Basic Dimensioning Practices
Sacramento City College
EDT 310
EDT 310 - Chapter 18 - Basic Dimensioning Practices
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Dimensioning Practices
 Dimensional
information includes
 Size
dimensions.
 Location dimensions.
 Notes.
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Dimensioning Practices
 Size
Dimensions
 Size
dimensions provide the size of physical
features.
 Diameter
of holes
 Width
 Length
 Depth
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Dimensioning Practices
 Location
Dimensions
 Location
dimensions provide the location of
physical features.
 Location
of holes from end
Datum Dimensioning
 Chain Dimensioning

 Location
of windows/doors in buildings
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Dimensioning Practices
 Notes
 Notes
give information about individual or
specific features on the drawing.
 They are attached to the feature with a leader
line.
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Dimensions
 Each
drafting field uses a different type of
dimensioning technique
 Architectural.
 Mechanical.
 Civil.
 Electronics.
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Dimensions
 Drafters
should place dimensions in
accordance with company and industry
standards.
 Use
the company standard FIRST.
 When
no company standard exists, use
industry standards.
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Dimensioning Standards
 ASME
Y-14.5M-1994 Dimensioning and
Tolerancing
 Standard
emphasized in the textbook.
 M - means metric.
 1994 is the year it was published.
 ASME is the American Society of Mechanical
Engineers.
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Dimensioning Formats
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Dimensioning Formats
 Unidirectional
Dimensioning is
 “Unidirectional”
means one direction.
 All dimension numbers and notes are placed
horizontally on the drawing sheet.
 Numbers are read from left to right when
viewed from the bottom of the drawing sheet.
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Aligned Dimensioning
 Aligned
Dimensioning is
 Used
on architectural drawings.
 Horizontal dimensions are read horizontally.
 Vertical dimensions are read vertically from
the right edge of the sheet.
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Dimension Styles used by Particular
Field of Work
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Dimensions
 Mechanical
Field.
 Uses
Unidirectional dimensioning
 Dimensioning parts.
 Dimension Characteristics
 Uses
arrowheads for terminators.
 Dimension line is broken
 Dimension number is centered inside dimension
line.
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Dimensions
 Architectural
Field.
 Uses
Aligned dimensioning
 Dimension Characteristics
 Uses
“tic” marks for terminators.
 Dimension line is unbroken.
 Dimension number is centered over dimension
line.
 Dimension is aligned with surface.
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Dimensioning Practices
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Dimensioning Practices
 Dimensioning
 Product
 What
practices depend on
requirements.
are you making?
 Manufacturing
 Extreme
accuracy.
precision vs approximate dimensions.
 Standards.
 What
dimension standards exist for your industry?
 Tradition.
 How
has your industry dimensioned in the past?
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Dimensioning Practices
 Compare
dimensioning practices for:
 Automobile.
(decimal inches)
 Architecture. (feet, inches, fractions of inch)
 Microprocessor chip. (1/10,000 to 1/100,000
of an inch
 Civil. (Miles or kilometers)
 Each
dimension type is appropriate for
that discipline.
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Dimensioning Practices
 Precision
is indicated by decimal places
 Automobile.
3
(decimal inches)
inches vs 3.0010 inches
 Architecture.
 40.343245
feet (???) !!
 Civil.
 40.365789
miles (???) !!
 Precision
must be appropriate for that
discipline.
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Dimensioning Practices
 The
number of decimal places shown on a
dimension increases manufacturing costs!
 Paper
weight measurements
 3.0000”

 3”
x 4.0000” x 2.0000”
Vs
x 4” x 2”
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AutoCAD Dimensioning Commands
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Dimensioning Commands






DLI
DAL
DAN
DBA
DCE
DCO
DIMLINEAR
DIMALIGNED
DIMANGULAR
DIMBASELINE
DIMCENTER
DIMCONTINUE







DED
DRA
DDI
DOR
DOV
DST
LE
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DIMEDIT
DIMRADIUS
DIMDIAMETER
DIMORDINATE
DIMOVERRIDE
DIMSTYLE
LEADER
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The DIMLINEAR Command
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DIMLINEAR Command
 Use
DIMLINEAR command for
 Length
 Width
 Depth
 Use
DIMLINEAR for
 Linear
dimensions – (X,Y, Z)
 Horizontal
 Vertical
 Slanted
surfaces
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DIMLINEAR Command
 All
dimension components are placed
automatically by AutoCAD.
 Extension
lines.
 Dimension lines.
 Dimension text and arrowheads.
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DIMLINEAR Command
 To
DIMLINEAR command:
 Pick
the Linear Dimension button on the
Dimension toolbar.
 OR
 Pick
Linear from the Dimension pull-down
menu.
 OR
 Type
DLI or DIMLINEAR at the Command:
prompt.
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DIMLINEAR Command
 Command
Sequence:
Command: DLI or DIMLINEAR
Pick First extension line origin.
Pick Second extension line origin.
Pick Location of dimension.
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First Extension Point
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Second Extension Point
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Dimension Location
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DIMLINEAR Command
 When
picking extension line origins:
 Use
one of the OSNAP modes for accuracy.
 ENDpoint is a good one to use.
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DIMLINEAR Command
 The
DIMLINEAR command allows you to
generate dimensions that are
 Horizontal.
 Vertical.
 Aligned
with a slanted surface.
 Rotated at a specified angle.
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DIMLINEAR Command
 Command:
 The
DIMLINEAR
following prompt appears:
Dimension line location (Mtext/Text/Angle/Horizontal
Vertical/Rotated)
 Notice
submenu choices
 Mtext
 Text
 Angle
 Horizontal
 Vertical
 Rotated
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DIMLINEAR Command
 Dimension
line location
 Is
the default option selection.
 Click the location where you want the dimension
line.
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DIMLINEAR Command
 Mtext
 Accesses
the Multiline Text Editor.
 The << >> (Chevrons) indicate the current
dimension value.
 The < > is an intelligent value.
 Normally, you should NOT delete the < >.
 If you want the dimension changed, delete < >.
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MTEXT Option
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DIMLINEAR Command
 Text
(Uses DTEXT)
 Uses
the Command Line to change the dimension
text.
 Angle
 Allows
you to change the dimension text angle.
 Horizontal
 Sets
dimensions to horizontal distances only.
 Vertical
 Sets
dimensions to vertical distances only.
 Rotated
 Allows
you to change the angle for dimension line.
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Text Option chosen
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Angle
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Vertical
Horizontal
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Rotated
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The DIMALIGNED Command
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Dimensioning Angled Surfaces
 DIMALIGNED
 Use
for dimensioning a surface drawn at an
angle.
 DIMALIGNED
 functions
similarly to the DIMLINEAR
command
 aligns dimension lines with the surface.
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The QDIM Command
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The QDIM Command
 For
DLI and DAL,
 You
must pick the extension line origins.
 QDIM
 Lets
you pick a geometry
 Circle,
Rectangle, etc.
 Extension
line origins are AUTOMATICALLY
selected.
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The DIMANGULAR Command
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DIMANGULAR Command
 Use
DIMANGULAR command to
 Dimension
the included angle of an arc.
 The
arc’s center point becomes the angle
vertex and
 the two arc endpoints are the origin.
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Endpoint
Origin
Endpoint
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DIMANGULAR Command
 Use
DIMANGULAR command to dimension
part of a circle.
 First
pick point on a circle becomes the
endpoint of the first extension line.
 Second pick point becomes the endpoint of
the second extension line.
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Endpoint
Origin
Endpoint
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DIMANGULAR Command
 Access
the DIMANGULAR command by:
 Pick
the Angular Dimension button on the
Dimension toolbar
 Pick Angular in the Dimension pull-down
menu
 Type DAN or DIMANGULAR at the
Command: prompt.
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DIMANGULAR Command
 If
there is enough room, AutoCAD will
 Place
the
 Dimension
text
 Dimension line arc, and
 Arrowheads inside the the extension lines.
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DIMANGULAR Command
 If
there is not enough room AutoCAD will
 Place
the arrowheads outside and
 Place the number outside the dimension lines.
 If
space is very small, ALL will be placed
outside.
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Dimensioning Shapes
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Dimensioning Flat Surfaces
 Dimension
flat surfaces by giving
measurements for each feature.
 Architectural
drafting - show all dimensions.
 Refer to Figures 18-17, 18-18
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Architectural
Style
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Mechanical Style
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Dimensioning Cylindrical Shapes
 Cylinders
– Dimension
 The
diameter and the length in one view.
 Use the view where the cylinder appears
rectangular.
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Dimensioning Square Features
 Square/Rectangular
shapes
 Dimension
in views where the length and
height are shown.
 Refer to Figure 18-20
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Dimensioning Conical Shapes
 Conical
shapes - dimension two ways:
 1.
Give the diameters at both ends and the
length.
 2.
Give the taper angle and length.
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Conical Shapes #1
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Conical Shapes #2
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Dimensioning Hexagonal Shapes
 Hexagonal
shapes - Dimension by giving
 the
distance across the flats and
 the length.
 Refer to Figure 18-22
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Location Dimensions
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Location Dimensions
 Location
dimensions are used to locate
features on an object.
 Holes
 Offsets
 Location
dimensions do not provide size.
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Location Dimensions
 Holes
and arcs are dimensioned in the
view where they appear circular.
 Rectangular
their edges.
features are dimensioned to
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Location Dimensions
 Rectangular
coordinates and polar
coordinates are the two location
dimensioning systems.
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Location Dimensions
 Rectangular
coordinates are linear
dimensions used to locate features from
surfaces, centerlines or center planes
 Use
DIMLINEAR command.
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Location Dimensions
 Polar
coordinates uses angular dimensions
to locate features from surfaces,
centerlines or center planes.
 Use
DIMANGULAR command.
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Datum Dimensioning
DIMBASELINE
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Datum Dimensioning
 In
Datum or Baseline dimensioning,
dimensions originate from common
surfaces, centerlines or center planes.
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Datum Dimensioning
 Datum
Dimensioning is commonly used in
mechanical drafting because each
dimension is independent of the others.
 AutoCAD
refers to Datum Dimensioning as
DIMBASELINE or DBA
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Chain Dimensioning
DIMCONTINUE
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Chain Dimensioning
 Chain
dimensioning
 Is
rarely used in mechanical drafting.
 has less accuracy, since each dimension is
dependent on the previous dimensions.
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Chain Dimensioning
 If
chain dimensioning is used, include an
overall dimension to help insure accuracy.
 AutoCAD
refers to chain dimensioning as
DIMCONTINUE.
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Chain Dimensioning
 Chain
Dimensioning is commonly used in
architectural drafting.
 Architectural
drafting commonly also
shows an overall dimension with the chain
dimensioning.
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Datum Dimensioning
 AutoCAD
refers to datum dimensioning as
Baseline dimensioning.
 Use the DIMBASELINE command.
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Datum Dimensioning
 Use
the DIMBASELINE command to
perform baseline dimensioning.
 Pick
the Baseline Dimension button in the
Dimension toolbar
 OR
 Pick
Baseline in the Dimension pull-down
menu
 OR
 Type
DBA or DIMBASELINE at the
Command: prompt
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Datum Dimensioning
A
dimension must exist first before the
DIMBASELINE command can be used.
 AutoCAD
will use the most recently drawn
dimension unless you specify another one.
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Datum Dimensioning
 In
datum dimensioning
 AutoCAD automatically spaces and places
 Extension
lines.
 Dimension lines.
 Arrowheads.
 Numbers.
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Chain Dimensions
 Create
chain dimensions by:
 Picking
the Continue Dimension button in the
Dimension toolbar
 OR
 Picking
Continue in the Dimension pull-down
menu
 OR
 Typing
DCO or DIMCONTINUE at the
Command: prompt
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The QDIM Command
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The QDIM Command
 The
QDIM command
 makes
chain and datum dimensioning even
easier.
 It eliminates the need to define the exact
points being dimensioned.
 Automates the process of point selection.
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The QDIM Command
 QDIM
can be selected by:
 Selecting
QDIM from the Dimension pulldown menu
 OR
 Picking
the Quick Dimension button from the
Dimension toolbar
 OR
 Typing
QDIM at the Command: prompt.
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The QDIM Command
 Single
Polyline:
 QDIM
draws linear dimensions to every
vertex.
 Single
arc or circle:
 QDIM
draws a radius or diameter dimension.
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The QDIM Command
 Multiple
Objects: QDIM draws
 Linear
dimensions to the vertex of every line
or polyline.
 Linear dimensions to the center of every arc
or circle.
 AutoCAD
finds these points automatically.
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Inserting Dimensioning Symbols
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Inserting Symbols
 After
you select a feature to dimension,
AutoCAD responds with the measurement
or dimensioning number.
 If
the object is a circle or radius, AutoCAD
automatically places the radius (R) or
diameter () symbols before the
dimension number.
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Inserting Symbols
 AutoCAD
does not place a symbol
automatically in linear dimensioning.
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Inserting Symbols
 Use
the Mtext editor to insert other
symbols.
 Place
the text cursor in the location where
you want the symbol placed
 Open
the Symbol drop-down list
 Select the symbol
 Click OK.
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Creating Your Own Symbols
 If
a needed symbol does not exist, you
can draw it and insert it on the drawing.
 It
is faster to create your own symbols,
save them as a block and insert the block
on the drawing as needed.
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The Circle Center Mark
and
DIMCEN
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Circle Center Dashes
 Circles
are dimensioned to the CENTER of
the circle.
 AutoCAD
will easily draw a centermark
that can be “dimensioned to”.
 The
command is DIMCENTER
 The mark size is set by the DIMCEN variable
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Circle Center Dashes
 To
draw the center dashes:
 Pick
the Center Mark button on the Dimension
Toolbar
 Pick Center Mark in the Dimension pull-down
menu
 Type DCE or DIMCENTER at the Command:
prompt
 When
the arc or circle is picked, the
center marks are automatically drawn.
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DIMCEN Variable
 The
DIMCEN variable controls the center
dashes.
 The
default length is 0.09” long.
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DIMCEN Variable
 If
DIMCEN = 0; center marks are not
drawn.
 If
DIMCEN < 0; AutoCAD draws
 Complete
centerlines that extend past the
edge of the circle.
 Center dashes.
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DIMCEN Variable
 If
DIMCEN > 0; AutoCAD draws
 Center
dashes ONLY.
 No extension lines outside the circle.
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DIMCEN Variable
 The
value of the DIMCEN variable sets
 The
length of the center dashes and
 The length of the extension lines past the
edge of the circle.
 DIMCEN
= 0.09. Dashes are 0.09 units long.
 DIMCEN = 0.5. Dashes are 0.5 units long.
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Summary-Dimensioning Commands
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Dimensioning Commands






DLI
DAL
DAN
DBA
DCE
DCO
DIMLINEAR
DIMALIGNED
DIMANGULAR
DIMBASELINE
DIMCENTER
DIMCONTINUE







DED
DRA
DDI
DOR
DOV
DST
LE
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DIMEDIT
DIMRADIUS
DIMDIAMETER
DIMORDINATE
DIMOVERRIDE
DIMSTYLE
LEADER
134
Using the Dimensioning Mode
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Using the Dimensioning Mode
 Entering
DIM or DIM1 enters the
“dimensioning mode”
 You
can enter as many dimensions as desired
in this mode
 Enter E or EXIT or press the [Esc] key to exit
this mode
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Dimensioning Circles
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Dimensioning Circles
 Circles
are normally dimensioned by giving
the diameter.
 Per
ASME standard, arcs are dimensioned
by giving the radius.
 AutoCAD
lets you dimension a circle or an
arc by giving the diameter dimension.
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Dimensioning Circles
 Diameter
dimensions are produced by:
 Picking
the Diameter Dimension button on the
Dimension Toolbar.
 OR
 Picking
Diameter in the Dimension pull-down
menu.
 OR
 Typing
DDI or DIMDIAMTER at the
Command: prompt.
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Dimensioning Circles
 When
you use the DIMDIAMETER
command, a leader line and diameter
dimension value are attached to the cursor
when you pick the circle or arc.
 The
leader can be dragged to any desired
location and length before picking where
you want it to be placed.
 The
Mtext, Text and Angle options are
available.
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Dimensioning Holes
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141
Dimensioning Holes
 Holes
are dimensioned in the view where
they appear as circles.
 To dimension holes:
 Give
location dimensions to the center and a
leader showing the diameter.
 Use the DIMDIAMETER command to
dimension the diameter.
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Dimensioning Repetitive Features
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Dimensioning Repetitive Features
 Repetitive
features are dimensioned by:
 The
number of repetitions
 Followed by an X, a space, and the size
dimension.
 The
dimension is then connected to the
feature with a leader.
 Refer
to Figure 18-37.
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Dimensioning Arcs
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146
Dimensioning Arcs
 The
standard for dimensioning arcs is the
radius.
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Dimensioning Arcs
 Use
the DIMRADIUS command to place a
radius command by:
 Picking
the Radius Dimension button on the
Dimension toolbar.
 OR
 Picking
Radius in the Dimension pull-down
menu.
 OR
 Typing
DRA or DIMRADIUS at the Command:
prompt.
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Dimensioning Fillets and Rounds
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Dimensioning Fillets and Rounds
 Small
inside arcs are called fillets
 Fillets
are designed to strengthen inside
corners.
 Small
arcs on outside corners are called
rounds.
 Rounds
are used to relieve sharp corners
 Dimension
each one individually as arcs or
as a general note.
 See
Figure 18-39.
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Dimensioning Angles
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Dimensioning Angles
 Coordinate
and angular dimensioning are
both acceptable for dimensioning angles.
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Dimensioning Angles
 Coordinate
dimensioning uses coordinates
to specify the length of line segments to
start locations of angles.
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Dimensioning Angles
 Angular
dimensioning
 Locates
one corner with a dimension and
provides the value of the angle in degrees.
 You can dimension the angle between any
two non-parallel lines.
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Dimensioning Curves
 Where
possible, curves are dimensioned
as arcs.
 Where curves are not of a constant-radius,
 Dimension
them to points along the curve
using the DIMLINEAR command.
 See Figure 18-40.
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Dimensioning Chamfers
A
chamfer is an angled surface used to
relieve sharp corners.
 To
dimension chamfers:
 Show
angle and a linear dimension
 OR
 Two
linear dimensions
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Transparent Dimensioning
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Transparent Commands
 Dimensioning
variables can be entered
transparently while in another command.
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Transparent Commands
 At
most dimensioning prompts, the
variable name can be entered without the
DIM prefix.
 Horizontal
 Vertical
 Aligned
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Transparent Commands

DIM: prompt
 Command:
prompt
 ALIGNED
 DIMALIGNED
 ANGULAR
 DIMANGULAR
 BASELINE
 DIMCENTER
 CONTINUE
 DIMCONTINUE
 DIAMETER
 DIMDIAMETER
 HOMETEXT
 DIMEDIT
 HORIZONTAL
 LEADER
LEADER
 NEWTEXT
Home
 DIMLINEAR
Horizontal
 DIMEDIT Text
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Transparent Commands

DIM: prompt
 OBLIQUE
 ORDINATE
 OVERRIDE
 RADIUS
 RESTORE
 ROTATED
 SAVE
 Command:
prompt
 DIMEDIT
Oblique
 DIMORDINATE
 DIMOVERRIDE
 DIMRADIUS
 DIMSTYLE Restore
 DIMLINEAR
 DIMSTYLE Save
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Transparent Commands

DIM: prompt
 Command:
prompt
 STATUS
 DIMSTYLE
 TEDIT
 DIMTEDIT
 TROTATE
 DIMEDIT
Status
 VARIABLES
Rotate
 DIMSTYLE Apply
 DIMSTYLE Variables
 VERTICAL
 DIMLINEAR
 UPDATE
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167
Transparent Commands
 Exception:
DIMCEN
 Is
interpreted as CEN object snap override if
not preceded by DIM.
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Drawing Leader Lines
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Drawing Leader Lines
 The
DIMDIAMETER and DIMRADIUS
commands automatically place leaders on
the drawing.
 The
LEADER command allows you to
begin and end a leader line where you
desire.
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Drawing Leader Lines
 Leader
lines are ideal for:
 Adding
specific notes to a drawing.
 Situations where a leader line must be
staggered to go around other drawing
features.
 Where a double leader line is required.
 Where custom leaders are needed.
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LEADER Command
 The
leader line characteristics, such as
arrowhead size and text positioning are
controlled by the dimension variable
settings.
 Other
features are controlled by options
within the LEADER command.
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LEADER Command
 The
LEADER command is accessed by:
 Picking
the Leader button in the Dimension
Toolbar.
 OR
 Picking
Leader in the Dimension pull-down
menu.
 OR
 Typing
LE or LEADER at the Command:
prompt.
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LEADER Command
 The
LEADER command prompts look like
the LINE command prompts.
 Pick
the starting and ending points of the
leader.
 The Annotation option is the default.
 Press [Enter] and type in the desired note.
 The Mtext prompt appears.
 Type as many lines of text as desired.
 Terminate with the [Enter] key.
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LEADER Command Options
 The
Annotation sub-options
 Tolerance.
 Copy.
 Block.
 None.
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LEADER Command Options
 The
Annotation sub-options
 Tolerance
 Allows
creation of the feature control frame
 Discussed in Chapter 21 of text.
 Copy
 Copies
text, mtext, feature control frame or block,
and connects the new object to the leader being
created.
 Refer to Figure 18-43B.
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LEADER Command Options
 The
Annotation sub-options
 Block
 Inserts
a specified block at the end of the leader.
 None
 This
option ends the leader with no annotations of
any kind.
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LEADER Command Format Options
 The
LEADER command allows you to
modify the way a leader line is presented.
 Accomplished
by accessing the Settings
option.
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LEADER Command Format Options
 The
Settings Options:
 Spline.
 Straight.
 Arrow.
 None.
 Exit.
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The UNDO Option
 The
Undo option removes the last leader
segment that was drawn.
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Using Multiple Leaders
 Multiple
Leaders can be drawn in
AutoCAD.
 Use
the LEADER command to place the first
leader and note.
 Enter the LEADER command again and pick
the beginning of the previous leader shoulder
as the second point.
 Use the Annotation None option to terminate
the command.
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Using Multiple Leaders

1. Draw Graphics only this week (35-39)
 After
Dimension Styles lecture (next week), we will
draw dimensions.
 DO NOT Include TITLEBLOCK on assigments!
2. Dimension Graphics using dimension styles
only!!
 3. Hatching

 Required
for PULLEY assignment.
 Lecture in two weeks.
 4.
D Size border (Asgn 40)
 Insert
version
 XREF version
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Dimension Styles
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Dimension Styles
 The
appearance of dimensions is
controlled by over 70 different settings.
 Dimension Styles are saved configurations
of these 70 settings.
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Dimension Styles
 Dimension
variables are AutoCAD system
variables that help you control the way
dimensions look.
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Dimension Styles
 Create
a dimension style that has the
desired dimension appearance.
 Name
the style appropriately.
 Dimension
styles can have a family of
settings that allow you to have different
settings for each type of dimension.
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Creating Dimension Styles
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Creating Dimension Styles
 To
use dimensions most effectively
 1.
Create a dimension style
 2. Use the style to create dimensions
 3. AVOID Dimension Overrides.
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Creating Dimension Styles
 You
can customize dimension styles to
correspond to drafting standards such as:
 ASME/ANSI
 ISO
 MIL
 Architectural
 Structural
 Civil
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Creating Dimension Styles
 Dimension
Styles are created
 using
the Dimension Styles dialog box and is
selected by:
 Picking the Dimension Styles button in the
Dimension tool bar
 OR
 Picking
Dimension Style in the Format pulldown menu
 OR
 Entering
D or DDIM at the Command: prompt
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Creating Dimension Styles
 The
Dimension Style area of the
Dimension Style dialog box displays the
name of the style.
 “Standard”.
 If
additional styles exist they are accessed in
the drop-down list.
 The
“Name” text box is where you input the
dimension style name or rename an existing style.
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Creating Dimension Styles
 “New”
button
 Creates
new dimension styles
 Name
 Recognizable
 Start
name for new dimension style.
with
 You
can base new dimension style on an existing
dimension style.
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Creating Dimension Styles
 “Use
For” button
 Use
for
 All
dimensions
 Linear dimensions
 Angular dimensions
 Radial dimensions
 Diameter dimensions
 Ordinance dimensions
 Leaders
 Tolerances
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Creating Dimension Styles
 “Modify”
 Allows
button
changes to the currently selected style.
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Creating Dimension Styles
 “Override”
button
 An
OVERRIDE is a temporary change to the
current style setting.
 The
override settings are lost when any other
style is selected as “current” again!!
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Creating Dimension Styles
 “Compare”
button
 Allows
you to view the properties of two styles
side by side.
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Creating Dimension Styles
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Creating Dimension Styles The Lines and Arrows Tab
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The Lines and Arrows Tab
 Color
 ByBlock
 Individual
color
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The Lines and Arrows Tab
 Lineweight
 ByBlock
 Individual
lineweights.
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The Lines and Arrows Tab
 Extend
beyond ticks
 Only
active with tic marks.
 Allows the dimension line to extend past the
tic mark.
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The Lines and Arrows Tab
 Baseline
Spacing
 Sets
the spacing between dimension lines of
baseline dimensions.
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The Lines and Arrows Tab
 Suppress
Dim Line 1 or Dim Line 2
 Prevents
the display of either Dim Line 1 or
Dim Line 2.
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The Lines and Arrows Tab
 Extension
Lines
 Color.
 ByBlock
 Individual
color
 Lineweight.
 ByBlock
 Individual
lineweight
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The Lines and Arrows Tab
 Extension
 Extend
Lines
beyond dim lines.
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The Lines and Arrows Tab
 Extension
 Offset
Lines
from origin.
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The Lines and Arrows Tab
 Extension
Lines
 Suppress.
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The Lines and Arrows Tab
 Arrows
 Style
- Left
 Style - Right
 Leader
arrows
 Style
 Arrow
size
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The Lines and Arrows Tab
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The Lines and Arrows Tab
 Center
Mark for Circles (DIMCEN).
 None.
 Mark.
 Line.
 Size
 Negative
- lines extend outside circle
 Positive - lines do not extend outside circle.
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Creating Dimension Styles The TEXT Tab
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The Text Tab
 Text
 Style
 Text
styles currently available in drawing.
 Color
 ByBlock
 Individual
color
 Height
 0.125”
is architectural standard height.
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The Text Tab
 Text
 Fraction
A
height scale
value of 1.0 = fraction height same as text size.
 Draw
frame around text.
 Draws
a rectangle around the text.
 Distance from text is determined by “offset from
dim line value”.
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The Text Tab
 Text
Placement - Vertical
 Centered
 Default
 Dimension
text placed in gap in dimension line.
 Above
 Architectural
drafting.
 Dimension text placed ABOVE dimension line.
 Outside
 Dimension
 JIS
text placed OUTSIDE dimension.
- Japanese Industrial Standards.
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The Text Tab
 Text
Placement - Horizontal
 Centered
 Dimension
 At
Ext Line 1
 Dimension
 At
text is centered on dimension line.
text is placed at Ext Line 1.
Ext Line 2
 Dimension
text is placed at Ext Line 2.
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The Text Tab
 Text
Placement - Horizontal
 Over
Ext Line 1
 Dimension
text is placed with and over Ext Line 1.
 Not common.
 Over
Ext Line 2
 Dimension
text is placed with and over Ext Line 2.
 Not common.
 Offset
 Sets
from dim line
gap between dimension line and dimension
text.
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The Text Tab
 Text
Alignment
 Horizontal
 Draws
 Aligned
 Draws
 ISO
unidirectional dimension text.
with dimension line
aligned dimension text.
Standard
 Aligned
text when the text is between the
extension lines.
 Horizontal dimensions when the text is outside the
extension lines.
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Creating Dimension Styles The Fit Tab
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The Fit Tab
 Fit
tab controls the placement of
 Text
 Arrows.
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The Fit Tab
 Fit
tab
 Either
the text or the arrows, whichever fits
best.
 Arrows.
 Text.
 Both text and arrows.
 Always keep text between extension lines.
 Suppress arrows if they don’t fit inside the
extension lines.
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The Fit Tab
 Text
placement
 Beside
the dimension line.
 Over the dimension line, with a leader.
 Over the dimension line, without a leader.
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The Fit Tab
 Scale
for Dimension Features
 Used
to set the scale factor for all dimension
features in the entire drawing.
 Scale
dimensions to layout (paper space)
 Sets
overall scale to adjust to active paper space
viewport, by setting the scale equal to the viewport
scale factor.
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The Fit Tab
 Fine
tuning
 Allows
maximum flexibility for placing
dimension text.
 Place
text manually
 Allows
control over text placement and dimension
line length outside dimension lines.
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The Fit Tab
 Fine
tuning
 Allows
maximum flexibility for placing
dimension text.
 Always
draw dim line between ext lines
 Forces
a dimension line inside extension lines,
even if the arrows and text are outside the
extension lines.
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The Primary Units Tab
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Primary Units Tab
 Primary
Units Tab
 Unit
Format
 Precision
 Fraction Format
 Decimal Separator
 Round off
 Prefix
 Suffix
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Primary Units Tab
 Primary
 Unit
Units Tab
Format
 Scientific
 Decimal
 Engineering
 Architectural
 Fractional
 Windows
Desktop
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Primary Units Tab
 Primary
 Unit
Units Tab
Format
 Decimal
Decimal inches
 Decimal millimeters
 Normally used on mechanical drawings for
manufacturing.
 Initial precision is four decimal places.

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Primary Units Tab
 Primary
 Unit
Units Tab
Format
 Engineering
Civil (maps, plot plans, etc.
 Initial precision - four decimal places

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Primary Units Tab
 Primary
 Unit
Units Tab
Format
 Architectural
Feet, inches and fractional inches
 Initial precision - 1/16 inch

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Primary Units Tab
 Primary
 Unit
Units Tab
Format
 Fractional
 Scientific
Very large or very small values
 Initial precision - four decimal places.

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Primary Units Tab
 Primary
Units Tab
 Precision
 How
many zeroes follow the decimal place.
 Fraction
Format
 Diagonal
 Horizontal
 Not
Stacked (Architectural only)
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Primary Units Tab
 Primary
Units Tab
 Decimal
Separator
 Commas
 Periods
(default)
 Spaces
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Primary Units Tab
 Primary
 Round
Units Tab
off
 Default
= zero (no rounding)
 0.1 = rounded to nearest 0.1
 1.188 = 1.2
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Primary Units Tab
 Primary
Units Tab
 Prefix
 Special
notes or symbols placed in front of the
dimension text.
 Example: SR3.5 (Spherical radius)
 Suffix
 Special
notes or symbols placed after the
dimension text.
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Primary Units Tab
 Measurement
Scale
 If
value = 1, dimension values are displayed
the same as they are measured.
 If
value = 2, dimension values are displayed
twice as much as they are measured.
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Primary Units Tab
 Measurement
 Apply
Scale
to layout dimensions only.
 Makes
the linear scale factor active only when
dimensioning in a layout tab.
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Primary Units Tab
 Measurement
 Zero
Scale
suppression
 Leading
On by default
 Leaves a zero on dimension numbers less than one.

 Trailing
Off by default
 Leaves zeroes after the decimal point based on the
precision setting.

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Primary Units Tab
 Measurement
 Zero
0
Scale
suppression
feet
On by default
 Removes the zero in feet and inch dimensions when
there are zero feet.

0
inches
On by default
 Removes the zero when the inch part of feet and inch
dimensions is less than one inch.

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Overriding Dimensioning Variables
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Overriding Existing Dimensioning Variables
 You
can alter dimensioning variables to
modify one or more specify dimensions on
the drawing.
Command: DOV or DIMOVERRIDE
Dimension variable to override or Clear to
remove overrides): DIMEXO
Current Value <0.062> New value: 0
Dimension variable to override: (type another
variable name to override or press [Enter])
Select objects:
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Overriding Existing Dimensioning Variables
 The
variable changes on as many
dimensions as you pick.
 You
can also clear any previous overrides
by using the Clear option.
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Dimensioning Variables
 AutoCAD
uses variables to modify the
appearance of dimensions.
 AutoCAD
has 72 (!) variables associated
with dimensions.
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Dimensioning Variables
 By
using dimension styles, you can pre-set
many of these variables.
 Use
different dimension styles to create
different types of dimensions.
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