1. Dimensioning Standards
Get out your notes.
Dimensioning Standards

2. Learning Objectives
Understand and be able to apply different dimensioning standards to drawings.

3. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
Dimension Guidelines
Note: There are dozens of rules, do’s and don’ts, and guidelines associated with dimensioning. This purpose of this presentation is to introduce those guidelines that are most critical, and that students tend to have the most trouble with when first learning how to dimension drawings. Each slide has notes that provide references to textbooks that give further details on each guideline.
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Copyright 2007

4. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
1. Dimensions should NOT be duplicated, or the same information given in two different ways.
Incorrect
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Copyright 2007

5. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
1. Dimensions should NOT be duplicated, or the same information given in two different ways.
References:
Pg 337 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 109 Fundamentals of Modern Drafting by Paul Wallach
Pg 425 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg 701 Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
Project Lead The Way, Inc.
Copyright 2007

6. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
2. No unnecessary dimensions should be used – only those needed to produce or inspect the part.
References:
Pg 109 Fundamentals of Modern Drafting by Paul Wallach
Pg 392 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Note: In a chain of dimensions, as seen with the width and height dimensions in the front view, one of the dimensions is unnecessary and must be removed. Overall dimensions for width, height, and depth must be present.
Incorrect
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Copyright 2007

7. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
2. No unnecessary dimensions should be used – only those needed to produce or inspect the part.
References:
Pg 109 Fundamentals of Modern Drafting by Paul Wallach
Pg 392 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Note: In a chain of dimensions, as seen with the width and height dimensions in the front view, one of the dimensions is unnecessary and must be removed. Overall dimensions for width, height, and depth must be present.
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Copyright 2007

8. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
3. Dimensions should be attached to the view that best shows the contour of the feature to be dimensioned.
References:
Pg 342 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 405 & 425 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg 698, 700, Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
It should be noted that the 2.00 inch dimension would be appropriately located if placed on the top view, but the front view is preferred because it is supposed to provide the most information about an object’s geometry.
Incorrect
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9. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
3. Dimensions should be attached to the view that best shows the contour of the feature to be dimensioned.
References:
Pg 342 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 405 & 425 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg 698, 700, Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
It should be noted that the 2.00 inch dimension would be appropriately located if placed on the top view, but the front view is preferred because it is supposed to provide the most information about an object’s geometry.
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10. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
4. Whenever possible, avoid dimensioning to hidden lines and features.
References:
Pg 342 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 134 Fundamentals of Modern Drafting by Paul Wallach
Pg 426 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg 703 Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
Incorrect
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Copyright 2007

11. 4. Whenever possible, avoid dimensioning to hidden lines and features.
Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
4. Whenever possible, avoid dimensioning to hidden lines and features.
References:
Pg 342 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 134 Fundamentals of Modern Drafting by Paul Wallach
Pg 426 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg 703 Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
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Copyright 2007

12. Incorrect 5. Avoid dimensioning over or through the object.
Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
5. Avoid dimensioning over or through the object.
Incorrect
References:
Pg 342 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 394, 404, 426 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg 692 Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
Project Lead The Way, Inc.
Copyright 2007

13. 5. Avoid dimensioning over or through the object.
Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
5. Avoid dimensioning over or through the object.
References:
Pg 342 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 394, 404, 426 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg 692 Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
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14. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
6. A dimension should be attached to only one view; for example, extension lines should not connect two views.
Reference:
Pg 426 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Incorrect
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15. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
6. A dimension should be attached to only one view; for example, extension lines should not connect two views.
Reference:
Pg 426 Technical Drawing 9th Edition by Frederick Giesecke et. al.
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16. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
7. Whenever possible, locate dimensions between adjacent views.
Incorrect
References:
Pg 342 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 108 Fundamentals of Modern Drafting by Paul Wallach
Pg 426 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Project Lead The Way, Inc.
Copyright 2007

17. 7. Whenever possible, locate dimensions between adjacent views.
Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
7. Whenever possible, locate dimensions between adjacent views.
References:
Pg 342 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 108 Fundamentals of Modern Drafting by Paul Wallach
Pg 426 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Project Lead The Way, Inc.
Copyright 2007

18. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
8. Avoid crossing extension lines, but do not break them when they do cross.
Multiple extension line crossings may be confused for the outside corner of the part.
References:
Pg 342 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 394, 426 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg 690 Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
Note: Crossing extension lines is acceptable, but excessive numbers of crossings may confuse the viewer.
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Copyright 2007

19. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
9. Whenever possible, avoid sending extension lines through object views.
Incorrect
Reference:
Pg Engineering Drawing and Design 3rd Edition by David Madsen et. al.
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Copyright 2007

20. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
9. Whenever possible, avoid sending extension lines through object views.
Reference:
Pg Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Project Lead The Way, Inc.
Copyright 2007

21. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
10. In general, a circle is dimensioned by its diameter and an arc by its radius.
References:
Pg , Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 131, Fundamentals of Modern Drafting by Paul Wallach
Pg , , 427 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg , Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
Project Lead The Way, Inc.
Copyright 2007

22. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
11. Holes are located by their centerlines, which may be extended and used as extension lines.
References:
Pg 44, 340 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg , 426 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
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Copyright 2007

23. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
12. Holes should be located and sized in the view that shows the feature as a circle.
Incorrect
References:
Pg 351 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 109 Fundamentals of Modern Drafting by Paul Wallach
Pg 411, 427 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg 693 Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
Project Lead The Way, Inc.
Copyright 2007

24. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
12. Holes should be located and sized in the view that shows the feature as a circle.
References:
Pg 351 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 109 Fundamentals of Modern Drafting by Paul Wallach
Pg 411, 427 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg 693 Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
Note: The top view was removed, because it is not needed to completely communicate the object’s geometry.
Project Lead The Way, Inc.
Copyright 2007

25. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
13. Do not cross a dimension line with an extension line, and avoid crossing dimensions with leader lines.
References:
Pg 342 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 394, 426 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Project Lead The Way, Inc.
Copyright 2007

26. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
13. Do not cross a dimension line with an extension line, and avoid crossing dimensions with leader lines.
References:
Pg 342 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 394, 426 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Project Lead The Way, Inc.
Copyright 2007

27. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
14. Leader lines point toward the center of the feature, and should not occur horizontally or vertically.
References:
Pg 45, 344 Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg , , 426 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg , 703 Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
Note: Slopes greater than 75° and less than 15° from horizontal should be avoided. A leader has a .25 in shoulder at one end that begins at the center of the vertical height of the lettering and an arrowhead at the other end point.
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Copyright 2007

28. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
15. Dimension numbers should be centered between arrowheads, except when using stacked dimensions, and then the numbers should be staggered.
Incorrect
References:
Pg Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 137 Fundamentals of Modern Drafting by Paul Wallach
Pg 400, 426 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
Note: The 0.50 dimension cannot fit in between its extension lines, and is placed to the outside of the common extension line to avoid confusion.
Project Lead The Way, Inc.
Copyright 2007

29. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
15. Dimension numbers should be centered between arrowheads, except when using stacked dimensions, and then the numbers should be staggered.
References:
Pg Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 137 Fundamentals of Modern Drafting by Paul Wallach
Pg 400, 426 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
Project Lead The Way, Inc.
Copyright 2007

30. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
16. Concentric circles are dimensioned in the longitudinal view, whenever practical.
Incorrect
References:
Pg Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 407 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
Note: This rule applies to shafts, not to holes.
Project Lead The Way, Inc.
Copyright 2007

31. Dimension Guidelines
Introduction to Engineering Design
Unit 2 – Lesson 2.2 – Dimensions and Tolerances
16. Concentric circles are dimensioned in the longitudinal view, whenever practical.
References:
Pg Engineering Drawing and Design 3rd Edition by David Madsen et. al.
Pg 407 Technical Drawing 9th Edition by Frederick Giesecke et. al.
Pg Technical Graphics Communication 3rd Edition by Gary Bertoline & Eric Wiebe
Note: This rule applies to shafts, not to holes.
Project Lead The Way, Inc.
Copyright 2007

32. Dimensioning 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
ISO
MIL
DOD
CEN
DIN
JIS

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

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

35. Standards Institutions
DIN - Deutsches Institut für Normung. The German Standards Institute created many standards used worldwide, including the standards for camera film.
JIS - Japanese Industrial Standard. Created after WWII for Japanese standards.
CEN - European Standards Organization.

36. Dimension Components Dimension Line Dimension Text Arrow Head
Extension Lines

37. Dimension Text Guidelines
If the dimension text will not fit between the extension lines, it may be placed outside them

38. Dimension Text Guidelines
Dimension text is placed in the middle of the line both horizontally
and vertically

39. 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.

40. Dimensioning Methods Aligned Unidirectional
Dimensions are placed so that they can be read from the bottom of the drawing sheet. This method is commonly used in mechanical drafting.
Aligned
Dimensions are placed so the horizontal dimensions can be read from the bottom of the drawing sheet and the vertical dimensions can be read from the right side of the drawing sheet. This method is commonly used in architectural and structural drafting.

41. Classification of Dimensions
Size. Dimensions are used to identify the specific size of a feature on an object.
Location. Dimensions are used to identify the physical proximity of a feature to another feature within an object.
Size dimension
Location dimension
Location dimension
Size dimension

42. Linear Dimensioning Chain Dimensioning
Dimensioning from feature to feature
Common dimensioning technique

43. Chain Dimensioning Examples
Presentation Name
Course Name
Unit # – Lesson #.# – Lesson Name
Chain Dimensioning Examples
METHOD 1
METHOD 2
Dimension from feature to feature across entire part
Manufacturing inaccuracies can accumulate
Dimension from feature to feature except omit one partial dimension in the chain
Dimension overall length/width/height to limit manufacturing inaccuracies
Preferable chain dimensioning method
It is impossible to manufacture a part to an exact dimension. If a part is measured precisely enough, the part configuration will deviate from the specified dimensions. Typically a small amount of deviation from the specified dimension is allowed, but the error can add up in a chain of dimensions compounding the error and resulting in a part that is much smaller or larger than intended. Therefore, specifying the overall dimension (with its small allowable error in that one dimension) will reduce the deviation of the overall part size. We will talk about tolerances, the allowed deviation of a dimension on a manufactured part from the specified dimension, later in this unit.
For now, when chain dimensioning, use the preferred method (Method 2) when possible.

44. Datum Dimensioning Datum Dimensioning
Dimensioning from a single point of origin called a DATUM
Reduces dimensional deviations in manufactured parts because each size/location dimension is referenced to a single point

45. Datum Dimensioning

46. Dimensioning Symbols Presentation Name Course Name
Unit # – Lesson #.# – Lesson Name
Dimensioning Symbols
Some common dimensioning symbols.

47. 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 for distance and the angle.
Coordinate Method
Angular Method

48. Dimensioning Chamfers
Presentation Name
Course Name
Unit # – Lesson #.# – Lesson Name
Dimensioning Chamfers
Internal Chamfers
Two options for 45 degree external chamfers
Chamfers are used on outside edges to avoid sharp corners for safety and handling.
External chamfers other than 45 degrees

49. 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.

50. Dimensioning Arcs Use a capital R to indicate radius
Arrows can be inside or outside for small arcs.
Small arcs do not need center marks.
Large arcs need a center mark

51. Presentation Name
Course Name
Unit # – Lesson #.# – Lesson Name
Fillets and Rounds
Fillet. An inside radius between two intersecting planes
Round. An outside radius applied to corners
Fillet
Round
A round is used to avoid sharp edges for safety and handling. A fillet is used to provide strength at inside corners to avoid fracture. In addition fillets and rounds (as opposed to sharp corners) can make it easier to remove molded parts from molds.
Identify which arcs are fillets and which are rounds.

52. Dimensioning Circles Holes should use hole notes
Full circles should be dimensioned using the diameter
This hole note specifies a hole with a diameter and 1.00 deep

53. Cylindrical parts may be dimensioned in this manner
Dimensioning Circles
Cylindrical parts may be dimensioned in this manner
Note that the diameter symbol is used so that the dimension is not assumed to be linear

54. Dimensioning Splines and Curves
Points are placed along the contour of splines and dimensioned from a datum.
DATUM

55. Dimensioning Splines and Curves
Presentation Name
Course Name
Unit # – Lesson #.# – Lesson Name
Dimensioning Splines and Curves
This section view provides coordinate dimensions for the curvature of the windshield of the Automoblox T9 truck. We refer to these dimensions as coordinate dimensions because the horizontal and vertical distances from a given point, the datum (or origin), are given for each identified point along the curve.
DATUM

56. Reference Dimensions
“X” indicates the number of places (or occurrences)
2 X indicates that there are two identical holes

57. Dimensioning Radial Patterns
Angles and radius values are used to locate the center of radially patterned features

58. Review Datum Dimensioning Chain Dimensioning
Unidirectional dimensioning
Coordinate method
Angular Method

59. Review: Creating Drawings in CAD

60. Creating A Drawing Drawings communicate ideas
Standards define drawing properties
Inventor process
Create a part
Create a drawing
Place base view
Project views from base (multi-view and isometric)
Dimension multi-views

61. Drawing Creation Create a part (.ipt file)
Open the 7-1workingdrawingtutorialPart.ipt file

62. Drawing Creation
Create a drawing file (.idw file) from this part file.

63. Creating a Custom Drawing Tutorial
Introduction to Engineering DesignTM
Unit 2 – Lesson 2.4 – Drawing Presentation Standards
Change Sheet Size
Change sheet size to A (8.5 in. x 11in.)
Right click Sheet
Click Edit Sheet
Select A-size
Use the pull down menu to select A
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64. Creating a Custom Drawing Tutorial
Introduction to Engineering DesignTM
Unit 2 – Lesson 2.4 – Drawing Presentation Standards
Delete Title Block
Delete ANSI title block
Right click ANSI – Large
Click Delete
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65. Add Title Block Add A-size title block
Expand Drawing Resources in browser
Expand Title Blocks
Right click ANSI A
Click Insert

66. Edit Title Block Information
Presentation Name
Course Name
Unit # – Lesson #.# – Lesson Name
For this project select the summary tab and give the title.
YourName 7.1 Problem Number
Edit Title Block Information
Enter title block text
Single click Pro icon
Click iProperties
Complete fields

67. Summary Tab

68. Create Base View

69. Create Base View Click Base Select part file, orientation and scale
Click to place base view
Select Best Front View.

70. Create Base View Click Base Select part file, orientation and scale
Click to place base view
Click to change orientation
Part File
Default Orientation. Click on page to select position.
Select to shade the isometric
Select scale for best view

71. Project Views Click Projected Click where want views to be placed
Automatically Selected when part is initially placed.
Click where want views to be placed
Right Click
Click Create

72. Optional: Isometric Shading
Right click isometric view
Click Edit View
Shaded and Scale

73. Dimension Multi-View Click on Annotate Tab Click Dimension
Click reference for extension lines
Move cursor away from view
Click to place dimension
Use the standards defined in each problem.

74. Example Drawing

75. Applying the Dimensioning Standards
Complete Activity 7.1 More dimensioning
Save each piece using the convention
YourName7-1ProblemX
For Problem 6, Since the printer is not working, Evaluate your neighbors drawings and let them make appropriate corrections for 7
8: Bonus
Conclusion: Answer the questions in a Word Document using complete sentences.