1. Model Documentation

2. Working Drawing Documentation
Once a design has been researched and approved, the part is sent to be prototyped or manufactured. Appropriate documentation is needed to communicate the idea to everyone in the company. This is the most difficult, time consuming, yet the most important part of engineering communication. These documentation are called working drawings.

3. What are Working Drawings?
Working drawings are a complete set of documents that specify how an object will be manufactured and assembled. Each set should include:
Part Drawings
Assembly Drawings
Parts List
Any Special Specifications or Instructions.

4. Working Drawings Elements of Working Drawings Drawing Layout
Drawing Views
Dimensioning
Annotations
Multiple Features

5. Drawing Layout Elements of Drawing Layout Sheet Styles and Sizes
Borders
Title Block
Scale
Revision Block

6. American National Standards Institute
Sheet Sizes
American National Standards Institute
ANSI

7. Title Block A box found in the lower right hand corner of a drawing.
It contains pertinent information on the part
Drawing Number
Scale
Material
Title or Description
Company
Tolerances

8. Title Blocks Zoning is used to find specific locations on the
drawing. Usually shown in numbers and letters.
General notes and information. Located here
you will see information on, fillet and rounds,
tolerances, and other general information that
would take up too much space on the drawing if
repeated on every feature.
Title of the project. As opposed to a
specific part.
Remember working drawings are made of many
different types of drawings and there are usually
more than one sheet that goes with a design.
ANSI Large style title block. All
title blocks should include the following
information.
Name of person who checked the drawing. Just
like first drafts of papers written in English class,
drawings go through many revisions.
Scale of the part is important so the person
being communicated to can get an idea of what
the part looks like.
Size of sheet. Very valuable when printing.
Another person will check the drawing and
approve the part for manufacture.
Company name. Many times companies will
create their own borders and their logo will
appear also.
Name of person who did the drawing.
Specific part name in relationship to the
total design.
Documentation of how many times the drawing
has been changed.

9. Scale
When objects can be drawn using the actual dimensions, it is referred to as full scale or 1:1. Some objects are drawn larger than actual size, so one can clearly see details and dimensions these can be as large as 10:1.
Scale is represented as an equation. The left side is the drawing size and the right side represents the part.

10. Scale
The bolt is drawn five times
larger than actual size
Scale 5:1

11. Drawing Views
For clear and accurate dimensioning and specification of a part the drawing may need a variety of views.
The five basic views are:
Orthographic
Isometric
Section
Auxiliary
Assembly

12. Orthographic (Multiview Drawings)
Orthographic Projection is also known as a Multiview drawing. Orthographic projection is a way to project a view based on a line of sight that is perpendicular to that view. There are six views to any object as shown in the next slide.

13. Orthographic (Multiview Drawings)
The arrows represent the
line of sight associated
with each view.

14. Orthographic Principal Views
Note how the views
are oriented. Each view is
adjacent to the other as
if they were unfolded
from a 3D shape.
Front,
Top and Right views
are used most often. You can
see how other views resemble
these three except they are not
as clear due to hidden lines.

15. Orthographic Angle of Projection
The example you have just seen is shown in the third angle of projection. This is the standard in the United States and Canada.

16. Orthographic 3rd Angle Projection
Views are projected onto planes
that exist on the face of that view.
Arrows show the direction of the
projection
ISO Symbol

17. Orthographic View Selection
Steps in selecting the front view.
Most natural position or use.
Shows best shape and characteristic contours.
Longest dimensions.
Fewest hidden lines.
Most stable and natural position.
Relationship of other views.
Most contours
Longest side
Least hidden lines
Best natural position

18. Orthographic View Selection
Most natural position.
Longest Dimension
Best shape description.
No hidden lines.

19. Orthographic View Selection Numbers
A decision must be made in accordance to how many views are needed on a drawing. Generally, three views are needed and, in some cases, only one or two.

20. Orthographic Example
2 Orthographic views
are used instead of
three.

21. Orthographic Example 3 View Orthographic Drawing Dimensions to show
size and shape.
Title Block gives
general information
about the part.

22. Placing and Locating Orthographic Views
Which orthographic views you need are based on the same rules we had in the sketching unit.
Steps in selecting the front.
Most natural position or use.
Shows best shape and characteristic contours.
Longest dimensions.
Fewest hidden lines.
Most stable and natural position.
Relationship of other views
Most contours.
Longest side.
Least hidden lines.
Best natural position.

23. Placing and Locating Orthographic Views
Parts are evenly spaced.
Enough white space is left
for dimensioning.
Third angle projection is
used.

24. Isometric Views
An isometric view is a pictorial view inserted in an orthographic drawing.
An Isometric, meaning equal measure, is created by rotating the object at equal angles to the projection plane in order to appear inclined and to show three faces.

25. Isometric Note one pictorial view shows Width and depth lines
height width and depth.
Width and depth lines
are drawn at 30 degrees from
the horizon line.

26. Isometric Views
Isometric View

27. Section Views
When a part has a lot of interior details, hidden lines can make the part hard to understand and dimension. To see the interior of these parts, we cut some of the part away. This allows for details to be seen clearly, as well as, giving us alternative locations to properly dimension the part.

28. Sectional Views Types of Sectional Views Half Full Offset Removed
Revolved
Broken-out
Aligned

29. Half Section Notice how the cutting plane line runs
through the center of the part and
there is no arrow head.
In a half section, one quarter of the part is cut away. This is done with symmetrical parts where you would like to show the outside, as well as, the inside details.

30. Full Section A full section is a view that shows what
the object looks like if it were cut in
half.
A cutting plane line is used to indicate how the front
view was cut. It is also labeled in case another section
is necessary. The arrows should point in the line of sight
as you are looking straight on at the section.
Section lines called Hatch lines are used to show where the
part is solid. This helps to see the detail that would be
normally blocked and only shown as hidden lines.

31. Offset Section
Interior features not in line with each other can be shown in an offset section view.
Note how the cutting plane line changes and follows the center of each feature.

32. Revolved Sections
Used when an object has a constant shape throughout the length that cannot be illustrated in an external view.
The section is revolved 90 degrees. It may be represented one of two ways, either broken away or not.

33. Not Broken Away Revolved Section
Section is revolved
90 degrees

34. Broken Away Revolved Section
Section is revolved
90 degrees and broken
away from part

35. Broken-out Section Views
A small portion of an object may be broken away to clarify an interior surface or feature. No cutting plane line is used.

36. Broken-out Section View
Section exposes
the interior surfaces

37. Auxiliary View
To accurately view the true dimensions of an inclined surface, one must create a view at 90 degrees from that inclined face. This is referred to as an Auxiliary View. This allows us to view the surface in its true size and shape.

38. Primary Auxiliary View
In order to see a feature in it’s true size and shape,
we must look at it straight on or perpendicular
to the plane in which the feature exists. Note
that in this view (the auxiliary view) the slotted
hole is true size and shape.
To obtain this view the auxiliary must be drawn
from the view that allows the line of sight to be
perpendicular to the desired feature.
Line of sight.
Many times a feature on a part cannot
be seen in true size and shape. When this
is the case we use an auxiliary view.

39. Detail Views
A drawing of an individual part that contains all the information needed to manufacture the object is referred to as a Detail Drawing. These drawings contain all the specifications, dimensions and views needed for production.
A Detail View may be necessary to illustrate small features on a part. This is achieved via breaking out and enlarging the feature.

40. Detail View
The feature is broken
out and enlarged for
clarity.

41. Assembly Drawings
Many products are composed of several different parts assembled into one. A drawing showing the working relationship of those parts is called an Assembly Drawing. This is achieved using views in the usual positions showing the layout out of the parts. A parts list is included on the drawing to identify the name, material and number of each piece.

42. Assembly Drawings
General
Exploded
Explosion factor
Trails
Tweaks

43. General Assembly Drawings
General Assembly Drawings are a set of drawings that include the detail drawings, assembly drawings and parts list needed in the production of an assembled object.

44. General Assembly Drawing
Parts List
Includes all detail
drawings of each
part
Includes the
Assembly
Drawing

45. Exploded Assemblies
Identification numbers are generally placed inside balloons and point to the part with a leader line
An Exploded Assembly
shows all the parts removed
from each other and aligned
along axis lines
Trials show the initial path the components moved along when the view was exploded
The explosion factor is the distance
the parts have been separated from
each other.
A parts list is included on the drawing to identify the name, material and number of each piece.

46. Parts List Specific part number. All parts will have specific numbers
assigned to them. This makes
computer data processing easier.
Description of part or the name.
Item number on the drawing.
How many parts are included
in the assembly.

47. Explosion Factor
The explosion factor is the distance the parts have been separated from each other.

48. Trails
Trails show the initial path the components moved along when the view was exploded

49. Tweaks
Is adjusting the distance or location of a part in an exploded assembly.
After
Before

50. Dimensioning
Views and dimensions provide a clear description of the shape and size of parts and their features.
Parts are fun to design, but dimensioning the part to be manufactured can be difficult.
Dimensioning takes time and patience to get it right. Errors in a drawing will most likely be found in the dimensioning.

51. Decimal
The most common form of dimensioning uses the decimal system. Precision is set by the number of decimal places.

52. Architectural
The Architectural Style of dimensioning is quite different from the decimal. Dimensions are shown in feet and inches.
Arrow heads can be the same as decimal dimensioning or can be displayed as architectural ticks.

53. Engineering
The engineering style of dimensions is shown here. The inch units are in decimal and feet and inches are displayed similar to the Architectural style of dimensioning.

54. Surveyor B
Surveying dimensions are given in north and south directions. The example here is said to be North 46 degrees, 48 minutes, 39 seconds West. This indicates the line points in the northwest. Normally a distance is given. A

55. Dual Dual dimensioning is a type that shows both metric and inch units
on the same drawing. There are two methods position and
bracket.
Dual
Position method: Places the metric dimension over the inch
dimension. Another acceptable practice is to place the metric
dimension before the inch dimension with a slash after the
metric dimension.
Bracket method: The bracket method places the metric
dimension in brackets. The metric dimension can be placed
above or to the right. Exactly what the units represent,
needs to be noted on the drawing.

56. Dimensioning Standards Types of Dimensions Linear
Dimensioning Arcs and Circles
Reference Dimensions
Dimensioning Special Features
Methods
Rules and Practices
Dimensioning Angles
Dimensioning Curved Features
Coordinate Dimensioning
Tolerance

57. Standards
In order for the drawings to be dimensioned so that all people can understand them, we need to follow standards that every company in the world must follow. Standards are created by these organizations:
ANSI -MIL
ISO -DOD
DIN -CEN
JIS

58. Standards Institutions
ANSI - American National Standards Institute - This institute creates the engineering standards for North America.
ISO - International Organization for Standardization - This is a world wide organization that creates engineering standards with approximately 100 countries participating.

59. Standards Institutions
DIN - Deutsches Institut für Normung - The German Standards Institute created many standards used world wide such as the standards for camera film.
JIS - Japanese Industrial Standard - Created after WWII for Japanese standards.
CEN - European Standards Organization

60. Standards Institutions
The United States military has two organizations that develop standards.
DOD - Department Of Defense
MIL - Military Standard

61. Dimensioning Methods
Dimensions are represented on a drawing using one of two systems, unidirectional or aligned.
The unidirectional method means all dimensions are read in the same direction.
The aligned method means the dimensions are read in alignment with the dimension lines or side of the part, some read horizontally and others read vertically.

62. Dimensions are aligned
Aligned Dimensions
Dimensions are aligned
with the dimension
lines

63. Unidirectional Dimensions
All dimensions and
notes are horizontal and read
from the bottom
of the sheet

64. Types of Dimensions
Their are two classifications of dimensions: size and location.
Size dimensions are placed in direct relationship to a feature to identify to specific size.
Location dimensions are used to identify the relationship of a feature to another feature within an object.

65. Size and Location Dimensions
Size dimensions
Location dimensions

66. Rules and Practices
Accurate dimensioning is one of the most demanding undertakings when designing parts.
Use the checklist to insure you have followed the basic dimensioning rules.

67. Dimensioning Checklist
Each dimension should be written clearly with only one way to be interpreted.
A feature should be dimensioned only once.
Dimension and extension lines should not cross.
Dimension each feature.
Dimension features or surfaces to a logical reference point.

68. Dimension Checklist
Dimension circles with diameters and arcs with a radius.
A center line should be extended and used as an extension line.
Dimension features on a view that clearly shows it’s true shape.
Dimension with enough space to avoid crowding and misinterpretation.

69. Dimension Checklist
Extension lines and object lines should not overlap.
Dimensions should be placed outside the part.
Center lines or marks should be used on all circles and holes.

70. Linear Dimensioning
The accuracy of the final product is determined by the dimensions on the drawing. If all the dimensions originate from a common corner of the part, the object will be more accurate. This is referred to as Datum Dimensioning. Datum's insure the tolerance or errors in manufacturing do not accumulate.

71. Linear Dimensioning
Dimensioning from feature to feature is known as Chain Dimensioning. It is commonly used and easy to layout. It does have possible consequences in the manufacturing of a part. Tolerances can accumulate making the end product larger or smaller than expected.

72. The chain dimensioning layout can have an effect on the final length of the part ranging from 1.47
This step can be .490
To .510 wide
This step can be .490
To .510 wide
This step can be .490
To .510 wide
The chain dimensioning layout can have an effect on the final height of the part ranging from .72
to .78
This step can be .240
To .260 tall
This step can be .240
To .260 tall
This step can be .240
To .260 tall

73. Chain Dimensioning
Placing an overall dimension will limit the chain effect of the
Tolerance build up
Placing an overall dimension will limit the chain effect of the
Tolerance build up

74. Datum Dimensioning This distance can be 1.49 to 1.510 wide
The dimensions originate from a common edge (DATUM) of the part
The dimensions originate from a common edge (DATUM) of the part
This distance can be .990 to wide
This step can be .490
To .510 wide

75. Dimensioning Angles
Angled surface may be dimensioned using coordinate method to specify the two location distances of the angle.
Angled surfaces may also be dimensioned using the angular method by specifying one location distance and the angle.

76. Dimensioning Angles
Coordinate Method
Angular Method

77. Dimensioning Arcs and Circles
Arcs and circles are dimensioned in views that show the arc or circle.
Arcs are dimensioned with a leader to identify the radius in some cases a center mark is included.
Circles should have a center mark and are dimensioned with a leader to identify the diameter.

78. Dimensioning Curved Features and Arcs
Small arcs do not need
center marks. Arrow can
be outside.
Large Arcs use center
marks.
Use a capital “R” for
dimensioning arcs.
Or the arrow can be inside
for small arcs.

79. Diameters A full circular object should be dimensioned
using it’s diameter. Holes should use hole
notes.
Cylindrical parts may show their diameters in this
manner. Dimensioning on the right side view
would be too crowded.
This specification
calls for a hole with
a .5 diameter
and 1.00 deep

80. Dimensioning Curved Features
Points are placed along the contour
and are dimensioned from the datum
Datum

81. Reference Dimensions Designates more than one of the same feature.
In this case it is identifying there are
two identical holes

82. Chamfers External chamfer for 45 degree chamfers
only. There are two options.
External chamfer for angles other than
45 degrees.
Internal chamfers.

83. Fillets and Rounds Use a capital “R” for dimensioning the arc. Fillets
Small arcs do not need
center marks. Arrow can
be outside the arc.
Rounds
Large arcs use center
marks.

84. Conical Tapers

85. Slot Dimensioning The two methods shown on the left are the acceptable
methods for
dimensioning slotted
holes.

86. Hole Location: Polar Coordinates
Polar dimensioning locates
features by the use of angles

87. Rectangular Coordinates
Rectangular coordinates use linear dimensions
to dimension the hole locations
multiple holes are dimensioned from another

88. Rectangular Coordinates
Linear Coordinates
are used to
locate hole dimensions

89. Keyways
Keyway
Keyways
Shaft
Hole

90. Tolerance Dimensioning
Perfection is difficult to obtain. A tolerance is associated with dimensions on a drawing to illustrate the permissible variation in size or location. A tolerance specifies how much the dimension may vary from the designated size on the drawing.

91. Tolerance Limits
The largest size an object can be made to is the upper limit. The smallest size an object can be made to is the lower limit.
Upper limit
.126
Lower limit
.125
Upper limit
Is .380
Lower limit
Is .373

92. Dimensioning Tolerances
If your limits deviate above and
below your basic size you have bilateral
dimensioning.
This dimension is
unilateral because
the size may only
deviate in one direction.
Limit Dimensioning
shows the size of the
upper limit and the lower
limit.

93. Allowances Some parts fit together requiring an
allowance to be specified.
It is the tightest possible fit
between two parts
If this part is made
larger than .380 it
will not fit together
properly

94. Alphabet of Lines Short Break Line: A freehand
drawn line that shows where a part is
broken to reveal detail behind the part or
to shorten a long continuous part. (See
example of Long Break Line
on the next slide.)
Hidden Line: Lines used to
show interior detail that is not visible
from the outside of the part.
Object Line: Thick lines
about .6mm(.032in) that show
the visible edges of an object.
Center Line: Lines that define
the center of arcs, circles or symmetrical parts.
They are half as thick as an object line.
Section Lines: Lines are used to
define where there is material
after a part of the object is cut away.
Construction Line: Very lightly
drawn lines used as guides to help draw
all other lines and shapes properly.
Usually erased after being used.

95. Alphabet of Lines Long Break Lines: Break lines are used
To indicate we have shortened
the drawing to use
our space more efficiently.
Dimension lines are used to
show distance. Arrows are drawn on the
ends to indicate where the dimension line starts and ends.
The actual distance is placed in the middle of this
line. Dimension lines are used in conjunction
with extension lines to properly
dimension objects.
Extension lines are used to show where
a dimension starts and stops on an object.
The line should begin about 1/16” away from the
part to prevent confusion with the object lines
Cutting Plane Line: A line used to
designate where the part has been cut
away to see detail. The arrows
point in the direction that you are
looking.
Leader lines are used to show dimensions
of arcs or circles. They are also used to
connect notes with features. The line with
the arrowhead should be diagonal while the
Line connecting to the note is horizontal
How many lines from the
previous slide can you identify
here?

96. Line Types and Specifications
Arrow heads point directly to the object that is being dimensioned
or the extension lines at the end of the dimension. Arrow heads
are made 3 times as long as they are wide.
Each succeeding dimension line
should be 6mm from the previous one.
Extension lines are used to establish the extent of the dimension.
Arrows from the dimension line should touch the extension
line. Extension lines should have a small space between the end
and the object that is being dimensioned. The extension line
should also extend 3mm beyond the last dimension line noted.
The dimensioning system used here is unidirectional. This is the
most common. Another system you may see is aligned. If this
drawing were using the aligned system the dimension, we are
pointing to would be read horizontally from the right of the
drawing or turned counter clockwise 90 degrees.
Dimension lines are used to identify distances of features.
It has arrow heads at the end to identify the extents. There
is a break in the middle to place the dimension. Dimension
lines should be 10mm away from the object that is
being dimensioned.

97. Annotation
Local notes identify specific features that need a special operation.
Hole notes are one such example. This note is placed with leaders
at the location of the feature it pertains to.
General notes are information that pertains to the entire drawing,
unless specified in a local note. General notes are usually
placed in the title block.

98. with numbers and symbols.
Hole Dimensioning
Holes are specified
with numbers and symbols.
Diameter
Through
Depth
Counterbore or
Spotface

99. Hole Dimensioning
Finish Mark
Countersink

100. Hole Dimensioning A countersunk hole has an angular cut on the top
edge to allow flathead screws
to sit below the surface
A spotface is a shallow cut used on
castings to create a flat surface for
bolts.
Boss is a raised surface used in castings
for reinforcement. Finished on top to
create a flat surface for the bolt to seat.
A blind hole is drilled
to a specific depth.
A counter bored hole has a step so
the head of a bolt can sit
below the surface.
Through hole is drilled completely
through the material.

101. Thread Notes This number can be 3,4,5,6,7,8,9. It is the
grade of tolerance in the threads from
fine to course. The H is for allowance
G would be a tight allowance and
H is no allowance.
Prior to THRU you may have an LH
for left hand thread.
Finally THRU or a depth may
be specified.
M for Metric
Nominal Diameter
Pitch of the threads.
Notes the threads are cut all
the way through the hole. Depth
can be specified here as well as LH for
left hand thread.
Identifies course or fine
thread. In this case course.
F for fine.
Major Diameter
Threads per Inch
Threads are dimensioned with
the use of local notes. We will
discuss two methods: the ISO
and the Unified National Thread
method.