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Dimension lines:

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Title: Dimension lines:


1
Extension Line
Dimension lines Shows the beginning and the end
of the measurement. Terminated by
arrowheads. Thin line (dark) weight. Should be
broken to allow for the numbers to be
inserted. Must be a minimum of .375" or 10mm away
from the object. Must be a minimum of .250" or
6mm away from parallel dimension lines.
Dimension Line
2
Extension Line
Extension lines Extend the edge of the
object. Thin line (dark) weight. There should be
a visible gap (.0625" or 1mm) between the object
and the start of the extension line. Extension
lines should extend about .125" or 2.5mm beyond
the last dimension line.
Dimension Line
3
Leader lines Are drawn from a note or dimension
to place where the note applies. Are drawn at an
angle (usually 30, 45, or 60). Should have a
short (.125" or 3mm) shoulder that if extended,
would intersect the note at mid-height. May end
with an arrowhead or dot. Leaders should not
cross over or through other leaders or dimension
lines. Avoid making leaders parallel or
perpendicular to visible edges. .
4
Arrowheads Can be solid filled or open. Should
be approximately .125" or 3mm long. Should be
approximately 2.5 to 3 times as long as wide.
5
DIMENSIONING INCLUDES MEASUREMENTS, NOTES AND
SYMBOLS
6
6
1. Phantom 2. Section 3. Hidden 4.
Cutting/viewing 5. Leader 6. Hidden 7. Center 8.
Visible/object 9. Extension 10. Break 11.
Visible/object 12. Section 13. Extension 14.
Break 15. Dimension
7
Procedures for using decimal and metric
measurement. Decimal inches Decimals are the
ANSI standard. Decimals are easier to add,
subtract, multiply and divide than
fractions. Preferably, decimals should be rounded
to two decimal places. Omit zero before the
decimal point for values of less than
one. Fractional inches Used where close
tolerances are not important. The horizontal
fraction bar is preferred. Metric Where linear
measurement are less than 10,000 millimeters, the
millimeter is the standard unit of measure. The
abbreviation for millimeters (mm) is usually
omitted when all dimensions are in
millimeters. The period is used as a decimal
point only in English speaking countries, others
use a comma.
8
The number one rule of dimensioning is that of
clarity. Place dimensions where the shape is best
shown. Shortest dimensions placed closest to the
object. Group and align dimensions when
possible. Avoid duplicate and/or unnecessary
dimensions. Try to avoid placing dimensions
inside a view. Avoid crowding dimensions. Avoid
dimensioning to hidden features. Place dimensions
between the views to which they relate. Lines
should be thin and contrast noticeably with
visible lines. Dimensions should be included that
describe both size and location of features. The
diameter of cylinders is dimensioned in the
rectangular view. The diameter of machined holes
is dimensioned in the circular view.
9
Cartesian Coordinate System
10
Polar CoordinatesPolar coordinates used when you
need to draw the next points at specify angle.
Polar coordinates system in AutoCAD specifies
distance length at which angle. Using polar
coordinate, points entered by typing
_at_distanceltangle Enter
Polar Coordinate System
11
Absolute Coordinate System
Relative CoordinatesAfter first points entered,
your next points can be entered by specifying the
next coordinate compare/relative from the first
points. The relative coordinate started with
symbol _at_ tell AutoCAD it was a relative
coordinates. Using relative coordinate, points
entered by typing _at_x,y Enter
12
Boolean Commands. Union ( or ?) adds parts
together Subtract or Difference ( ? ) removes
parts or features Intersection ( or ? )
Intersects overlapping volumes into a single
feature
13
Purpose of a Sketch
  • Quickly easily get an idea on paper
  • Design sketches
  • Freehand technical sketches
  • Technical illustrations

14
Freehand Technical Sketch
15
Design Sketch
16
Technical Illustration
17
Sketching Lines
  • Vertical lines
  • Top to bottom
  • Long straight lines
  • Series of short straight lines

18
Sketching Circles Arcs
  • Begin by lightly constructing a square

19
Sketching Angles
  • Begin with 90 angle

60
45
30
Subdivide once
Subdivide twice
20
Sketching
  • Types of Sketches
  • Single-view
  • Multi-view
  • Pictorials

21
Single-view Sketching
  • Technical purposes
  • Front view
  • Most descriptive features

22
Multi-view Sketching
  • Technical sketch
  • Front view
  • Top view
  • Side view

23
Pictorial Sketches
  • Quickly communicate an idea
  • Three dimensions in one view
  • Width
  • Height
  • Depth

24
Pictorial Sketches
  • Three (3) types
  • Isometric
  • Oblique
  • Perspective

25
Isometric Sketch
HEIGHT
WIDTH
DEPTH
26
Isometric Sketching
  • Three equally spaced axes of 120

27
Isometric Sketching
  • Receding lines
  • Typically 30 off horizontal

28
Isometric Sketching
  • Circular shapes appear as ellipses

29
Isometric Ellipses
  • Correct ellipse orientation

30
Isometric Sketching
  • Non-Isometric lines
  • Locate endpoints and connect

31
Oblique Sketch
HEIGHT
DEPTH
WIDTH
32
Oblique Sketching
  • Front view is drawn true shape and size

33
Oblique Sketching
  • Receding edges are usually drawn at an angle of
    30, 45, or 60

34
Oblique Sketching
  • Circles and curves drawn on frontal plane will
    appear true shape and size

35
Perspective Sketches
2-Point Perspective
1-Point Perspective
36
Perspective Sketches
  • Objects appear as the eye would see them
  • Most realistic type of pictorial sketch
  • Most difficult pictorial sketch to draw

37
Drafting Equipment
  • Drawing board/table

38
Drafting Equipment
  • Drawing Horizontal lines
  • T-square
  • Parallel edge
  • Drafting Machine
  • Arm/elbow type
  • Track type

39
Drafting Equipment - Triangles
  • 45 Triangle
  • Draw vertical lines and lines _at_ 45
  • 30 x 60 Triangle
  • Draw vertical lines and lines _at_ 30 and 60
  • Adjustable Triangle
  • Draw lines _at_ 0 to 90

40
Drafting Equipment - Leads
SOFT Very soft leads, smudge easily. Used for art
work of various kinds and full-size details in
architectural drawing.
MEDIUM General purpose work. Softer grades
(right) used for technical sketching, lettering,
freehand work. Harder grades (left) used for line
work on machine architectural drawings.
HARD Used where extreme accuracy is required.
Softer grades (right) used for line work on
engineering drawings. Draw very light lines.
41
Drafting Equipment - Scales
  • Engineer (Civil)
  • Mechanical drafter
  • Metric
  • Architecture

42
Drafting Media Types
  • Vellum
  • Tracing paper treated to make it more transparent
  • Most commonly used drafting media
  • Polyester drafting films (mylar)
  • Very transparent, strong, and lasting
  • Strongest drafting media
  • Bond
  • Standard printing and copy paper

43
Drafting Media Sizes
E 44 X 34 48 X 36
D 34 X 22 36 X 24
C 22 X 17 18 X 24
B 17 X 11 12 X 18
A 11 X 8.5 9 X 12
44
Lettering
  • Practice of adding clear, concise words on a
    drawing to help people understand the drawing
  • Notes lettered on rough sketches are functional
    and important to operation
  • Simple freehand lettering completes the idea
    captured in a sketch

45
Lettering Composition
  • Letter and word spacing should be about uniform
  • Space between words should equal the approximate
    width of the letter O
  • Background area between letters should appear
    equal

46
Lettering
  • Practice of adding clear, concise words on a
    drawing to help people understand the drawing
  • Notes lettered on rough sketches are functional
    and important to operation
  • Simple freehand lettering completes the idea
    captured in a sketch

47
Lettering Composition
  • Letter and word spacing should be about uniform
  • Space between words should equal the approximate
    width of the letter O
  • Background area between letters should appear
    equal

48
Guidelines
  • Horizontal guidelines keep letters the same
    height
  • Vertical guidelines aid the eye in keeping
    letters from slanting
  • Guidelines are drawn very light and very thin
  • Do not need to be erased
  • Uniform vertical space should be left between
    lines of letters

49
Types of Lettering
  • ANSI (American National Standards Institute)
  • Recognizes the use of single-stroke Gothic
    letters
  • Letters are formed using a series of strokes
  • Typically all capital letters are used
  • Most common lettering on Engineering Drawings
  • Vertical, Uppercase, Gothic

50
Lettering Standards
  • Typically, most letters are .125 (3mm) tall
  • Fractions are typically twice as tall as numbers
  • Fraction bar is horizontal and does not touch the
    numbers

51
Drawing Lines
  • Use parallel edge (or T-square) to draw
    horizontal lines
  • Lean pencil at about 60
  • Use triangles to draw vertical and inclined lines

52
Drawing Lines at Standard Angles
53
Scale Drawings
  • Measurements can be full size or in some exact
    proportion to full size
  • Triangular scales are typically used to allow for
    more scales per stick
  • Scales are noted on drawings as
  • Drawn units actual units
  • Drawn units actual units

54
Reading a Mechanical Scale
  • FRACTIONAL INCH SCALE (FULL SIZE)

55
Reading a Mechanical Scale
  • FRACTIONAL INCH SCALE (HALF SIZE)

56
Reading a Decimal Scale
  • DECIMAL INCH SCALE (FULL SIZE)

57
Reading a Decimal Scale
  • DECIMAL INCH SCALE (HALF SIZE)

58
Reading a Metric Scale
  • 11 SCALE (1mm DIVISIONS)

59
Reading a Metric Scale
  • HALF SCALE (2mm DIVISIONS)

60
Alphabet of Lines
  • Construction lines
  • Thin and light
  • .020 (0.5mm)
  • Hard lead (4H)
  • Visible lines
  • Thick and dark
  • .028 (0.7mm)
  • Softer lead (F or HB)

61
Alphabet of Lines
  • Hidden lines
  • Thin and dark
  • .020 (0.5mm)
  • Softer lead (F or HB)
  • .125 (3mm) long dashes w/ .030 (1mm) spaces in
    between

62
Alphabet of Lines
  • Center Lines
  • Thin and dark
  • .020 (3mm)
  • Softer lead (F or HB)
  • .125 (0.5mm) dash in center w/ .030 (0.1mm)
    spaces between longer lines

63
Alphabet of Lines
  • Dimension, Extension, Leader Lines
  • Thin and dark
  • .020 (0.5mm)
  • Softer lead (F or HB)

6.125
64
Multiview Drawing
  • Another name for orthographic projection is
    multiview drawing
  • Involves visualization and implementation
  • Ability to see clearly in the minds eye an
    object
  • Process of drawing the object

65
Multiview Drawing
  • A system that allows you to make a
    two-dimensional drawing of a three-dimensional
    object

66
Viewing Objects
  • A box is formed by six mutually perpendicular
    planes of projection that are located around the
    object

67
Viewing Objects
  • Lines are formed on the planes by projecting the
    edges of the object onto the planes
  • These images are called views
  • There are six views formed by the planes of a box

68
Viewing Objects
  • Unfolding the box produces an arrangement of the
    six views

69
Choosing Views
  • Most commonly used views
  • Front View
  • Top View
  • Right Side View
  • Most descriptive view is typically designated as
    the Front View

70
Choosing Views
  • Complex objects require three views to describe
    its shape
  • Simple objects can be described with two views
  • Ex Soda Can
  • Thin objects can be described with only one view
  • Depth is given in a note
  • Ex Erasing Shield

71
Object Dimensions
  • All objects have 3 dimensions
  • Height
  • Distance from top to bottom
  • Width
  • Distance from side to side
  • Depth
  • Distance from the front to back

72
Object Dimensions
  • Front View
  • Shows width height
  • Top View
  • Shows width depth
  • Side View
  • Shows height depth

73
Drawing Views of Objects
  • Depth can be projected between views by using a
    45 miter line

74
Line Types - Visible
  • Edges that can be seen in a given view areVisible
    or Object lines
  • Visible lines are thick and dark
  • .028 or .7mm
  • F or HB lead

75
Line Types - Hidden
  • Edges that cannot be seen from a given view are
    indicated by Hidden lines

76
Line Types - Hidden
  • Drawing hidden lines
  • .125 (3mm) dashes
  • .0625 (1mm) spaces between dashes
  • Thin .020 (.5mm)
  • Dark F or HB lead

77
Line Types Center
  • Center lines indicate axes of symmetry

78
Placement of Views
  • Views should be visually balanced within the
    working space

79
Steps for Centering a Drawing
  • Draw in views using light construction lines

80
Straight Edges
  • Edges that are perpendicular to a plane of
    projection appear as a point

2
3
1
81
Straight Edges
  • Edges that are parallel to a plane of projection
    appear as lines
  • Edges that are inclined to a plane of projection
    appear as foreshortened lines

82
Curved Edges
  • Curved edges project as straight lines on the
    plane to which they are perpendicular
  • Curved edges project as curved lines on the
    planes to which they are parallel or inclined

83
Inclined Surfaces
  • Inclined surfaces appear as an edge in two
    opposite principal views, and appear
    foreshortened (not true size) in all other
    principal views.

84
Oblique Surfaces
  • Oblique surfaces do not appear either as an edge
    or true size in any principal view.

85
Angles
  • Acute Angle
  • Measures less than 90
  • Obtuse Angle
  • Measures more than 90
  • Right Angle
  • Measures exactly 90
  • Vertex
  • Point at which two lines of an angle intersect

86
Circle
  • Radius
  • Distance from the center of a circle to its edge
  • Diameter
  • Distance across a circle through its center
  • Circumference
  • Distance around the edge of a circle
  • Chord
  • Line across a circle that does not pass at the
    circles center

87
Circle
  • Has 360
  • Quadrant
  • One fourth (quarter) of a circle
  • Measures 90
  • Concentric
  • Two or more circles of different sizes that share
    the same center point

88
Triangles
  • Equilateral
  • All three sides are of equal length and all three
    angles are equal
  • Isosceles
  • Two sides are of equal length
  • Scalene
  • Sides of three different lengths and angles with
    three different values

89
Triangles
  • Right Triangle
  • One of the angles equals 90
  • Hypotenuse
  • The side of a right triangle that is opposite the
    90 angle

90
Quadrilaterals
  • Square
  • Four equal sides and all angles equal 90
  • Rectangle
  • Two sides equal lengths and all angles equal 90
  • Trapezoid
  • Only two sides are equal length

91
Quadrilaterals
  • Rhombus
  • All sides are equal length and opposite angles
    are equal
  • Rhomboid
  • Opposite sides are equal length and opposite
    angles are equal

92
Regular Polygons
  • Pentagon
  • Five sided polygon
  • Hexagon
  • Six sided polygon
  • Octagon
  • Eight sided polygon

93
Regular Polygons
  • Distance across flats
  • Measurement across the parallel sides of a
    polygon
  • Distance across corners
  • Measurement across adjacent corners of a polygon

94
Solids
  • Prism
  • Right Rectangular
  • Right Triangular

95
Solids
  • Pyramid
  • Torus

96
Geometric Terms
  • Circumscribe
  • Process of creating a polygon that fully encloses
    a circle and is tangent to all of the polygons
    sides
  • Inscribe
  • Process of creating a polygon that is fully
    enclosed by a circle at its corners

97
Geometric Terms
  • Bisect
  • Divide into two equal parts
  • Tangent
  • A line and arc, or two arcs that touch each other
    at one point only

98
Geometric Symbols
  • Angle
  • Triangle
  • Radius
  • Diameter
  • Parallel
  • Perpendicular
  • Square
  • Centerline

R
99
Terms Definitions
  • Parliamentary Procedure
  • A set of rules for conduct at meetings which
    keeps assemblies orderly and guarantees that all
    people have equal opportunity to express
    themselves
  • Item of Business
  • A single matter to be discussed or acted on by an
    organization

100
Terms Definitions
  • Minutes
  • The official written record of what was said and
    done in a meeting

101
Terms Definitions
  • Standing
  • A regular committee which usually serves for a
    one year period to plan/carry out activities that
    fall w/in a certain subject matter
  • Majority vote
  • More than half the votes cast
  • Two-thirds vote
  • Two-thirds or more of the legal votes cast

102
Terms Definitions
  • Second
  • An indication by a member that he or she wants to
    consider the motion just proposed by another
    member

103
Terms Definitions
  • Minority
  • Less than half
  • Majority
  • More than half
  • Quorum
  • The number of members needed to be present to
    legally transact business

104
Motions their Purposes
  • Main motion
  • To present an item of business for consideration
    and action by the assembly
  • Amend
  • To change a main motion in some way add to, take
    away from, or substitute words for
  • Postpone
  • To defer action of a motion until a later time

105
Steps for Processing aMain Motion
  • Obtain the floor
  • Be recognized by the Chair by standing and saying
    Mr. Chairman
  • Chair assigns the floor
  • The Chair recognizes one of the members by
    pointing or nodding
  • Member makes the motion
  • States I move that
  • Another member seconds the motion

106
Steps for Processing aMain Motion
  • Chair restates the motion to the assembly
  • Motions is discussed/debated by the assembly
  • Vote is taken on the motion
  • Vote is announced and appropriate action is taken

107
Order of Business
  • Opening
  • Call to order, emblem ceremony, pledge to flag)
  • Roll Call
  • Reading of Secretarys minutes
  • Treasurers report
  • Committee reports
  • Standing
  • Ad Hoc

108
Order of Business
  • Unfinished business
  • New business
  • Program
  • Speaker, film, etc
  • Adjournment
  • Refreshments

109
Raps of the Gavel their Purposes
  • One rap
  • Everyone should be seated
  • Two raps
  • The meeting is called to order
  • Three raps
  • Everyone should stand up
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