This document introduces different types of dimensions used in engineering drawings. It discusses length, height, depth and breadth dimensions as well as angular and radii dimensions. Examples are given of drawing a box with height and width dimensions and dimensioning a drawing of an iPod. Readers are challenged to draw and dimension Pac-Man and other round characters while practicing different types of dimensions. Scaling drawings proportionally is also introduced.

1. INTRODUCTION TO
TECHNOLOGY
Pre-Engineering/Design/STEM 

2. OVERVIEW
• What are dimensions
• Types of Dimension
• How to use a ruler
• Activity

3. WHAT IS A DIMENSION
• Dimension = A
measurement. It can be a
length, height, depth,
breadth
• Normally measured using
the metric system (cm or
mm) or inches/feet

4. WHAT IS A DIMENSION
• This is one type of
measurement it has:
– lines extending from where its
measuring from
– Arrows the show you the
length/angle of measurement
– The actual length

5. WHAT IS A DIMENSION
• Using a ruler, draw a box
that is 5” high and 2” wide.
Make sure you give it two
dimension.
5
2

6. TYPES OF DIMENSION
• DATUM dimensions, from one
point to another point to give a
basic measurement. Here are
different ways to do them

7. DIMENSION CHALLENGE
• Looking at the dimensioned iPod
picture on the right. Using a ruler,
make your own iPod of the same
height and length (don’t worry
about the Radius). Give it the
same dimension as well
• If its too difficult, you can scale the
drawing.

8. OVERVIEW
• What is Angular Dimensions
• What is Radii Dimensions

9. DEFINITIONS
• Angular Dimension = A measurement for
angles in a given object
– ANGULAR = Angles
• Radii Dimension = A measurement for circles,
arc, fillets, or anything rounded, as a diameter
and/or radius

10. TYPES OF ANGULAR DIMENSIONS

11. TYPES OF ANGULAR DIMENSIONS

12. TYPES OF DIMENSION

13. DIMENSION CHALLENGE
1. Draw Pac Man
– Body
– Eye
– Mouth
– Personalized extra
2. Dimension Pac Man
– Diameter or Radius
– Angular Dimension
3. Draw another round character and
dimension it example
– Kirby, Jiggly Puff, Sun, Pac Man
Ghost

14. SCALING
• Scaling is making a drawing
appear smaller or larger, but
everything is proportional.
• To scale, you take the dimensions
of a drawing, and multiply each
dimension by the same number.