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Figure 2-34.-Drafting machine with enclosed steel bands. | Up
Engineering Aid 3 - Beginning Structural engineering guide book | Next
YOUR EQUIPMENT AND MATERIALS |
CHAPTER 3
DRAFTING: FUNDAMENTALS AND
TECHNIQUES; REPRODUCTION PROCESS
In this chapter you will learn the fundamental and
basic techniques associated with the use of drafting
equipment and accessories commonly used by the EA
in preparing drawings and charts. The techniques are
applied using standard drawing format, line
conventions, and lettering described in detail in two of
the publications you will use most often:
DoD-STD-100C, Engineering Drawing Practices, and
MIL-HDBK-1006/1, Policy and Procedures for Project
Drawing and Specification Preparation. It is your
responsibility to keep up to date on these publications
and other applicable reference materials to ensure that
your drawings are prepared according to the latest
revisions.
This chapter also covers the procedures related to
the safe use and maintenance of the typical reproduction
equipment and discusses the different methods of
reproducing drawings and the types of drawing paper
used.
This training manual will not cover specific
reproduction responsibilities since each command may
have different reproduction equipment depending on its
mission and the size of its engineering department.
When you are assigned this responsibility, you will be
given additional on-the-job training.
WORK PREPARATION
Before you begin to work, you should devote some
time and thought to organizing your working area.
Drafting furniture should be arranged so you can work
comfortable y without fatigue or eyestrain. Be sure to
check the lighting before you set up your drafting table.
You can devise a system of stowing your equipment and
supplies so that they are handy and in order.
WORK AREA
Your immediate work area should be large enough
to allow sufficient freedom of movement, but not so
large that you waste time reaching for equipment,
supplies, and reference publications. An ideal working
area allows each draftsman approximately 90 sq ft of
space, although you may actually have more or less
depending on the total area of the drafting room and the
number of draftsmen who will work there.
If you are easily distracted, do not butt your drafting
table up against and facing another draftsman’s table.
Ensure that you have adequate lighting. The best
light for drafting is natural light coming over the left
shoulder and from the front left to avoid shadows cast
by your hands, T square or parallel ruling straightedge,
and triangles. Avoid a glaring light as it will cause
eyestrain. Use the drafting lamp that was described in
chapter 2. Your drafting table height should be from 36
to 40 in. above floor level. Your drafting chair or stool
should be high enough that you can see the whole
drawing board, but not so high that you have to lean
over uncomfortably to draw. As mentioned in chapter
2, the board may be inclined or left flat according to
your preference. A slope of 1 to 8 works well for the
inclined position.
By shifting your body or head
slightly, you should be able to look directly at any point
on an average-sized drawing sheet; that is, your line of
sight should be approximately perpendicular to the
drawing surface.
Before you begin to draw, arrange your equipment
in an orderly manner. Place each article so that you can
reach it easily, and keep it in place when you are not
using it. A systematic arrangement is timesaving and
efficient. You decrease the likelihood of accidentally
dropping your tools or pushing them off the table if you
keep them in order. You will find it very convenient to
have a small worktable adjacent to your drafting board.
Placing your drafting tools and reference publications
on the worktable leaves you with an uncluttered
drawing board surface.
When you use the drafting
board in the inclined position, a separate worktable
becomes a necessity.
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