1. TA 101: Technical Arts 2015-16 II Dr. Prishati Raychowdhury
Department of Civil Engineering
IIT Kanpur
Office: FB 336; Phone: 6692

2. Engineering Drawing Basics
Lecture 2
Engineering Drawing Basics

3. Section-wise Lab Schedule
Day
Sections
Monday
B4, B5, B6
Tuesday
B1, B2, B3
Wednesday
B7, B8, B9
Thursday
B10, B11, B12

4. Section-wise Tutor Details
SL. No.
Section
Day
Tutor
Dept
Tel.
Office Location 1 B1
Tue
Ms. Nidhi Sharma AE 2 B2
Dr. Ashish Dutta ME
7562
FB 338 3 B3
Dr. Ishan Sharma
6152
NL 102 4 B4
Mon
Mr. Yasar Arafath 5 B5
Mr. Rahul Oarath 6 B6
Dr. Amritanshu Sriwastava CE 7 B7
Wed
Dr. Tarun Gupta
7128
FB 310 8 B8
Dr. Ashu Jain
7411
FB 315 9 B9
Dr. B L Sharma
6173
FB 356 10
B10
Thu
Mr. Subhabrata Koley 11
B11
Mr. Sarthak Sambit Singh 12
B12
Dr. Mukesh Sharma
7759
WLE 302

5. Reminder: Things to do before your first lab
Purchase the “Instruction Manual” from Copy Point
Purchase all the instruments
Prepare the free-hand solutions for Laboratory Assignment 1 and bring it to the lab
Bring A3 sheet to do lab#1 on it to the drawing hall.
You are NOT required to submit the Home Assignment 1 next week
Home Assignment 1 is due in the week of Jan 11th to 15th
Lectures are available in

6. How to setup a drafter
Tape the black back sheet to the board

7. Set up the drafter

8. Move the sheet around such that the drafter is able to reach the entire area

9. Identify the final position and tape the sheet securely

10. Drawing Basics

11. Scale
How would you draw a 20 m high building on your drawing sheet? Or a 100 m long bridge?

12. Scale
1:2, 1:5, 1:10 etc
Note: Actual dimension are always written on drawings
Note: A drawing should always mention the SCALE

13. Some basic geometric shapes

14. Some basic geometric shapes
Pyramids
Cylinders & Cones

15. Basic conic surfaces Parabola Circle Ellipse Hyperbola

16. Importance of drawing an ellipse
A circle looks as an ellipse when viewed at an angle
Sharp edges are connected by arcs

17. Ellipse: Basics
Ellipse is a curve generated by a point moving such that the sum of its distance from the focuses (focii) is equal to the major diameter
AB : Major diameter
DE : Minor diameter
F1, F2 : Focii

18. Ellipse: Basics P Q N M A C D B
• Any line through the center of an ellipse may serve as one of
a pair of conjugate diameters.
• Two diameters are said to be
conjugate when each diameter is parallel to the tangents at the ends of the other diameter.
• AB and CD are a pair of conjugate diameters:
AB // MN, PQ
and CD //MP, NQ.
• A given ellipse may have an unlimited number of pairs of conjugate diameters.

19. Conjugate Diameter Method
• From S, P, etc. draw lines parallel to
QD and from S', P', etc. draw lines
parallel to ER. Q S
• Conjugate diameters AB and DE given. P
• Draw a circle with AB as diameter. O
• Draw OQ perpendicular to AB.
• Intersection of lines through P & P', S
& S', etc. give points on the ellipse.
• From a number of points on either side
of Q, such as P and S, draw
perpendiculars PP', SS', etc. to AB. P’ S’ R
An approx method

20. Concentric Circle MethodP θ 2b 2a
An exact method

21. Parallelogram Method D G 3 • Can be used either with the major
and minor diameters or with any
pair of conjugate diameters. 2
• Through these points draw lines
from D and E as shown. 1 O A 1 2 3 B E
• On the given diameters construct
a parallelogram.
• Their intersections will be points
on the ellipse. D G 3 2
• Divide AO into any number of
equal parts and AG into the same
number of equal parts, numbering
points from A. 1
Conjugate diameters O A B 1 2 3 E
An exact method

22. 4-Centered Method A’ P D F A B O Q S E R
An approx method

23. Constructional geometry
Draw a rhombus and inscribe an ellipse inside it (APPROXIMATE): 2
• Mark mid points of all sides
as A,B,C,& D.
• Taking 1 as center and 1-A
radius draw an arc AB.
• Join these points to the
ends of smaller diagonals. 3 4
• Take 2 as center draw an arc CD and so on.
• Mark points 1,2,3,4 as
four centers. 1

24. Construction of A Parabola7 6 5 4 3 2 1 6 7 5 4 3 2 1

25. Polygons: Hexagon Circumscribing circle Inscribing circle d d 60
Vertex-to-vertex distance
Distance between flats

26. Polygons: Octagon

27. Polygons: Septagon or any regular polygon
Given a side 3 4 2 5 6 7 B A

28. Thank you..