IT IS ABOUT BASIC OF ENGINEERING GRAPHICS

1. Branch: : InFOrMaTIOn
TEchnOLOGY
TOPIc : :InTrOducTIOn OF EG
Presented by: Acharya Mansi
Akshay Dhanani
Aandhi Aasif
Ankoliya Riten
Guided by: Jay Shah

2.  draWInG InSTruMEnTS
 ShEET LaYOuT
 ScaLES
 LInES

3.  Engineering drawing is a technique of creating graphical
representation that contains all necessary information
such as dimensions, specifications and notes, using which
an abstract concept can be transformed into real world
object. Application of engineering drawing are valid for
e.g.: Shipping industry, manufacturing, construction and
many more.
 Some important concept of engineering drawing is like
projection. The word projection means to throw forward. It
is a process of plotting an object in an imaginary plane.
Projection has two types:
1. Parallel projection
2. Perspective projection
Each of these has further subtypes.

4. 1. Drawing paper: The size of drawing paper should be less
than drawing board and paper should be fixed properly.
2. Drawing board: It is a plane and smooth surface use for
drawing purpose.
3. T-square: It is a T shape drawing tool whose edge slide
along width of drawing board with the help of stop. It is
useful in drawing straight line.
4. Compass: It is used for drawing circles and arcs. The
divider is little different with both legs made of steel and
use for transferring distance.

5. 5. French Curves: They are used to draw irregular curves
such as ellipse, hyperbola and parabola.
6. Drafter: It is useful tool for drawing parallel lines at any
inclination. It has scale as well as protractor inbuilt.
7. Protractor: It is use to measure and layout angles.
8. Set Square: It is also known as triangle. They comes in
flavors of 30, 60, 30 and 45, 90, 45.

6. Typical Drawing Equipment
Objectives in Drawing
1. Accuracy
2. Speed
3. Legibility
4. Neatness

7.  It is useful tool for drawing parallel lines at any
inclination. It has scale as well as protractor
inbuilt.

8.  They are used to draw irregular curves such as
ellipse, parabola and hyperbola.

9. Drawing Boards
The left edge and right edge of a
drawing board has a true straight
edge.
For right-handed people, the left-
hand edge of the board is called the
working edge because the T-square
head slides against it.
For left-handed people, the right-
hand edge of the board is called the
working edge because the T-square
head slides against it.
T-Squares
The T-square is made of a long strip
called the blade, fastened at right
angles to a shorter piece called the
head.

10. The drawing paper should be placed
close to the working edge of the
board to reduce any error resulting
from the bending of the blade of the
T-square.
The paper should also be placed
close enough to the upper edge of
the board to permit space at the
bottom of the sheet for using the
T-square.
Drafting tape is used to fasten the
drawing paper to the drawing board.

11. Drawing Pencils
High-quality drawing pencils should be used in technical drawing, never ordinary writing pencils.
Many makes of mechanical pencils are available together with refill leads in all grades. Choose
a mechanical pencil that feels comfortable in your hand.

12. HARD MEDIUM SOFT
9H 8H 7H 6H 5H 4H 3H 2H H F HB B 2B 3B 4B 5B 6B 7B
Hard leads are used where extreme
accuracy is required. Generally
these leads are used for
construction lines.
Medium leads are used for general
purpose line work in technical
drawing.
Soft leads are used for various
kinds of art work. These leads are
too soft to be useful in mechanical
drafting.
Drawing Leads
The first consideration in the selection of a grade of lead is the type of line work required. For
light construction lines and guide lines for lettering use a hard lead. For all other line work, the
lines should be BLACK. The lead chosen should be soft enough to produce jet black lines but
hard enough not to smudge.

13. Triangles
Most inclined lines are drawn at standard
angles using the 45º x 45º triangle and
the 30º x 60º triangle.
In addition to drawing angles of 90º, 45º,
30º, and 60º, triangles can be combined
to draw angles of 15º increments.

14. Scales
Scales are instruments used in making
technical drawings full size or at a given
reduction or enlargement.
Types of scales include metric scales,
engineers’ scales, decimal scales,
mechanical engineers’ scales, and
architects’ scales.
Scales are usually made of plastic or
boxwood and are either triangular of flat in
shape.

15.  Margin: Margin is provided in the drawing sheet by
drawing margin lines. Prints are trimmed along this lines.
 Border lines: Clear working space is obtained by drawing
border lines. More space is kept on the left-hand side for
the purpose of filling or binding if necessary.
 Borders and frames: SP:46(2003) recommends the
borders of 20mm width for the sheet sizes A0 and A1, and
10mm for sizes A2, A3, A4 and A5.

16.  Title Block: Space for title
block must be provided in
the bottom right-hand
corner of the drawing sheet.
The size of the title block as
recommended by the B.I.S
is 185mm*65mm for all
designations of the drawing
sheet. All title blocks
should contain at least the
particulars as shown in the
figure:

17. Main Line Types
Lines
Hidden Lines
Center Lines
Dimension Lines
Extension Lines
Leader LinesCutting Planes
Section Lines
Phantom Lines
Viewing Planes
Break Lines
Visible Lines

19. Dimension Lines
• Thin lines capped on the ends with arrowheads and
broken along their length to provide a space for the
dimension numeral.
• They indicate length.

20. Center Lines
• Thin line consisting of alternating long and short
dashes.
• Used to represent the center of round or cylindrical
features, or the symmetry of a feature.

21. seCtion Lines
• Thin line usually drawn at a 45 degree angle.
• Indicates the material that has been cut through in a
sectional view.
Section
Line

22. HiDDen Lines
• Light, narrow, short, dashed lines.
• Shows the outline of a feature that can not be seen in
a particular view.
• Used to help clarify a feature, but can be omitted if
they clutter a drawing.