Introduction to Engineering Dimensioning - 2

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Introduction to EngineeringDimensioning - 2

• Agenda
• Understand the principles of good dimensioning
  practice
• Apply the standard dimensioning practices for
  mechanical drawings

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Dimensioning

• Orthographic and isometric views define the shape
  and general features of the object
• Dimensioning adds information that specifies
• Size of the object
• Location of features (e.g. holes)
• Characteristics of features (e.g. depth and
  diameter of hole)
• Dimensions also communicate the Tolerance (or
  accuracy) required

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Dimensions include notes for construction or
manufacturing

• Type of material to use
• How smooth or rough the surface should be
• Etc

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Standards for Dimensioning

• Defined Standards have been developed
• Available from ANSI
• American National Standards Institute

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Scaling vs. Dimensioning

• Drawings can be of different scales, but
  dimensions are ALWAYS at full scale.

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Dimensioning - Terminology
(Study 4.2.1 and 4.2.2 of text, carefully)
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Dimensioning - Text Height and Standard
Configurations
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Dimensioning Basic Shapes -Assumptions

• Perpendicularity
• Symmetry

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Dimensioning Basic Shapes -Simple Shapes

• Rectangular Prism (Principal Dimensions H,W,D)

D
W
H
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Video on Dimensioning
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Assignment

• Drawing 2