This document contains information about different types of technical drawings and projections used in mechanical engineering. It discusses first and third angle projections, projections of points, lines, planes and solids. It also covers sections of solids, developments of surfaces, and perspective projection. The purpose is to explain key concepts for visualizing and representing 3D objects in 2D technical drawings.

1. DEVAN P D
ASSITANT PROFESSOR
DEPT OF MECHANICAL ENGG
KUMARAGURU COLLEGE OF TECHNLOGY

6. TITTLE BLOCK

7. DIMENSION
S OF
DRAWING
SHEET

24. PROJECTIONS

26. PROJECTIONS OF A POINT IN FIRST QUADRANT

27. FIRST ANGLE PROJECTION

28. THIRD ANGLE PROJECTION

29. First angle Vs Third angle

31. PROJECTIONS OF STRAIGHT LINES

36. PROJECTION OF PLANES

37. PROJECTION of SOLIDS

38. PENTAGONandHEXAGON

39. SECTION of SOLIDS

40. • Hidden features of an object are shown
using dotted lines in their projected views.
• When there are too many hidden features,
it becomes difficult to visualize the object.
• In such cases one usually shows a
sectioned view of the solid – the view
obtained by virtually cutting the solid by a
plane called the section (cutting) plane

42. DEVELOPMENT OF SURFACES

43. • A layout of the complete surface of an object is called a development or pattern.
• The layout of only the sides without the top or bottom is called the lateral surface.
• The development of a solid is the shape of a plain sheet that by proper folding could be converted
into the shape of the concerned solid.

48. PERSPECTIVE
PROJECTION

50. Free Hand
Sketching