1 Introduction to Engineering Dimensioning - 1 Goals Understand units and measures Understand concepts of scaling and types of scales Turn in Lab 2 report

2 Review 1 st Semester Oriented toward drawing Learned the concept of sketching and projections – isometric and multi-view Learned the concepts of section views Learned how to achieve the above concepts in CAD 2 nd Semester Focus on detailing the sketches – dimensions, tolerancing and working drawings

3 Units of Measure Measurement of Length and angle are used in Engineering Graphics Length  English - Inches, unless otherwise stated Up to 72 inches – feet and inches over  SI – millimeter, mm Angle (angular measurements)  Degrees, minutes, seconds (60° 30’ 20”)  Degrees in decimal (60.53°)

4 Terms and definitions - Scaling Scaling a drawing is a process for making an object fit the dimensions of the display media (e.g. paper) Scales are tools used to scale a drawing while creating it – a conversion factor

5 Three Common Types (Labels) for Scales More on length measurements

6 Types of Scales by Presentation Open-divided Full-divided More on length measurements

7 Types of Scales (Tools) by Construction More on length measurements

8 Architect’s Scale – Major Unit = 1 foot Divisions = inches Civil Eng. Scale – Major Unit 1 inch = 10’s of feet Divisions = tenths Mech. Eng. Scale – Major Unit = 1 inch Divisions = fraction of an inch

9 Example Use – Architect’s Scale

10 Example Use – Mechanical Engineer’s Scale

11 Your Scale

12 DWG1: Practice with scales Assignment sheets provided in your course packet (labeled DWG 1A, 1B and 1C Assignment sheets provide example solutions