1. 2D Essentials
Instructor: Laura Gerold, PE
Catalog #10614113
{ Class # 22784, 24113, 24136, & 24138
Class Start: January 18, 2012 Class End:
May 16, 2012

2. Questions . . .

3. When do you include the
projection angle symbol
on plans?
 When you are working on plans that will be
used in Europe or Asia.

4. ELLIPSE TEMPLATES
These ellipse guides are usually designated by the ellipse angle, the
angle at which a circle is viewed to appear as an ellipse.

5. DRAWING A FOCI ELLIPSE
 Major axis = long axis of ellipse
 Minor axis = short axis of ellipse
 The foci of the ellipse are two special points E and F on
the ellipse's major axis and are equidistant from the
center point. The sum of the distances from any point P
on the ellipse to those two foci is constant and equal to
the major axis ( PE + PF2= 2A ). Each of these two points
is called a focus of the ellipse.

6. DRAWING A FOCI ELLIPSE
 Let AB be the major axis and CD the minor axis
 To find foci E and F, draw arcs R with radius equal to half the major
axis and centers at the end of the minor axis
 Between E and O on the major axis, mark at random a number of
points.
 Using a random point (point 3), with E and F as centers and radii A-3
and B-3, draw arcs to intersect at four points 3’. Use the remaining
points to find four additional points on the ellipse in the same
manner.
 Sketch the ellipse lightly through the points

7. Drawing an Ellipse
 Draw a major axis 5” long and a minor axis 2.5” long.
Draw an ellipse by the foci method with at least five
points in each quadrant

8. DRAWING AN ARC TANGENT TO TWO
LINES AT ACUTE OROBTUSE ANGLES
 Given two lines not making a 90°
 Draw lines parallel to the given lines at distance R from them to
intersect at C the center
 From C, drop perpendiculars to the given lines to locate tangent
points, T
 With C as the center and with given radius R, draw the required
tangent arc between the points of tangency

9. DRAWING AN ARC TANGENT TO TWO
LINES AT ACUTE OROBTUSE ANGLES
 Draw two intersecting lines at an acute
angle, each 2.5 inches long
 Draw a 1.5 inch radius arc tangent to the
two lines

10. TEST REVIEW
{

11. How Many Questions are
on the Test?
50
You have the entire class
period to complete the test

12. How are the questions
formatted?
 True and False
 Multiple Choice
 Fill in the Blank
 Essay Questions
 Drawing

13. What can I bring?
 All of your drawing utensils
 A Calculator
 This is NOT an open book exam.
 Other electronic devices can not be used
in place of a calculator

14. What do I need to know
how to draw?
 Circles
 Squares
 Bisect an angle
 Perpendicular Bisect a line
 Triangles
 Orthographic Sketches
 Alphabet of Lines
 Lettering

15. What Chapters in the
Book Will be Covered?
 Chapter 1
 Chapter 2
 Chapter 3 (Sections 1-5)
 Chapter 4
 Chapter 5

16. What Should I Use to
Study?
 Class Notes (Power Points on Blackboard)
 Class Notes you took
 Homework
 Textbook

17. Potential Topics on Test
 Identify and Describe the five phases of the design
process
 Identify what technical drawings are used for
 Identify why drawing by hand is still useful
 Identify who creates technical drawings and what
professions use them
 Draw & Identify the Alphabet of Lines

18. Potential Topics on Test
 Apply civil engineering scales to sketches of simple
objects
 Apply architectural scales to sketches of simple
objects
 Scale a drawing up or down using scale ratios (ex
1:2, 2:1)
 Apply standard lettering practice and standards to
sketches
 Identify negative space

19. Potential Topics on Test
 Describe Prisms
 Describe Cylinders
 Describe Pyramids
 Describe Cones
 Describe Spheres
 Describe a Torus
 Describe Ellipsoids

20. Potential Topics on Test
 Describe Parallelograms
 Describe a Trapezoid
 Describe a Trapezium
 Describe a Regular Polygon up to 8 Sides
 Describe a Circumference of a Circle
 Describe Diameter of a Circle
 Describe Radius of a Circle
 Describe a Quadrant of a Circle
 Describe a Chord of a Circle
 Describe Concentric Circles
 Describe Eccentric Circles
 Identify the point at which a line is tangent to an arc
 Identify the pint at which an arc is tangent to an arc

21. Potential Topics on Test
 Differentiate between the 1st and 3rd Angle
Projection
 Name and position the 6 primary views
 Create orthographic sketches of simple objects
 Transfer dimensions
 Apply hidden line conventions to sketches
 Apply line precedence conventions to sketches

22. What are you confused
about?
 Write down a question that you still have about a
topic that will be covered on the test.
 Share the question and topic with your group
 As a group determine the answer to the question
 Still stumped? Ask a neighboring group
 Classroom stumped? Save the question for the end
and ask me

23. Stand up and Stretch . . .
It’s time for a review
game!

24. Information Domination
 Which Team Will Dominate? Winning team will each receive 5
extra credit points.
 Pick a team name
 Team members pick a category and answer the next question in
that category
 All question are answered in order starting with 1 then 2, etc.
 If the team answers correctly, they get 2 points
 If they have to use their text to answer, they only get 1 point
 If nobody on the team is able to answer the question correctly,
they can say “pass.” The next team gets a chance to answer for 1
point.

25. Information Domination
 Design Process 1, 2, 3, 4, 5
 Alphabet of Lines 1, 2, 3, 4, 5, 6
 Scales 1, 2, 3, 4, 5
 Lettering 1, 2, 3, 4
 Solids 1, 2, 3, 4, 5, 6, 7, 8
 Planar Shapes 1, 2, 3, 4, 5, 6, 7, 8, 9, 10
 Orthographic Sketches 1, 2, 3, 4, 5, 6, 7, 8

26. Ready for the Test??
{ Any additional questions??

27. Chapter 5 –
ORTHOGRAPHIC
PROJECTION
{

28. VIEWS OF SURFACES
There are terms used for describing a surface’s orientation to the plane of
projection. The three orientations that a plane surface can have to the plane
of projection are normal, inclined, and oblique.
Note how a plane surface
that is perpendicular to a
plane of projection
appears on edge as a
straight line

29. Wisconsin House Hotel –
Normal Surfaces

30. Normal Surfaces
 A normal surface is parallel to the plane of
projection
 It appears its true shape and size on orthographic
drawings.
 A edges are true length on plane of projection

31. “Normal” Group Project
 Use your blocks to make a creation
different than last week
 Sketch the three necessary views

32. Heritage Hill – Inclined
Surfaces

33. Inclined Surfaces
 An inclined surface is perpendicular to one plane of
projection
 It is inclined or tipped to adjacent planes
 Inclined edge is parallel to one plane of projection and
appears true length on this plan (appears as angled line)
 Inclined edge appears as a foreshortened line on adjacent
planes (appears as horizontal or vertical line)

34. “Inclined” Group Project
 Each group gets a right triangular prism
 Draw the three necessary views
 What was different about drawing the inclined planes
versus the normal planes (with the blocks)?

35. Milwaukee Art Museum –
Oblique Surfaces

36. Oblique Surfaces
 An oblique surface is tipped on all principal planes of
projections
 It does not appear on edge or true size in any standard
view
 An oblique edge appears foreshortened and at an angle in
every view

37. “Oblique” Group Project
 As a group, try to think of any oblique surfaces
you have seen at home, work, or on your way
here tonight.
 Sketch up a few and present to class

38. ANGLES
If an angle is in a normal plane (a plane parallel to a plane of projection) it will
show true size on the plane of projection to which it is parallel.

39. Chapter 6 – 2D Drawing
Representation
{

40. Conventional Representations
Standard orthographic projections
don’t always show complex shapes as
clearly and simply as you may wish,
so certain alternative practices,
referred to as conventions, are
accepted.
Conventions are like rules for breaking
the rules. Note how these views are
projected
What do you notice on these
drawings?
Orthographic Views of Intersecting
and Tangent Surfaces.
(Lockhart, Shawna D.; Johnson, Cindy M., Engineering Design
Communication: Conveying DesignThrough Graphics, 1st, ©
2000. Printed and Electronically reproduced by permission of
Pearson Education, Inc., Upper Saddle River, New Jersey.)

41. Removed Views
 Can’t always show all views on a
sheet
 When this is the case, use a
removed view
 Two ways to show this. . .

42. Removed Views – Type 1
Use a View Indicator arrow to show direction of sight

43. Removed Views – Type 2
Use a Viewing Plane Line

44. Group Project – Removed
Views
 Remove a View from one of your group
drawings of today
 Create a removed view plane using an
indicator arrow or viewing plane line

45. Manufactured
Features
• Fillet
• Round
• Counterbore
• Countersink
• Spotface
• Boss
• Lug
• Flange
• Chamfer
• Neck
• Keyway/Keyseat
• Knurl
• Bushing

46. Manufactured Features
For class on March 21st,
bring in objects with
“manufactured features”
for use in group projects

47. Review of Drafting
 Overview of Drafting

48. What’s Next?
• Test next week – March 7th
• Spring Break March 14th - NO CLASS
• Finish Chapter 6 – 2D Drawing Representation
on March 21st

49.  On one of your sketches, answer the
following two questions:
 What was the most useful thing that you
learned today?
 What do you still have questions about?
Questions?

50. Chapter 5 Review Question: 5
Chapter 5 Exercises: 5.2, 5.5 (9), 5.6 (8– no
isometric drawing)
Homework – Due March
21st!