Graphics Language

Graphics are visual presentations on some surface such as a wall, paper, canvas, computer screen,
etc, to inform (communicate) or to entertain. Examples of graphics are:

pictures

photographs

visual art

diagrams

engineering drawings, etc
The graphic language is the idea of communicating thoughts from one person to another by
means of graphics. The role of the graphics language is:
i. To communicate ideas
ii. To communicate feelings
iii. To convey information

Written language is essential for discussing concepts, meanings or feelings, the things that do
not have form, whereas things that have form are better explained or captured with the graphic
language. Just as a person must be literate in order to to understand the written language, visual
literacy is also important in order to understand information in graphic form.
Communication by use of graphics has developed along two distinct paths:

Artistic drawing

Technical drawing
Artistic Drawing
Artistic drawings are used to express aesthetic, philosophic or other abstract ideas. They can also
be used to portray decorative aspects, to express joy, sorrow, political or religious beliefs. It can
be carried out on almost any surface and allows many interpretations. Common tools for artistic
drawing are:

graphite pencils

inked brushes

crayons

charcoal

markers

waxed colored pencils, etc.

Introduction to Technical Drawing

Technical drawing (drafting) is the practice of creating accurate descriptions and representations
of existing or imagined physical objects for technical, architectural and engineering needs. They
are used in development of ideas for designs and to convey technical information. Aspects of a
technical drawing include:

shape

size

material

assembly

finish
Essential requirements for a technical drawing include:

Clear and unambiguous

Language independent

accurate

Conform to standards

suitable for duplication

There are three types of technical drawings:

Multi-view drawings (orthographic); one or more views (projections) systematically arranged.

Pictorial; one view drawn in 3D at a specified angle as it would appear in real life.

Schematic (diagrammatic); simplified functional drawing

Drawing conventions (drawing grammar) allow people to communicate more effectively and with
clarity. These conventions are set by various standards organizations such as:

ISO International Organization for Standardization
– ISO 128: Technical Drawings – General principles of presentation.
– ISO 129: Technical Drawings – Dimensioning
– ISO 3098/1: Technical Drawings – Lettering
– ISO 8048: Technical Drawings – Construction Drawings – Representation of views,
sections, cuts.

KEBS Kenya Bureau of Standards
– KS 06-325. Year 1986. Title: Engineering drawing practice. scope: Specifies the
general principles of presentation and practice to be applied to engineering drawings.
Subject: Engineering drawings
– KS 06-1334 Year 1996. Title: Specification for engineer’s squares.

ANSI American National Standards Institute

BS British Standards
These standards ensure quality, safety and interchangeability of products and information. Standards are updated periodically rendering the old ones obsolete.
Technical drawing is referred to as the universal language for Engineering since it can be interpreted
in any part of the world.
1.1.3 Drawing Equipment
List of equipment for technical drawing

Drawing board or drafting table (508 × 610)

T-square

Set of instruments (draughtsman set)

Triangle 45o
-45o
-90o or adjustable sets square.

Triangle 60o
-60o
-90o

Protractor

Pencils HB, H, 2H, 4H

Drawing layout

The Inside border encloses the working area, including the title block and other tables. The border
shall be 20 mm wide on the binding edge and 10 mm wide on the other three sides, with resulting
working area sizes as shown in Tables 1 and 2. The border on the binding edge allows for binding
or hole punching for filing purposes. The drawing layouts can be in two formats:

• portrait, the longer edge is vertical

Title Block
A title block is a system of labeling and cross-referencing drawings so that the may be stored and
when required, identified and located easily and efficiently. Title blocks are used to record all the
important information necessary for the working drawings. It contains general as well as specific
information. The basic requirements for a title block located at the bottom right hand corner
of a drawing are:

• Title of the drawing
• Drafters name and number
• Name of firm or organization
• Scale
• Date
• Dimensions (units of measurements) used
• Drawing number or projection symbol

Lettering
Lettering is used to give dimensions and other pertinent information of what is being drawn.
ANSI recommends that Single Stroke Gothic style be the accepted lettering standard due to
the following reasons:

Written rapidly

Highly legible
Single stroke lettering has all the strokes of uniform thickness, and each stroke is produced by
one movement of the pencil. Figure 1.4 shows sample lettering using Gothic style. Guidelines for

lettering in technical drawing:

Use H or HB pencils when lettering

Pencils should be sharpened to a conical point

Good lettering requires the use of guidelines drawn using construction lines (4H pencil)

Characters should have the simplest form possible

Letter spacing – use uniform area between letters and not uniform spacing

Word and sentence spacing – should be equivalent to the letter height

Letter height

6 mm for upper case letters

4 mm for lower case letters

For dimensions and notes, a character height of 3 mm should be used.

Spacing between lines of letters should be at least 2
3 the letter height

Lettering guides can be used (AMES lettering guide)fraction : 4
5 not 4/5

Line Types

Thin line lines that are dark, and drawn with 2H pencil include: centerlines, extension lines,
dimension lines, leader lines, section lines, hidden lines.
Thick lines that are dark and drawn with a HB pencil include; outlines, visible lines

Very thick lines that are dark and drawn with a B pencil include: cutting plane lines, viewing
plane lines.
Thin Light lines drawn with a 4H pencil include: Guidelines used for lettering, construction lines
Dark features drawn with a HB pencil include: arrowheads, lettering