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,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,LESSON 6,DIMENSIONInG,Learning Objectives:,Explain the basic types of dimensionsing.,Set up dimension style.,Compose dimensions on drawing in accordance with ISO Standard recommendations.,Communicate the feature sizes of engineering component through the dimensions specified in its engineering drawing.,Why Dimension?,Define engineering component by,Size and Shape of features.,Relative locations of features.,Un-ambiguous interpretation of engineering component.,Maintain interchangeability of engineering component.,Part of a Dimension,Arrowhead,Dimension Text,Dimension Line,Projection Line,Leader Line,Extension Line,Basic Concepts of Dimensioning,Dimension:,numerical value defining size, shape, location of design feature.,parallel to dimension line.,preferably near the middle and above the dimension line.,read from the bottom or,read from the right hand side of drawing.,Basic Concepts of Dimensioning,Reference Dimension:,in parentheses.,for information only.,Basic Concepts of Dimensioning,Dimension line:,thin continuous line.,shows the extent and direction of its dimension.,longer ones are placed further that the shorter ones to avoid crossing by projection lines.,Basic Concepts of Dimensioning,Projection line:,thin continuous line.,perpendicular to dimension line.,indicates the feature associated to the dimension.,Basic Concepts of Dimensioning,Arrowhead:,placed at the ends of dimension lines, leader line.,shows the limits of the dimension, leader.,Basic Concepts of Dimensioning,Leader line:,thin continuous line.,indicates the feature associated to that dimension, note.,Basic Concepts of Dimensioning,Small gap:,between the features corner and end of projection line.,Short extension:,beyond the dimension line.,Diameter Symbol ():,precedes a numerical value to indicate diameter of a circle.,Radius Symbol (R):,precedes a numerical value to indicate radius of an arc.,Types of Dimensioning in AutoCAD,Diameter,Radius,Angular,Aligned,Linear,Dimensioning Guidelines,Each feature of an object is dimensioned only once.,Dimensions should be placed in the most descriptive view of the feature being dimensioned.,Dimensions should be located outside the profiles of the object whenever possible.,Crossed dimension lines should be avoided whenever possible.,A small gap should be maintained between the object and the origin of the projection line.,Dimensioning Guidelines,Leader lines used to dimension circles or arcs are to be radial.,Dimension is placed so that it may be read from the bottom or from the right hand side of the drawing.,Concentric cylinders should preferably be dimensioned in its longitudinal view.,Diameters, radii, squares should be specified with appropriate symbol preceding the numerical value.,Dimensioning of hidden features should be avoided.,Dimensioning Rectangular Prism,Dimensioning Cylinder,Diameter and length of cylinder be placed in the longitudinal view.,Size of cylinder must be specified in diameter.,Dimensions preceded by,.,Dimensioning Holes,or,Through Hole,or,Blind drilled Hole,Dimensioning Holes,or,Counterbore Hole,or,Countersunk Hole,Dimensioning Arcs, Fillets and Rounds,Dimensioning Arcs,Dimensioning Fillets and Rounds,Dimensioning Chamfers,Dimensioning 45, chamfers,Dimensioning other,chamfer,Dimensioning Threaded Features,Dimensioning threaded holes,Dimensioning threaded shaft,or,or,Dimensioning,For the figures given below, reproduce a fully dimensioned drawing:,Figure 6.1a,Dimensioning,Dimensioning,Reproduce a fully dimensioned drawing with dimensions.,
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