Engineering Graphics

INDEX• Introduction• Scales• Engineering Curves• Orthographic Projection• Isometric Projection• Projection of Points & Lines• Projection of Planes• Projection of Solids• Section of Solids

IN CLASS

INTRODUCTION•Types of Lines•Numbering•Dimensioning•Types of Polygon

TYPES OF LINESTYPE ILLUSTRATION APPLICATION

CONTINUOUS THICK Visible outlinesCONTINUOUS THIN Dimension lines, Leader

lines, extension linesCONTINUOUS THIN - WAVY Irregular boundary lines

SHORT DASHES Hidden outlines & edgesLONG CHAIN THIN Center lines, locus lines,

pitch circlesLONG CHAIN LINE

THICK AT ENDSTHIN ELSEWHERE

Cutting plane lines

LONG CHAIN THICK To indicate surface to receive additional treatment

RULED LINE & SHORT ZIG-ZAG THIN Long break lines

NUMBERING

STRAIGHT LETTERS & NUMERALS

• Step-1 First draw two horizontal lines of any length at the distance 10 mm apart from each other.

• Step-2 Then draw vertical lines between the two horizontal lines at distance 10 mm apart form each other.

• Step-3 Then write down the Capital Alphabet letters within each box in such a way that each letter of the alphabet should touch the boundary of the respective box only. Like in the same way write down full ABCD….

• Step-4 As per the procedure described above write down numerals from 1 to 0 in a new line.

INCLINED LETTERS & NUMERALS

• Step-1 First draw two horizontal lines of any length at the distance 10 mm apart from each other.

• Step-2 Then draw vertical lines between the two horizontal lines such that each vertical line should be inclined at an angle of 75° with the horizontal line & each line should be at the distance of 10 mm apart from each other.

• Step-3 Then write down the Capital Alphabet letters within each box in such a way that each letter of the alphabet should touch the boundary of the respective box only. Like in the same way write down full ABCD….

• Step-4 As per the procedure described above write down numerals from 1 to 0 in a new line.

DIMENSIONING

There are two types of dimensioning system:– Uni-Directional System– Aligned System

• In Unidirectional Method of Dimensioning the dimension line should be cut at center and dimensions should be placed in the middle of dimension lines as shown into the figure.

• In Aligned Method of Dimensioning the dimension line should be continuous and dimensions should be placed in the middle of dimension lines as shown into the figure

Polygon

30A B

C

4

6

BASIC DRAWING

• TRIANGLE• SQUARE• PENTAGON• HEXAGON• SEPTAGON• OCTAGON

How to draw a Polygon?

30A B

C

4

6

TRIANGLE

30A B

C

4

6

SQUARE

O

RADIUS

30A B

C

4

6

PENTAGON

BISECTOR

RADIUS5

30A B

C

4

6

HEXAGON

RADIUS

30A B

C

4

6

OCTAGON

8

RADIUS