1

Introduction to EngineeringDimensioning - 2

Agenda Understand the principles of good

dimensioning practice Apply the standard dimensioning practices for

mechanical drawings

2

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

3

Dimensions include notes for construction or manufacturing

Type of material to useHow smooth or rough the surface

should beEtc…

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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

.25 in

.375 in

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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