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• Placing of dimension – dimension must be placed correctly by using extension

lines or leader.

Figure 4.21 : Geometric breakdown

4.7.1 Chain dimensioning

Chain of single dimensioning should be used only where the possible accumulation of

tolerances does not endanger the fundamental requirement of the component. The

overall dimension (if necessary) is placed outside the other smaller dimensions.

Figure 4.22 : Chain dimensioning

4.7.2 Parallel dimensioning

In this method, a number of dimension lines which are parallel to one another and spaced

out, are used. This method is used where several dimensions have a common datum
feature. Smaller dimensions should always be placed nearer the view. The next smaller

dimension should be placed net and so on.