALLY SPACED

.70

.50

O3.50O4.75

.25

.75

3.00.88

1.50

O1.25O2.12

O2.25

O5.00

O6.62

O8.00

.20 O.25 .31

.25

30

O1.88

1.00–16 UN

OILLESS BUSHING

O.120 °

PEEN OVER ENDAT ASSEMBLY

O4 X 38COTTER PIN2 REQUIRED O110 O58

O82O25

O38

O44

R55

120

44 32

11058

R50

R50 12

R6

R4430

R26 R32

R6

12RADIUS TO SUIT

11 50

86

11

10442

92

O28

R4R44

R20R15

80

R4R3

O26

R6

9.5

R24

R60

42

11

R3

METRIC

21. Make a front view and section of the cushion wheel shown in Figure 13-38at full size. This type of wheel is used on warehouse or platform trucks to reduce noise and vibration.

23. Make detail drawings of the crane hook parts shown in Figure 13-39.

Figure 13-38

Figure 13-39

22. Make a complete set of detail drawings, full size, with a bill of materials, for the cush-ion wheel shown in Figure 13-38. Three sheets will be needed. Rivets are purchased and therefore need not be detailed, but they should be listed in the bill of materials.

Problems 491

WOODRUFF KEY #809

3 RIBS EQ SPACED.31 THICK

.12 NPT, ASME 1.20.1 1.00–16 UN–3A, ASME B1.1

.06.56

1.501.38

.38

.31

5.00

5.30

3.56

18.75

1.75

R.50

.50

R1.62

.50.88

R.38

13.75R.62.50

O6.25

O1.00

O8.00

O1.75

O5.00

O1.38

O4.38

O2.75

O1.12

O2.12

30°

.12R.25

R.25.69

.50+

.12 NPT

O.405

O.50 X 2 HEX HDCAP SCREW4 REQUIRED

1.12

SPLINE–.31 WIDE X .22T

CUTTER

RADIUS

BILL OF MATERIAL FOR UNIVERSAL JOINT NO. NAME QTY MATL NOTES

1 FORK 2 C12 RING 1 STEEL3 STUD 4 STEEL4 NO. 4 TAPER PIN 2 PURCHASED

O

M123 WIDE X 1.6

THREAD CONTROLLING ORGANIZATIONAND STANDARD–ASME B1.13M-2001

T

3

14

6 10

O8

3

3

27

2

1

41

14

M12 X 1.25

NO. 4 TAPER PINDRILL AND REAMIN POSITION

R16 3.232

10

60

24R12

19

R 24

R10

O19O36

66 38

60

20

O8

O19

38

38O44

Problems13

24. Make detail drawings of the base, pulley, bush-ing, and shaft shown in Figure 13-40. Include a bill of materials for the complete pulley-and-stand unit. Scale: Full size. Use three sheets. Top view may be drawn as a half-plan view.

Figure 13-40

25. Make a two-view assembly drawing in section of the universal joint shown in Figure 13-41.

Figure 13-41

METRIC


Metric

1. Design a collapsible sawhorse. Height is 560 mm. Length is 800 mm. Make a set of working drawings, a bill of materials, and an assembly drawing. Material optional.

Teamwork

2. Design a series of tool holders for use in a home workshop. Begin by developing a list of tools you would expect to fi nd in a home workshop. Divide the list among the team members. Each team member is responsible for preparing working draw-ings for each holder on his or her list. Prepare design sketches for team review. Material optional.

Teamwork

3. Design a portable, collapsible stadium seat. Begin with design sketches. Consider fac-tors such as weight and cost of materials. How can you minimize costs while pro-viding all of the required features? Prepare assembly working drawings with a materi-als list. Other design considerations:

Add storage for a rain poncho. Add a removable cup holder. Create a bill of materials for the stadium seat. Estimate the cost to produce the seat, and prepare a budget. (Hint: Remem-ber to include any sales tax in the cost of materials so that your budget will not be underfunded.)

If time allows, form a student business to market the stadium seat.

•••

•

4. In the real world, companies must do more than just create comprehensive working drawings for their products. To sell the products, they must bid on suit-able jobs and bill the client for the work performed. Research and analyze the bid-ding and billing structures used by design and engineering fi rms. Then choose at least two of the products for which you have created working drawings in this chapter. Write a report explaining which bidding structure and which billing struc-ture would be most appropriate for a com-pany that makes these products, and why.

5. CAD solid models are frequently used to drive manufacturing processes directly. To be used this way, the models must be extremely accurate. One error that can shut down a manufacturing process completely is a gap between surfaces in the model. In most cases, this costly error can be avoided by careful modeling. However, gaps may still occur occasionally, often due to incor-rectly performed alterations to the origi-nal model. Some CAD software provides a query function to check for the existence of such surface-to-surface gaps. Other soft-ware, including AutoCAD, requires you to zoom in to view each intersection at close range. Choose three solid models that you have created in this book. Zoom in on all of the surface-to-surface and point-to-point intersections to see whether they meet exactly. If your software is capable of checking for gaps automatically, perform the appropriate query functions. List any gaps you fi nd in your models. Explain why the gaps occurred. What caused them? Then fi x the gaps and resave the fi les.

Design ProblemsDesign problems have been prepared to challenge individual students or

teams of students. In these problems, you are to apply skills learned mainly in this chapter but also in other chapters throughout the text. They are designed to be completed using board drafting, CAD, or a combination of the two. Be creative and have fun!

Problems 493

13 working drawings - typepadnorthcobbhs.blogs.com/files/ch_13.pdf · preview working drawings give...

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