CSVTU

ENGINEERING GRAPHICS AND DESIGN

UNIT 1

1. Briefly explain Principles of Engineering drawing and their

significance?

To record information on paper (or another surface), instruments and equipment are

required. Even for drawings made freehand, pencils, erasers, and sometimes

coordinate paper or other special items are used. The lines made on drawings are

straight or curved (including circles and arcs). They are made with drawing

instruments, which are the necessary tools for laying down lines on a drawing in an

accurate and efficient manner. To position the lines, a measuring device, a scale, is

needed.

The various instruments will be described in detail later, but the opening of this

chapter will serve as an introduction. To draw straight lines, the T square, with its

straight blade and perpendicular head, or a triangle is used to support the stroke of

the pencil. To draw circles, a compass is needed. In addition to the compass, the

draftsman needs dividers for spacing distances and a small bow compass for

drawing small circles. To draw curved lines other than circles, a French curve is

required. A scale is used for making measurements.

2. What are the different types of Lines used in engineering

graphics?

In EngineeringGraphics, the details of various objects are drawn by different types

of lines. Each line has adefinite meaning and sense toconvey.

1.Visible Outlines, Visible Edges: (Continuous wide lines) the lines drawnto

represent the visible outlines/ visible edges / surface boundary lines of objects

should beoutstanding in appearance.

2. Dimension Lines: (Continuous narrow Lines) Dimension Lines are drawnto

mark dimension.