The document discusses engineering graphics and drawing, including the importance of drawing as a universal language for engineers. It describes various drawing instruments used to prepare accurate drawings, such as the drawing board, T-square, set squares, protractor, compass, and types of pencils. The document also outlines different types of lines used in engineering drawings, such as outlines, hidden lines, center lines, and cutting plane lines.

1. Engineering
Graphics I By
Nitin G Shekap
Introduction To Engineering Graphics
(L1)

2. Which Language do you Speak…!
To Communicate
Why do you use it ?
To express
Ideas
Feelings
By: Nitin Shekapure

3. Drawing
Describing any object/ information diagrammatically
By: Nitin Shekapure

4. Graphical means of expression of technical details
without the barrier of a language.
Engineering Drawing
Universal language for engineers
By: Nitin Shekapure
Drawing is a graphic representation of:
• a real thing,
• an idea or,
• a proposed design for later manufacture or construction.

5. What Engineering Students Should Know?
• For any product design or development, graphical language is always
required with technical knowledge.
• Today the close connection between engineering and science, and the
universal graphic language is more vital that even before.
• Artistic talent is no longer a prerequisite to learning the fundamentals
of the graphic language.
• Instead today’s graphics student needs the same aptitudes, abilities
and computer skills that are needed in science and engineering
courses.
• A well trained engineers must be able to make and read correct
graphics representations of engineering structures, designs and data
relationships.

6. What Engineering Students Should Know?
• Understand the fundamental principles or the grammar of the
language and be able to execute the work with reasonable skill.
• Students will learn the meaning of neatness, speed, and accuracy
for the first time in a drawing course. These are basic and
necessary habits for every successful engineer.
• The ability to think in three dimensions.
• Learning to visualize objects in space, to use the constructive
imagination is one of the principal values to be obtained from a
study of the graphic language.

7. Diagrams/sketches/pictures – communication skills
• We grasp information easily if it is illustrated with
diagrams, sketches, pictures, etc.
LCA - the world's smallest, light weight, multi-role
supersonic combat aircraft of the world
By: Nitin Shekapure

8. AIRBUS A380
Details: largest passenger jet. 80m wingspan and a tail that
stands as high as a seven-storey building, carries more than
550 passengers.
By: Nitin Shekapure

9. It would just be impossible to communicate all
necessary details about the LCA/ Airbus A380
verbally or in writing – Illustration (picture/drawing)
is useful.
• A picture/drawing is worth a thousand words..
• The LCA/Airbus A380 would be impossible to
create without computer graphics and drawing
models.
•Drawings are the road maps which show how to
manufacture products and structures.
By: Nitin Shekapure

10. Impossible to describe the details of the building
By: Nitin Shekapure

11. ???
By: Nitin Shekapure

12. Drawing Instruments
Drawing Instruments are used to prepare neat and accurate Drawings.
To a greater extent, the accuracy of the Drawings depend on the
quality of instruments used to prepare them. The following is the list
of Drawing Instruments and other materials required.
By: Nitin Shekapure

13. Drawing Instruments
1. Drawing Board
Drawing board is made from strips of well seasoned soft
wood generally 25 mm thick.
One of the shorter edges of the rectangular board is
provided with perfectly straight ebony edge which is used
as working edge on which the T-square is moved while
making Drawings.
By: Nitin Shekapure

14. Drawing Instruments
1. Drawing Board
Designation Size (mm) Name
B0 1500 x 1000 Antiquarian
B1 1000 x 700 Double elephant
B2 700 x 500 Imperial
B3 500 x 350 Half Imperial
Sizes of Drawing Boards
By: Nitin Shekapure

15. Drawing Instruments
2. T-square or Drafter (Drafting machine)
T-squares are made from hard wood. A T-square consists of
two parts namely the stock and the blade joined together at
right angles to each other by means of screws and Pins. The
stock is made to slide along the working edge and the Blade
moves on the Drawing board.
By: Nitin Shekapure

16. Drawing Instruments
2. T-square or Drafter (Drafting machine)
In a Drafting machine, the uses and advantages of T-square,
set square, scales, protractors are combined. One end of the
Drafter is clamped at the left top end of the Drawing board
by a screw provided in the drafter.
An adjustable head with a Protractor is fitted at the other
end of the Drafter. Two blades made of transparent celluloid
material are fitted to the adjustable head and are perfectly
perpendicular to each other.
These blades are used to draw parallel, horizontal, vertical
and inclined lines. The blades always move parallel to the
edges of the board. Use of Drafting machine helps in
reducing the time required to prepare Drawing.
By: Nitin Shekapure

17. Drawing Instruments
2. T-square or Drafter (Drafting machine)
By: Nitin Shekapure

18. Drawing Instruments
2. T-square or Drafter (Drafting machine)
By: Nitin Shekapure

19. Drawing Instruments
3. Set Squares
Set squares are generally made from Plastic or celluloid
material. They are triangular in shape with one corner, a right
angle triangle. A pair of set squares (30°–60°) and 45° (45°
set square are generally provided with Protractor) facilitate
marking of angles as shown in figures.
They are used to draw lines at 30°, 60° and 45° to the
vertical and horizontal.
By: Nitin Shekapure

20. Drawing Instruments
4. Protractor
Protractors are used to mark or measure angles between 0
and 180°. They are semicircular in shape (of diameter 100mm)
and are made of Plastic or celluloid which has more life.
Protractors with circular shape capable of marking and
measuring 0 to 360° are also available in the market.
By: Nitin Shekapure

21. Drawing Instrumentsc
5. Drawing Instrument Box
By: Nitin Shekapure

22. 6. Drawing Sheet
Drawing Instruments
They are available in many varieties and good
quality paper with smooth surface should be
selected for Drawings which are to be
preserved for longer time. Sizes of Drawing
Sheets recommended by Bureau of Indian
Standards (B.I.S) is given below,
Designation Size (mm) Designation Size (mm)
A0 1189 × 841 A3 420 × 297
A1 841 × 594 A4 420 × 210
A2 594 × 420 A5 210 × 148
By: Nitin Shekapure

23. 7. Drawing Pins and clips
Drawing Instruments
These are used to fix the Drawing sheet on the Drawing
board.
By: Nitin Shekapure

24. By: Nitin Shekapure
8. Compass
Drawing Instruments
Compass is used for drawing circles and arcs
of circles. The compass has two legs hinged
at one end. One of the legs has a pointed
needle fitted at the lower end where as the
other end has provision for inserting pencil
lead. Circles up to 120mm diameters are
drawn by keeping the legs of compass
straight. For drawing circles more than 150
mm radius, a lengthening bar is used. It is
advisable to keep the needle end about 1mm
long compared to that of pencil end so that
while drawing circles, when the needle end is
pressed it goes inside the drawing sheet by a
small distance (approximately 1mm).

25. 9. French Curves
Drawing Instruments
These are used for drawing smooth curved lines that are not
arcs or circles. These are used to draw irregular curves such
as ellipse, parabola, spiral etc. It comes in verity of shapes
and sizes.
By: Nitin Shekapure

26. 10. Drawing Pencils
Drawing Instruments
The accuracy and appearance of a Drawing depends on the quality of
Pencil used to make Drawing.
The grade of a Pencil lead is marked on the Pencil. HB denotes
medium grade. Increase in hardness is shown by value put in front of
H such as 2H, 3H etc., Softer pencils are marked as 2B, 3B, 4B etc.
A Pencil marked 3B is softer than 2B and Pencil marked 4B is softer
than 3B and so on. Beginning of a Drawing may be made with H or 2H.
For lettering and dimensioning, H and HB Pencils are used.
By: Nitin Shekapure

27. 10. Eraser
Drawing Instruments
Eraser, popularly known as rubber.
Always use good quality soft rubber so that due to its use the
surface of drawing paper dose not get damaged.
By: Nitin Shekapure

28. By: Nitin Shekapure
TYPE ILLUSTRATION APPLICATION
A – Continuous Thick Visible Outlines
B – Continuous Thin
Dimension Lines, Leader Lines,
Extension Lines, Construction Lines
of Adjacent Parts
C – Continuous Thin- Wavy
Irregular Boundary Lines, Short
Break Lines
D – Short Dashes Medium Hidden Outlines & Edges
E – Long Chain Thin
Centre Lines, Locus Lines, Extreme
Positions of The Movable Parts
Situated In Front of The Cutting
Plants And Pitch Circles
F – Long Chain Line Thick
at Ends & Thin Elsewhere
Cutting Plane Lines
G – Long Chain Thick
To Indicate Surfaces Which are to
Receive Additional Treatment
H – Ruled Line & Short
Zigzag Thin.
Long Break Lines
Types of Lines used in Engineering Graphics

29. Types of Lines used in Engineering Graphics
By: Nitin Shekapure
Outlines (A): Lines drawn to represent
visible edges and surface boundaries of
objects are called outlines or principal
lines. They are continuous thick or
wide lines
Extension or projection lines (B):
These lines also are continuous thin lines.
They extend by about 3 mm beyond the
dimension lines
Dimension lines (B): These lines are
continuous thin lines. They are
terminated at the outer ends by
pointed arrowheads touching the
outlines, extension lines or centre lines

30. Types of Lines used in Engineering Graphics
By: Nitin Shekapure
Hatching or section lines (B): These
lines are drawn to make the section
evident. They are continuous thin lines
and are drawn generally at an angle of
45° to the main outline of the section.
They are uniformly spaced about 1 mm
to 2 mm apart
Hidden or dotted lines (E): Interior or
hidden edges and surfaces are shown by
hidden lines. They are also called dotted lines.
They are of medium thickness and made up of
short dashes of approximately equal lengths of about 2 mm spaced at equal
distances of about 1 mm. When a hidden line meets or intersects another
hidden line or an outline, their point of intersection or meeting should be
clearly shown
Leader or pointer lines (B): Leader
line is drawn to connect a note with
the feature to which it applies. It is
a continuous thin line

31. By: Nitin Shekapure
Centre lines (G): Centre lines are drawn to indicate the axes of cylindrical,
conical or spherical objects or details, and also to show the centre’s of circles
and arcs. They are thin, long, chain lines composed of alternately long
and dot spaced approximately 1 apart. The long dashes are about 9 to 12 mm.
Centre lines should extend for a short
distance beyond the outlines to which
they refer. For the purpose of dimensioning
or to correlate the views they may be
extended as required. The point of
intersection between two centre lines
must always be indicated. Locus lines,
extreme positions of movable parts and
pitch circles are also shown by this type of line.

32. By: Nitin Shekapure
Short-break lines (C): These lines are
continuous, thin and wavy. They are
drawn freehand and are used to show a
short break, or irregular boundaries
Long-break lines (D): These lines are
thin ruled lines with short zigzags
within them. They are drawn to show
long breaks
Cutting Plane Line (H): These lines
are thin ruled lines with short zigzags
within them. They are drawn to show
long breaks

33. By: Nitin Shekapure
Home Work
Draw the following Diagrams with the help of Engineering
instruments and with reference to the types of Lines
150
120
150
Fig 1 (A) Fig 1 (B)

34. By: Nitin Shekapure
Home Work
Draw the following Diagrams with the help of Engineering
instruments and with reference to the types of Lines
Fig 1 (C) Fig 1 (D)

35. By: Nitin Shekapure
Home Work
Draw the following Diagrams with the help of Engineering
instruments and with reference to the types of Lines
Fig 1 (E) Fig 1 (F)

36. Home Work
Draw the following Diagrams with the help of Engineering
instruments and with reference to the types of Lines
Fig 1 (G)

37. Home Work
Draw the following Diagrams with the help of Engineering
instruments and with reference to the types of Lines
Fig 1 (H)

38. Home Work
Fig 1 (I)