Engineering 1182 Dimensioning Fundamentals Chapter 15 of Text

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 • Engineering 1182 Dimensioning Fundamentals Chapter 15 of Text College of Engineering Education

• Engineering 1182 Dimensioning Fundamentals Chapter 15 of Text College of Engineering Education Innovation Center

 • Engineering 1182 Objectives • Learn the basic rules for good dimensioning •

• Engineering 1182 Objectives • Learn the basic rules for good dimensioning • Be able to correctly dimension engineering drawings v. Note: There are many rules and guidelines for proper dimensioning. This module will highlight the main topics covered in Chapter 15 of the text.

 • Engineering 1182 Basic Dimensioning • Dimensioning is used to define an object

• Engineering 1182 Basic Dimensioning • Dimensioning is used to define an object so that it could be produced – Define the size and location of the features of the part. • This module will provide basic guidelines for good dimensioning practice.

 • Engineering 1182 Rule 1: Appropriate View Each dimension should be placed in

• Engineering 1182 Rule 1: Appropriate View Each dimension should be placed in a descriptive or characteristic view without dimensioning to hidden lines Rev: 20120913, AJP Presentation Short Title 4

 • Engineering 1182 Rule 2: Clarity Dimensions should be located outside the boundaries

• Engineering 1182 Rule 2: Clarity Dimensions should be located outside the boundaries of the object whenever possible and should be spaced far enough apart to be read clearly v Note: Smaller dimensions are always located closer to the object than larger dimensions. Rev: 20120913, AJP Presentation Short Title 5

 • Engineering 1182 Rule 3: Location of Dimensions that are shared between two

• Engineering 1182 Rule 3: Location of Dimensions that are shared between two views should be located between those views Rev: 20120913, AJP Presentation Short Title 6

 • Engineering 1182 Rule 4: Cylinders • Positive cylinder (e. g. a rod)

• Engineering 1182 Rule 4: Cylinders • Positive cylinder (e. g. a rod) – dimension in a view where the side of the cylinder appears as a rectangle. • Negative cylinder (e. g. a hole) – dimension in the view where the cylinder appears as a circle. • A diameter symbol is always required before a numerical value. Rev: 20120913, AJP Presentation Short Title 7

 • Engineering 1182 Rule 5: Amount of Dimensions Do not over-dimension or under-dimension

• Engineering 1182 Rule 5: Amount of Dimensions Do not over-dimension or under-dimension an object Rev: 20120913, AJP Presentation Short Title 8

 • Engineering 1182 Baseline versus Chain Dimensioning • There are many ways to

• Engineering 1182 Baseline versus Chain Dimensioning • There are many ways to use dimensions to locate features. The two basic dimensioning techniques are baseline and chain dimensioning • Both techniques are acceptable, however baseline dimensions are preferred. Baseline Dimensioning Chain Dimensioning

 • Engineering 1182 Circles and Arcs Hole and Arc Details • • Circular

• Engineering 1182 Circles and Arcs Hole and Arc Details • • Circular features of 360° - include ø the diameter symbol followed by a numerical value, e. g. ø 5. 0 Circular features of < 360° - include R the radius symbol followed by a numerical value, e. g. R 5. 0 A centermark represents the center of an arc or circle and is used for dimensioning feature locations Centerlines are used in the view where the circular feature appears as a rectangle Symmetry When symmetry is used to reduce complexity a note must be added Options include: Symmetrical from left to right, front to back, top to bottom Rev: 20120913, AJP Presentation Short Title 10

 • Engineering 1182 Dimensioning Fundamentals • Use this time to practice proper dimensioning.

• Engineering 1182 Dimensioning Fundamentals • Use this time to practice proper dimensioning. • In class activity