PRINCIPLES AND METHODS
TEXT ASSIGNMENT............................................................................... Attached Memorandum.
Upon completion of this lesson n Principles and Methods, you should be able to accomplish the following in the
indicated topic areas:
Line Conventions. Interpret the established line conventions and symbols used on engineering drawings.
Orthographic Drawings. Describe the fundamentals of orthographic drawings, and how they are used to
Special Views. List and describe the various special views used to supplement an orthographic drawing,
including sections and auxiliaries.
Reproduction of Construction Prints. List and explain the different methods used to reproduce construction
Construction Print Format. Describe the format of a construction print.
Fundamentals of Interpretation. Interpret simple orthographic drawings by relating them to the isometric
views of the objects.
Section I Meaning of Lines
holes. A working drawing of the object is also shown
in figure 1-1.
a. A picture is worth a thousand words. Man
has used pictures as a means of communication for
b. Drawing or sketching is the universal
many years. It would be almost impossible for an
language used by engineers, technicians, and skilled
engineer or an inventor to describe the size and shape
craftsmen. Whether this drawing is made freehand or
of a simple object without a drawing of some kind.
by the use of drawing instruments (mechanical
For example, if an engineer designed a simple object
drawing), it is needed to convey all the necessary
such as that shown in the engineer's sketch in figure
information to the individual who will fabricate and
1-1 it would be difficult to convey his idea to the
assemble the object whether it be a building, ship,
person who is to fabricate the object without a
aircraft, or mechanical device.
drawing to show the shape, size, and location of the