Engineering Drawing
Sketching Skills
GSMST
Objectives
Tips and Techniques
Lettering
Patience and practice needed
Sketching
Although most final drawings are computer
generated, initial and freehand sketches are
vital to the design process
Freehand does not mean messy. Sketches
should display an adequate amount of
detail, and any pertinent notes/comments
pertaining to the drawing
 For instance, if a line is supposed to be
straight, make it as straight as possible.
A square will not pass for a circle.
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Sketching
Sketching is a rapid, freehand method
of drawing without the use of drawing
instruments. Sketching is also a
thinking process and a method of
communication.
Sketching
This is not artistic sketching, but
technical sketching
Emphasis will be on sketching
geometric figures to represent features
of objects
Medium grade pencils work best for
sketching
All lines should be dark enough to
standout from the page
Engineering Drawing Rules
Always use a Pencil.
Make all lettering the same size.
Use Engineering or Drafting Paper.
Pencil Techniques
The best pencil for
lettering on most
surfaces are the H,
F, and HB grades.
Hold your pencil in
the position shown.
It should make
approximately a 60o
angle with the
paper.
Pencil Lead Designation
Note: Reverse order below
Sketching Tips: General
Relax and draw in a direction comfortable
to you
Mark end points of the lines to be sketched
and draw between them
Draw long lines as a series of short ones
Use grid paper when available
Follow sketching and text conventions
Do NOT use a straight edge to draw lines!
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Sketching Tips
Sketching straignt
lines does not
mean they have
to look like they
are machine
drawn.
Sketching Tips: Construction
Lines
Use construction lines
Begin by drawing bounding boxes with
construction lines
Make construction lines much lighter
and thinner than finished lines
Identify the major features and overall
dimensions
Leave construction lines on the sketch
11
Drawing Circles
Two methods for
sketching circles
Box in diameter
and mark radius
Draw center-point
lines and mark
radius
Sketching Tips: Miscellaneous
Do not shade the drawing – this is not
pencil sketching
Title information is required
Keep views aligned (very important)
Draw neat circles – change page
orientation if needed
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Sketching techniques
Use very light construction lines
“Box in” the rough outline of the object
Darken only the lines you wish to keep
Clean up the edges and rough spots
Box In Technique
Boxing in the outer dimensions is
often the first step in producing a
sketch
Sketching Tips
If you don’t have a ruler, you can
estimate dimensions using your pencil
when sketching
Always keep your pencil at arms length.
Why?
Sketching Tips
Layout of drawing using your pencil
for dimensional reference
Lettering
The style of engineering lettering we
will use in this course is Single Stroke
Gothic Lettering


An example of the characters is shown on
drawing numbers 1 and 2
Notice that only capital letters are
demonstrated, since we will use only
capital letters on drawings
Lettering Notes
Lettering Guidelines – Handout
Lettering Styles
 Shape of Letters
 Order of Drawing Lines
Character Uniformity
Spacing
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Single Stroke Gothic Lettering
Lettering – Vertical Gothic Font
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Lettering with Fractions
Sketching Techniques