Engineering Graphics 2018-19-I Lecture 5 TA101A Engineering Graphics 2018-19-I By Dr. Mukesh Sharma Professor DEPARTMENT OF CIVIL ENGINEERING INDIAN INSTITUTE OF TECHNOLOGY KANPUR KANPUR-208016, INDIA

Quadrant 1 and Quadrant 3 are Used for Orthographic Projections Above Above Front 2nd 1st Quad 3rd Quad 4th Front Viewing Direction is same irrespective of quadrant where object is kept Quadrant 1 and Quadrant 3 are Used for Orthographic Projections In whatever Quadrant the object is in, viewing directions are same In what quadrant, so far, we have been keeping the object in?

Revisit 3rd Angle Projection Scheme This is Profile Plane Here too Observer – Plane - Object RECAP of Concept Object - Plane - Observer

1st Angle Projection Scheme RS LS Front Top See the positions of Front, top, RS, LS Views Examine how different these are from 3rd angle projection And why? Hinge Plane - Object - Observer

Areas to avoid – Place them so to read conveniently 126 450 100 80 Avoid Areas to avoid – Place them so to read conveniently

CORRECT INCORRECT

Omit unnecessary dimensions.

Dimensioning of arcs Single arrow, inclined, show where true shape (aligned and unidirectional)

Equally spaced holes.

Dimensioning in limited spaces 6 3 22 19 4.8 5 22 ø26 18 21.5 12 300’ 45” Dimensioning in limited spaces

} Today’s Quiz Drawn in Title Block to indicate type of projection. Identify the angle of projection } Drawn in Title Block to indicate type of projection. Third angle First angle Third angle

Dimensioning in limited spaces 6 3 22 19 4.8 5 22 ø26 18 21.5 12 300’ 45” Dimensioning in limited spaces

L M G A B E 64 120 L,M C F H K D G,E G J 75 C C,D D, F H,J K J, K H 48 36 L 25 M 75 G 46 A B E 64 120 L,M C F H K D 22 G,E G 35 22 J 64 75 C C,D D, F H,J K J, K H L,G E F,K M C D,J H