1 Introduction to Engineering Dimensioning - 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 use How smooth or rough the surface should be Etc…

4 Standards for Dimensioning Defined Standards have been developed Available from ANSI  American National Standards Institute

5 Scaling vs. Dimensioning Drawings can be of different scales, but dimensions are ALWAYS at full scale.

6 Dimensioning - Terminology (Study and of text, carefully)

7 Dimensioning - Text Height and Standard Configurations.25 in.375 in

8 Dimensioning Basic Shapes -Assumptions Perpendicularity Symmetry

9 Dimensioning Basic Shapes -Simple Shapes Rectangular Prism (Principal Dimensions: H,W,D) D W H

10 Video on Dimensioning

11 Assignment Drawing #2