### Chapter 2x

```Sketching and Lettering
 Arcs
 Axis (axes)
 Composition
 Concentric Circles
 Ellipses
 Gothic Lettering
 Guidelines
 Isometric Lines
 Isometric Sketching
 Lettering
 Line
 Non- Isometric Lines
 Oblique Sketch
 Overlay
 Plane
 Point
 Proportion
 Tangent arcs
 Texture
**** YOU SHOULD WRITE THESE DOWN and
Define them.... Might be on a test!
 The
Design Process
 The
Design Process
 STEP
1: Identify the Problem -Students should state the challenge
problem in their own words. Example:
How can I design a __________ that will
__________?
 The
Design Process
STEP 2: Identify Criteria and Constraints -Students should specify the design requirements
(criteria).
Example: Our growth chamber must have a
growing surface of 10 square feet and have a
delivery volume of 3 cubic feet or less. Students
should list the limits on the design due to
available resources and the environment
(constraints). Example: Our growth chamber
must be accessible to astronauts without the
need for leaving the spacecraft.
 The
Design Process
STEP 3: Brainstorm Possible Solutions -Each student in the group should sketch his
or her own ideas as the group discusses
ways to solve the problem. Labels and
arrows should be included to identify parts
and how they might move. These drawings
should be quick and brief.
 The
Design Process
STEP 4: Generate Ideas -- In this step, each
student should develop two or three ideas more
thoroughly. Students should create new drawings
that are orthographic projections (multiple views
showing the top, front and one side) and
isometric drawings (three-dimensional
depiction). These are to be drawn neatly, using
rulers to draw straight lines and to make parts
proportional. Parts and measurements should be
labeled clearly.
 The
Design Process
STEP 5: Explore Possibilities -- The
developed ideas should be shared and
discussed among the team members.
Students should record pros and cons of
each design idea directly on the paper
next to the drawings.
 The
Design Process
STEP 6: Select an Approach -- Students
should work in teams and identify the
design that appears to solve the problem
the best. Students should write a
statement that describes why they chose
the solution. This should include some
reference to the criteria and constraints
identified above.
 The
Design Process
STEP 7: Build a Model or Prototype -Students will construct a full-size or scale
model based on their drawings. The
teacher will help identify and acquire
appropriate modeling materials and
tools. See the design brief for a sample
list.
 The
Design Process
STEP 8: Refine the Design -- Students will
examine and evaluate their prototypes or
designs based on the criteria and
constraints. Groups may enlist students
from other groups to review the solution
and help identify changes that need to be
made. Based on criteria and constraints,
teams must identify any problems and
proposed solutions.
 What
is spatial visualization?
 Isometric Drawings
 Sketching Isometric Drawings
 Coded Plans
 Visualization of Object
 Viewpoints
 Examples
 The
ability to mentally manipulate, rotate,
twist, or invert a pictorially presented
object.
 Important skill for scientific & technical
fields, such as:
• Architects & Engineers
• Doctors
• Computer Programmers
• Anyone needing a creative solution to a problem
 Sketching
is drawing freehand without the
aid of any drafting equipment except
paper and pencil. It is a very common
form of visual communication that is used
in virtually ALL areas of work and life.
1. Uses no drafting equipment - freehand
 2. Is an extremely fast form of visual
communication.
 3. Sketches increase clarity and understanding of
concepts, shapes, or directions.
 4. Is very convenient - can be done anywhere.
 5. Is an extremely valuable organizational tool,
which helps to minimize or prevent errors.
 6. Is a collection of all necessary information
required about an object - including detail, size
and shape descriptions.

 Critical
Factors
• A. Key Reasons for Sketching
1) Communicate
2) Organize
3) Realize Ideas
• B. Key Factors while Sketching
1) Speed
2) Accuracy
3) Clarity
Construction Lines to Object Lines
1) ALL single lines - NO "fuzzy" art type
lines!
2) Point to Point
3) Dash to Dash
4) Draw Left to Right OR Bottom to Top B.
Block Technique
1) Establish outer proportions of object(s)
2) Divide into areas of major shapes
4) Add text where necessary to clarify
(notes or
dimensions)
Graph Technique (Resizing or Duplicating an
Original)
1) Use original photo or drawing OR a xerox copy.
2) Draw Horizontal & Vertical grid lines on top of
object spaced an exact distance apart (ex. ½",
¼", etc.).
3) On clean sheet of paper reproduce grid at
desired size (enlarge / reduce)
4) Add line detail a block at a time.
One View Orthographic Projection
1) Always that view which would be considered the
front of the object.
2) Used when only one view is necessary to provide
shape description.
Two View Orthographic Projection
1) Front View and Top View.
2) Used for cylindrical objects when all side views
are identical.
Three View Orthographic Projection
1) Front View, Top View, and Right Side View
2) Provides the most complete shape and size
description.
3) Is the industry standard for the manufacture of
objects.
Enlargement / Reduction (Templates)
1) Use of graph paper to enlarge or reduce grid
size
2) Complete sketch square by square, comparing
individual squares as you proceed.
Realize Ideas / Designing
1) Front View, Top View, and Right Side View
2) Clarity is essential, use text notes whenever
necessary.
3) Be sure finished sketch reflects what is in your
mind.
 The
Glass BOX!
• Does it exist?
• If it does….
 How does it work?
 What’s it purpose?
 The
Glass BOX!
• Does it exist? YES
• If it does….
 How does it work? You will see….on next slide
 What’s it purpose? TO Help one visualize all the views
for an object.
 Imagine
that you have an object
inside a glass box.
 Then
draw the object on each of three
faces as seen from that direction. Unfold
the box (figure 4) and you have the
three views. We call this an
"orthographic" or "multiview" drawing.
 Figure
5 shows how the three views
appear on a piece of paper after
unfolding the box.
 Which
views should one choose for a
multiview drawing?
 The views that reveal every detail about the
object. Three views are not always
necessary; we need only as many views as
are required to describe the object fully.
 For
example, some objects need only
two views, while others need four. The
circular object in figure 6 requires only
two views.
Figure 6 An object
needing
only two
orthogonal
views
 Shows
the faces of an object
 Faces are parallel to the viewing plane
• Frontal
• Profile
• Horizontal
 Front
view shows height & width
 Side view shows height & depth
 Top view shows width & depth
 Visible edges are solid lines.
 Non-visible edges are dashed
(hidden) lines
 Views align with each other
 Rotation from one view to another
equals 90°
A
Pictorial Sketch is a picturelike sketch
in which the width, height, and depth of a
object are shown in one view.
A
Pictorial Sketch is a picturelike sketch
in which the width, height, and depth of a
object are shown in one view.
• An oblique sketch is a type of pictorial sketch in
which two of the axes are at right angles (90
degrees) to each other.
A
Pictorial Sketch is a picturelike sketch
in which the width, height, and depth of a
object are shown in one view.
• An oblique sketch is a type of pictorial sketch in
which two of the axes are at right angles (90
degrees) to each other.
A
Pictorial Sketch is a picturelike sketch
in which the width, height, and depth of a
object are shown in one view.
• An oblique sketch is a type of pictorial sketch in
which two of the axes are at right angles (90
degrees) to each other.
• An isometric sketch is a type of pictorial sketch
that relies on three axes to show width height
and depth. However , an isometric sketch, shows
the axes spaced equally. (120 degrees)
A
Pictorial Sketch is a picturelike sketch
in which the width, height, and depth of a
object are shown in one view.
• An oblique sketch is a type of pictorial sketch in
which two of the axes are at right angles (90
degrees) to each other.
 Used
to show 3-Dimensional projection
on a 2-Dimensional surface.
 Projected so that width and length are
30° from horizontal and height is vertical.
 Shows
height of each “cube” stack.
 Each corner could be a viewpoint of the
object.
 Viewpoint means the direction in which
an observer is viewing the object.
 Similar to a top view in an Orthographic
Projection.
2
1
V = Viewpoint
1
V
FOR SKECTHING –
DO NOT SHOW EACH
CUBE. SHOW ONLY
VISIBLE SURFACES
AND EDGES, AS IF
CUBES HAVE BEEN
COMBINED.
V
2
1
V = Viewpoint
1
V
Note location of
viewpoint and coded
plan noting height of
object. Click to start
animation.
V
2
2
1
1
3
V
Click to start animation.
 Viewpoints
can make the object appear
differently.
 Example #2 is redrawn with a different
viewpoint.
2
2
1
1
3
V
Click to start animation.
 Different
look
 Optical illusion of height
 Viewpoints can show or exclude details
V
2
2
1
1
3
2
2
1
1
3
V
ISOMETRIC DRAWING
ORTHOGRAPHIC DRAWING
 Spatial Visualization
is an important skill
object
 Viewpoints change look of object and
can hide details
 Sketches
are not usually made to scale
(exact measurement).
• It is important to still show proportions, so that
each part of the drawing is roughly the right size
in relation to other parts of the drawing.
 First
what is a dimension?
• Dimensioning is a way of enhancing the shape
description provided by the drawing. By
dimensioning the drawing, you are providing a
size description to enhance the shape
description provided.
 When
dimensioning a drawing, the
drafter must keep in mind the final
object. Therefore, all information must be
included such as sizes and the processes
required to make the final piece.
 All
drawings must be made to scale, with
that scale indicated either in the title
block, or below the detail's title on the
sheet.
 There
are many standards or "rules" for
dimensioning a drawing. These may
differ depending on the type of drawing
and the accepted business standards for
that discipline.
 Rough
Sketch
 Refined Sketch
 Presentation Sketch
 Temporary Sketch
 Permanent Sketch
 The Overlay
 Paper
and Pencil
ISO A Drawing Sizes
(mm)
A4
210 X 297
A3
297 X 420
A2
420 X 594
A1
594 X 841
A0
841 X 1189
U.S. Customary
Drawing Sizes
A
8.5" X 11"
B
11" X 17"
C
17" X 22"
D
22" X 34"
E
34" X 44"
9H 8H 7H 6H 5H 4H 3H 2H H
Hardest
→
F
Medium
H
B
B
2B 3B 4B 5B 6B 7B 8B 9B
→
Softest
Tone
U.S.
#1
#2
#2½ *
#3
#4
World
B
HB
F
H
 Lettering
is used on drawings to give
dimensions and other pertinent information
needed to fully describe the item.
 The lettering must be neat and legible if it is to
A
drawing will be improved by good
lettering.
 However, a good drawing will look
sloppy and unprofessional if the lettering
is poorly done.

The American National Standards Institute (ANSI)
recommends that the Single-Stroke Gothic Alphabet be
the accepted lettering standard

It can be drawn rapidly and is highly legible because each
part of every letter is made by a single stroke.

This is because there are no serifs on the letters of this
alphabet.
• A serif is like a tiny foot on a letter; alphabets that have serifs
are more difficult to letter by hand. An alphabet without serifs
is always called a san serif alphabet.

Today, because of computers,
there are many different
alphabet styles (also called
fonts).
• When lettering a drawing, if the
single stroke Gothic alphabet is
not available, choose a san serif
font and use only upper case
letters.

Use guide lines
• Guide lines should be drawn so lightly they will not show up
on a print made from the drawing
• Vertical guide lines may be used to assure that the letters will
be vertical
• Inclined guide lines are drawn at 67 1/20 to the horizontal line
when inclined lettering is to be used.
INCLINED GUIDE LINES HELP KEEP
INCLINED LETTERING UNIFORM

Only one form of lettering should appear on a drawing.
AVOID COMbINING
SEVERAL fORMS
Of LETTERING.

Spacing:
• Proper spacing of the letters is important.
• The letters should be placed so spaces between the letters
appear to be about the same.
SPACED VISUALLY
SPACED BY MEASURING
altering existing designs or creating
something brand new is always a
challenging task. However, if we can
follow a process or a plan, we can often
times shorten the time required to
complete the project as well as ensure
that we have not missed any necessary
elements or crucial steps.

 Using any available source, research and then write a one
page summary / explanation of "the design process." Be sure
to include the recommended steps that should be followed.
 Use the design process to create a new or original product
 Create 'several' brainstorming sketches as you attempt to
work out the final version of your product
 Sketch a FINAL three view orthographic projection of your
finished design. Be sure to include a title and as much detail
(and labels) as necessary to communicate your idea to
another person.
 Self evaluate...
 Staple your papers (Research report, Brainstorming sketches
& Final sketch) together and turn in.

Assignments starting Page 58
Problems 1, 3, 6, 9,10
Due in ONE WEEK
Complete on Graph paper
```