Lecture 25 TA 101 A Engineering Graphics 2018

Lecture 25 TA 101 A Engineering Graphics 2018 -19 -I By Dr. Mukesh Sharma Professor DEPARTMENT OF CIVIL ENGINEERING INDIAN INSTITUTE OF TECHNOLOGY KANPUR-208016, INDIA

(1) Sections: A 10, A 11, A 12 and A 14 Date: 03 -11 -2018 (Saturday) Time: 10: 00 AM - 01: 00 PM Venue (for A 10, A 11, A 12): New Core Lab, CC 01 and CC 03 Venue (for A 14): Auto. Desk Lab, Drawing Hall _____________________ (2) Sections: A 1, A 2 and A 3 Date: 05 -11 -2018 (Monday) Time: 10: 00 AM - 01: 00 PM Venue: New Core Lab, CC 01 and CC 03 _____________________ 3) Sections: A 7, A 8 and A 9 Date: 08 -11 -2018 (Thursday) Time: 10: 00 AM - 01: 00 PM Venue: New Core Lab, CC 01 and CC 03 _____________________ (4) Sections: A 4, A 5, A 6 and A 13 Date: 10 -11 -2018 (Saturday) Time: 2: 00 PM - 05: 00 PM Venue (for A 4, A 5, A 6): New Core Lab, CC 01 and CC 03 Venue (for A 13): Auto. Desk Lab, Drawing Hall _______________________ The TAs/Tutors will grade your work on the spot after completion of Lab. Do not delete your work until it is graded and you have consent from TAs/Tutors to delete it. If you want to save your drawing and keep it, you can do so.

All Objects are made of points, lines and planes To develop the surface you need TL of lines and TS of planes

Develop the surface of the object so that it is constructed Developed surface is cut from sheet, paper, leather Object surface is made of lines, planes and points Idea is to develop these surfaces in True Shape. Most important points are find TL of line and TS of planes Remember we want the magnitude of line and plane – for this we do not care about the orientation or it FV and TV. Normally Auxiliary plane method is not used – as you need information for so many lines and many auxiliary views.

Development of Surfaces - Example

How to open – there is a convention It should be inside layer up Developed surface is shown on flat surface seen directly by the observer

True length of line by revolution YH X Path of Revolution Axis XH XF F H F Y YR TL H ӨR TL Axis O YHR ӨH YF OBSERVATION If axis is perpendicular to the plane, the hypotenuse of triangle like XOY R will always give the TL of the line. Or, if perpendicular and base are known so is the TL. YFR

Development of Truncated Prism 4 Measuring line and bend line 3 Lateral edge 3, 5 2, 6 D C, E C, 3 2 5 6 1 1 E C F E A, 1 C E B D F Stretchout or girth D Lateral surface E, 5 3 4 2 F A B B, F A Right section B, 2 and base A D, 4 4 F, 6 Lay off the perimeter of the base on line AA Lap seam A Seam line

ET FT LT KT DT MT Seam line E 1 NT OT F 1 A 1 L 1 AT D 1 JT HT CT OF K 1 BT C 1 M 1 J 1 O 1 MF JF B 1 JR HF HR Development of Truncated Pyramid NF DF H 1 AF N 1 A 1 We should find TL of truncated edges. Is ON or NA see in TL somewhere? Yes in FV. Mark it on developed surface How to get OH in TL? Rotate OH so that it is parallel to hinge line and project it in FV Repeat process for OJ. OM is is already in TL FV. Transfer these on developed surface

Development of Irregular Pyramid A 1 Cr Dr Or Br OF Ar D 1 O 1 C 1 BFCF AR AFDF A 1

Development of an Oblique Pyramid Cr Dr A 1 Seam line O 1 A 1 Or Bend line Ar Br B 1 Or D 1 Stretchout or girth C 1 Axis CRBR BRCR AR, DR ARDR Soldered lap seam

Development of an Truncated Cylinder * * ** * *