Chapter 2 - Dimensioning - EGE4

8/20/2019 Chapter 2 - Dimensioning - EGE4

1/162

Copyright©2010 by K. Plantenberg

Restricted use only

Chapter 2:

Dimensioning

Basic Topics

Advanced Topics

Exercises


2/162


Restricted use only

Dimensioning: Basic Topics

Summary2-1) Detaied Dra!ings

2-2) "earning to Dimension

2-#) Dimension Appearance and Techni$ues%2-&) Dimensioning and "ocating Simpe

'eatures%

2-() Dimension Choice%


3/162


Restricted use only

Dimensioning: Advanced Topics

2-) Dimensioning and "ocating Advanced'eatures%


4/162


Restricted use only

Dimensioning: Exercises

Exercise 2-1: Dimension typeExercise 2-2: Spacing and reada*iity 1

Exercise 2-#: Spacing and reada*iity 2

Exercise 2-&: Dupicate dimensions

Exercise 2-: Dimension pacement

Exercise 2-(: Circuar and rectanguar vie!s

Exercise 2-+: Dimensioning and ocating

,eaturesExercise 2-: Advanced ,eatures

Exercise 2-.: Dimension accuracy

Exercise 2-1/: 0ound o,,


5/162


Restricted use only

Dimensioning: Exercises

Exercise 2-11: Dimension choiceExercise 2-1&: Dimensioning 1

Exercise 2-1: Dimensioning 2

Exercise 2-1(: Dimensioning #

Exercise 2-1+: Dimensioning &


6/162


Restricted use only

Dimensioning

Summary


7/162Copyright©2010 by K. Plantenberg

Restricted use only

Dimensioning Summary

hat !i !e earn in Chapter 2→ How to dimension an orthographic

projection using proper dimensioning

techniues.

3ey points

→ !imensions a""ect how a part is

manu"actured.



Restricted use only

Dimensioning

2-1) Detaied Dra!ings



Restricted use only

Detaied Dra!ings

4rthographic 5ro6ection: # shapedescription o" an object $"ront% top% right

side &iews'.

Detaied Dra!ing: #n orthographic

projection% complete with all the

dimensions and speci"ications needed tomanu"acture the object.



Restricted use only

Detaied Dra!ing Exampe


11/162


Restricted use only

Detaied Dra!ings

(hould we dimension an object using thedimensions that we used to draw the

object)

*o

+hese are not necessarily the same

dimensions reuired to manu"acture it.

,e need to "ollow accepted standards.

$#(- /1. 133'


12/162


Restricted use only

Dimensioning

2-2) "earning To Dimension


13/162


Restricted use only

"earning to Dimension

hat is our goa !hen dimensioning apart

→ 4asically% dimensions should be gi&en in a

clear and concise manner and shouldinclude e&erything needed to manu"acture

and inspect the part e5actly as intended by

the designer.


14/162


Restricted use only


5roper dimensioning techni$uesre$uire the 7no!edge o, the ,oo!ing

three areas%

→ !imension #ppearance6+echniue→ !imensioning and 7ocating 8eatures

→ !imension Choice


15/162


Restricted use only

Dimensioning

2-#) Dimension Appearance

and Techni$ues


16/162


Restricted use only


Dimension Appearance8Techni$ue:!imensions use special lines% arrows%

symbols and te5t.

a' +he lines used in dimensioning.

b' +ypes o" dimensions.

c' !imension symbols.d' !imension spacing and readability.

e' !imension placement.


17/162


Restricted use only

"ines used in Dimensioning

Dimensioning re$uires the use o,→ !imension lines

→ 5tension lines

→ 7eader lines

#ll three line types are drawn thin so that

they will not be con"used with &isible lines.


18/162


Restricted use only

Dimension "ine

Dimension ine: # line terminated byarrowheads% which indicates the direction

and e5tent o" a dimension.


19/162


Restricted use only

Dimension "ine

Dimension ine: 9deally% the dimensionline is bro:en to allow "or the insertion o"

the "eature;s si


20/162


Restricted use only

Extension "ine

Extension ine: #n e5tension line is athin solid line that e5tends "rom a point on

the drawing to which the dimension re"ers.

7ong e5tensionlines should be

a&oided.


21/162


Restricted use only

"eader "ine

"eader "ine: # straight inclined thin solidline leading to a note or dimension &alue.


22/162


Restricted use only

"eader "ine

"eaders may *e terminated:→ with an arrow% i" it ends on the outline o" an

object.


23/162


Restricted use only

"eader "ine

"eaders may *e terminated:→ with a dot or nothing i" it ends within the

outline o" an object.


24/162


Restricted use only

"eader "ine

Avoid9→ Crossing leaders.

→ 7ong leaders.

→ 7eaders that are parallel to adjacentdimension% e5tension or section lines.

→ (mall angles between the leader and the

terminating sur"ace.


25/162


Restricted use only

Arro!heads

#rrowheads are drawn between thee5tension lines i" possible. 9" space is

limited% they may be drawn on the outside.


26/162


Restricted use only

Types o, Dimensions

Dimensions are given in the ,orm o,linear distances angles and notes%

→ 7inear distances= +hey are usually arrangedhori


27/162


Restricted use only

Types o, Dimensions


→ #ngles= >sed to gi&e the angle betweentwo sur"aces or "eatures o" a part.


28/162


Restricted use only

Types o, Dimensions


→ *otes= >sed to dimension diameters% radii%cham"ers% threads% and other "eatures that

can not be dimensioned by the other two

methods.


29/162


Restricted use only

Exercise 2-1

Dimension types


30/162


Restricted use only

Exercise 2-1

Count the di""erent types o" dimensions.→ How many linear hori


31/162


Restricted use only

Exercise 2-1

Count the di""erent types o" dimensions.→ How many linear &ertical dimensions are

there) ?


32/162


Restricted use only

Exercise 2-1

Count the di""erent types o" dimensions.→ How many angular dimensions are there) 1


33/162


Restricted use only

Exercise 2-1

Count the di""erent types o" dimensions.→ How many leader line notes are there) 1


34/162


Restricted use only

"ettering

"ettering shoud *e egi*e easy toread and uni,orm throughout the

dra!ing%

→ ;pper case letters should be used "or alllettering unless a lower case is reuired.

→ +he minimum lettering height is 0.12 in $?

mm'.


35/162


Restricted use only

Dimensioning Sym*os

Dimensioning sym*os repace text%→ +he goal o" using dimensioning symbols is to

eliminate the need "or language translation.

hy is it important to use sym*os%

→ How many products are designed in the

>nited (tates)

→ How many products are manu"actured or

assembled in the >nited (tates)


36/162


Restricted use only

Dimensioning Sym*os

Term Sym*o!iameter n

(pherical diameter (n

Radius R(pherical radius (R

Re"erence dimension $@'

Counterbore 6 (pot"ace vCountersin: w

*umber o" times or places A


37/162


Restricted use only

Dimensioning Sym*os

Term Sym*o!epth 6 !eep x

!imension not to scale 10

(uare $(hape' o #rc length

Conical +aper y

(lope z(ymmetry i

1


38/162


Restricted use only

Spacing and 0eada*iity

Dimensions shoud *e easy to readand minimi


39/162


Restricted use only


a' +he spacing between dimension linesshould be uni"orm throughout the

drawing.

b' !o not dimension inside an object or

ha&e the dimension line touch the object

unless clearness is gained.


40/162


Restricted use only


c' !imension te5t should be hori


41/162


Restricted use only

Exercise 2-2

Spacing and 0eada*iity 1


42/162


Restricted use only

Exercise 2-2

7ist the dimensioning mista:es and thendimension the object correctly.

h t th t " di i i i t : )


43/162


Restricted use only

hat are the types o" dimensioning mista:es)


44/162


Restricted use only

1' (pacing

' -issing dim.

$n o" hole'

?' +e5t

' *o Bap

2' !on;t dim. inside the object.

Correctly !imensioned


45/162


Restricted use only



46/162


Restricted use only


e' !imension lines should not crosse5tension lines or other dimension lines.

→ 5tension lines can cross other e5tension

lines or &isible lines.

"' 5tension lines and centerlines should

not connect between &iews.


47/162


Restricted use only


g' 7eader lines should be straight% notcur&ed% and point to the center o" the arc

or circle at an angle between ?0o 0o.


48/162


Restricted use only

Exercise 2-#

Spacing and 0eada*iity 2


49/162


Restricted use only

Exercise 2-#

7ist the dimensioning mista:es and thendimension the object correctly.



50/162


Restricted use only



51/162


Restricted use only

?' +e5t

2' Center line

' Crossing dim.

and e5t. line

1' 7eader line



52/162


Restricted use only



53/162


Restricted use only


h' !imensions should not be duplicated orthe same in"ormation gi&en in two

di""erent ways.

→ 9" a re"erence dimension is used% the si


54/162


Restricted use only

Exercise 2-&

Dupicate dimensions


55/162


Restricted use only

Exercise 2-&

8ind theduplicate

dimensions and

cross out theones that you

"eel should be

omitted.


56/162


Restricted use only

Are there any duplicatesin this group?Which oneshouldbe omitted?


57/162


Restricted use only

Are there any duplicates

in this group?

Which ones

shouldbe omitted?


58/162


Restricted use only

Are there any duplicatesin this group?Which oneshouldbe omitted?


59/162


Restricted use only

Dimension 5acement

Dimensions shoud *e paced in such a!ay as to enhance the communication

o, your design%


60/162


Restricted use only

Dimension 5acement

a' !imensions should be groupedwhene&er possible.

b' !imensions should be placed between&iews% unless clearness is promoted by

placing some outside.


61/162


Restricted use only

Dimension 5acement

c' !imensions should be attached to the&iew where the shape is shown best.

d' !o not dimension hidden lines.


62/162


Restricted use only

Exercise 2-

Dimension pacement


63/162


Restricted use only

Exercise 2-

7ist thedimensioning

mista:es and

thendimension the

object

correctly.


64/162


Restricted use only

,hat are the

types o"

dimensioningmista:es)

1' 4etween &iews


65/162


Restricted use only

1' 4etween &iews

2' 7eaders"loat up

?' !on;t dim.

Hidden lines

' !im where

"eature is

shown best

' 7ong

e5t. line

' Broup



66/162


Restricted use only



67/162


Restricted use only

Dimensioning

2-&) Dimensioning and

"ocating Simpe 'eatures


68/162


Restricted use only


Dimensioning and "ocating 'eatures:!i""erent types o" "eatures reuire uniue

methods o" dimensioning.


69/162


Restricted use only

Dimensioning 'eatures

a' # circle is dimensioned by its diameterand an arc by its radius using a leader

line and a note.


70/162


Restricted use only

Exercise 2-(

Circuar and rectanguar vie!s


71/162


Restricted use only

Exercise 2-(

#nswer uestionsabout the cylindrical

and hole "eatures o"

the part shown.

8ind the hole and


72/162


Restricted use only

8ind the hole and

cylinder.

,hich &iew is

considered the circular

&iew and which is

considered therectangular &iew)

Circular &iew

Rectangular &iew

7oo:ing at just the


73/162


Restricted use only

7oo:ing at just the

top &iew% can you

tell the di""erence

between the hole

and the cylinder)

*o


74/162


Restricted use only

(o that the cylinder

is not con"used with

a hole.

,hy is the diameter

o" the hole gi&en in

the circular &iew anddiameter o" the

cylinder gi&en in the

rectangular &iew)


75/162


Restricted use only


b' Holes aredimensioned by

gi&ing their

diameter and

location in the

circular &iew.

Di i i ' t


76/162


Restricted use only


c' # cylinder isdimensioned by

gi&ing its

diameter and

length in the

rectangular &iew%

and is located in

the circular &iew.

Di i i ' t


77/162


Restricted use only


d' +he depth o" a blind hole may bespeci"ied in a note and is the depth o" the

"ull diameter "rom the sur"ace o" the

object.

Di i i ' t


78/162


Restricted use only


e' 9" a hole goes completely through the"eature and it is not clearly shown on the

drawing% the abbre&iation D+HR>E "ollows

the dimension.

Di i i ' t


79/162


Restricted use only


"' 9" a dimension is gi&en to the center o" aradius% a small cross is drawn at the

center.

Di i i ' t


80/162


Restricted use only


"' ,here the center location o" the radius isunimportant% the drawing must clearly

show that the arc location is controlled

by other dimensioned "eatures such as

tangent sur"aces.

Di i i ' t


81/162


Restricted use only


g' # complete sphere is dimensioned by itsdiameter and an incomplete sphere by

its radius.

Di i i ' t


82/162


Restricted use only


h' Repetiti&e "eatures or dimensions maybe speci"ied by using the symbol DAE

along with the number o" times the

"eature is repeated.

→ +here is no space between the number o"

times the "eature is repeated and the DAE

symbol% howe&er% there is a space between

the symbol DAE and the dimension.


83/162


Restricted use only

Exercise 2-+

Dimensioning and ocating

,eatures

E i 2 +


84/162


Restricted use only

Exercise 2-+

Dimension the o*6ect sho!n%

ow do we dimension the hole diameters)


85/162

Copyright©2010 by K. PlantenbergRestricted use only

ow do we locate the holes)


86/162


ow do we dimension the cylinder diameters)


87/162


ow do we dimension the cylinder heights)


88/162


ompletely dimensioned.


89/162


(:ip ad&anced topic


90/162


Dimensioning

2-) Dimensioning and

"ocating Advanced 'eatures



91/162



a' 9" space is ata minimum%

the si


92/162



*) Soid parts !ith rounded ends→ Bi&e the o&erall dimension.

→ Partially rounded ends= radii are also gi&en.

→ 8ully rounded ends= radii are indicated but

the &alue is not gi&en.



93/162



c) Sots→ F&erall

dimension% or

dimension

betweencenters.

→ F&erall width.

→

+he radii areindicated but the

&alue is not

gi&en.



94/162



d' +he length o" an arc is dimensionedusing the arc length symbol%



95/162



e) E$uay spaced ,eatures

G o" spaces

(pace dim

+otal distance

Re"erence



96/162



e) E$uay spaced ,eatures



97/162



"' 9" a part is symmetric% it is only necessaryto dimension to one side o" the center

line o" symmetry.



98/162



g' Counterbored holes !rill !9#

C;4ore !9#

C;4ore depth



99/162



g' 9" the thic:ness o" the material below thecounterbore is signi"icant% this thic:ness

rather than the counterbore depth is

gi&en.

Appication =uestion 2-1


100/162



,hat do you thin: a counterbored hole isused "or)



101/162



h' (pot"aced Holes= +he di""erencebetween a C;4FR and a (pot"ace is

that the machining operation occurs on a

cur&ed sur"ace.

*otice that the

depth can not

be speci"ied in

the note.



102/162



i' Countersun: Holes!rill !9#

!rill !epth

C;(in: !9#

C;(in: angle

(pace



103/162



,hat do you thin: a countersun: hole isused "or)



104/162



j' Cham"ers= !imensioned by a lineardimension and an angle% or by two linear

dimensions.



105/162



j' Cham"ers= !imensioned by a lineardimension and an angle% or by two linear

dimensions.

(pace

Appication =uestion 2-#


106/162


Appication =uestion 2 #

,hat do you thin: a cham"er is used "or)

(a"ety.

9mpro&e engagement o" mating parts.

Dra!ing >otes


107/162


Dra!ing >otes

Dra!ing notes give additionain,ormation that is used to compement

conventiona dimension%

→ manu"acturing reuirements

→ treatments and "inishes

→ blan:et dimensions $e.g. si


108/162


Exercise 2-

Advanced ,eatures

Exercise 2-


109/162


Exercise 2

7ist thedimensioning

mista:es and

then

dimension

the object

correctly.


110/162


,hat are the types

o" dimensioning

mista:es)

1' >se

symbols


111/162


symbols

2' (paces?' #ngle up' Radius

' 7ocate radius center

' !on;t

dim.

hidden

"eatures

' !im. where

"eatures is

shown best

orrectly

imensioned


112/162


imensioned


113/162


Dimensioning

2-() Dimension Choice



114/162



Dimension Choice: /our choice o"dimensions will directly in"luence the

method used to manu"acture the part.

a' >nits and decimal places.

b' 7ocating "eature using datums.

c' !imension accuracy and error build up.

Dimension Choice


115/162


Dimension Choice

Dimension pacement and dimensiontext in,uences the manu,acturing

process used to ma7e the part%

→ -anu"acturing process should not be

speci"ically stated on the drawing.

Choose dimensions *ased on ,unction

,irst then manu,acturing%

;nits and Decima 5aces


116/162



a) Decima dimensions should be used "orall machining dimensions.

→ /ou may encounter a drawing that speci"ies

standard drills% broaches% and the li:e by

si


117/162



b' Fn drawings where all the dimensionsare either in inches or millimeters the

"ollowing note should be used.

→ >*7(( F+HR,9( (PC989!% #77

!9-*(9F* #R 9* -9779-+R( $or

9*CH('



118/162


b' 9" an inch dimension is gi&en on amillimeter drawing or &isa &ersa% the

abbre&iations > or mm should be

placed a"ter the dimension &alue.



119/162


c' -etric dimensions are gi&en in Imm; andto 0 or 1 decimal place $e.g. 10% 10.2'.

→ ,hen the dimension is less than a

millimeter% a


120/162


d' nglish dimensions are gi&en in Iinches;and to 2 decimal places $e.g. 1.2'.

→ #


121/162


e' -etric ?rd angle drawings aredesignated by the (9 symbol.

"ocating 'eatures ;sing Datums


122/162


g g

Consider three mutuay perpendicuardatum panes%

→ +hese planes are imaginary and

theoretically e5act.



123/162


g g

>o! consider a part that touches athree datum panes%

→ +he sur"aces o" the part that touch the

datum planes are called datum features.



124/162


g g

ost o, the time ,eatures on a part areocated !ith respect to a datum

,eature%



125/162


g g



126/162


g g

o! do !e choose !hich sur,ace !i*e a datum ,eature

ood datum ,eatures are:→ "unctionally important sur"aces→ mating sur"aces

→ big enough to permit its use in

manu"acturing the part



127/162


g g

9n a class setting% do we always :now the"unction o" the part)

No

We need to make an educated guess as to the

function of the part.



128/162


g g

a' !atum dimensioning is pre"erred o&ercontinuous dimensioning.



129/162


g g

b' !imensions should be gi&en betweenpoints or sur"aces that ha&e a "unctional

relation to each other

→ (lots% mating hole patterns% etc...

Appication =uestion 2-&


130/162

Copyright©

2010 by K. PlantenbergRestricted use only

hy is the distance *et!een the t!ohoes ,unctionay important

9" the hole pattern

mates with 2 pins or

bolts% the distance

between the holes is

more important thanthe distance "rom

the edge to the

second hole.

Dimension Accuracy


131/162

Copyright©


There is no such thing as an exactmeasurement%

→ &ery dimension has an implied or stated

tolerance associated with it.

→ # tolerance is the amount a dimension isallowed to &ary.


133/162

Copyright©


hich dimensions have impiedtoerances and !hich have stated

toerances

9mplied (tated9mplied

Exercise 2-.


135/162

Copyright©


rite do!n the range in !hich thedimension vaues are ao!ed to vary%

J 0.

1.

J 0.3

1.0

0.333

1.001

0ounding 4,,


136/162

Copyright©


The more accurate the dimension the

more expensive it is to manu,acture%

→ +o cut costs it is necessary to round o""

"ractional dimensions.

0ounding 4,,


137/162

Copyright©


o! do !e round o,,

→ 7et;s round o"" to the second decimal place.

1.12

2nd decimal place ?rd decimal place

0ounding 4,,


138/162

Copyright©


, the third decima pace num*er is:

→ less than % we truncate a"ter the second

decimal place.

1.12? 1.12

0ounding 4,,


139/162

Copyright©



→ greater than % we round up and increase

the second decimal place number by 1.

1.12 1.1?

0ounding 4,,


140/162

Copyright©



→ e5actly % whether or not we round up

depends on i" the second decimal place

number is odd or e&en. 9" it is odd% we

round up and i" it is e&en% it is :ept thesame.

1.1 1.1

1.1? 1.1


141/162


Restricted use only

Exercise 2-1/

0ounding 4,,

Exercise 2-1/


142/162


Restricted use only

0ound o,, the ,oo!ing ,ractions to

t!o decima paces according to the

rues stated a*ove%

(5/16) .3125→

(5/32) .1562 →

(1/) .125 →

(3/) .3!5 →

.31

.16

.12

.3

Cumuative Toerances


143/162


Restricted use only

Continuous dimensioning has the

disadvantage o, accumuating error%

→ 9t is pre"erable to use datum dimensioning to

reduce error buildup.

Cumuative Toerances


144/162


Restricted use only

hat is error *uid up

→ e L indi&idual dimension error

5.e ?5.e

5.e M 5.e M 5.e L ?5.3e


145/162


Restricted use only

Exercise 2-11

Dimension Choice

Exercise 2-11


146/162


Restricted use only

7ist the dimensioning mista:es and then

dimension the object correctly.

,hat are the dimensioning mista:es)


147/162


Restricted use only

1 N 2' 2 decimal places 6 *o leading


148/162


Restricted use only

' (ymbol' !ecimal

?' >se datum dimensioning

' !on;t dim. hidden "eatures



149/162


Restricted use only


150/162


Restricted use only

Exercise 2-1&

Dimensioning 1

Exercise 2-1&


151/162


Restricted use only

!imension

the "ollowing

object using

proper

dimensioningtechniues.

*otice the


152/162


Restricted use only

!id we need the

right side &iew)

datum "eatures

that were used.


153/162


Restricted use only

Exercise 2-1

Dimensioning 2

Exercise 2-1


154/162


Restricted use only

!imension the "ollowing object using

proper dimensioning techniues.


155/162


Restricted use only


156/162


Restricted use only

Exercise 2-1(

Dimensioning #

Exercise 2-1(


157/162


Restricted use only

!imension the "ollowing object using

proper dimensioning techniues.


158/162


Restricted use only


159/162


Restricted use only

Exercise 2-1+

Dimensioning &

Exercise 2-1+


160/162


Restricted use only

!imension

the "ollowing

object using

proper

dimensioningtechniues.


161/162


Restricted use only


162/162

Dimensioning

The End

Chapter 2 - Dimensioning - EGE4

Documents

Transcript of Chapter 2 - Dimensioning - EGE4