Machine Drawing

Limits, Tolerances, and Fits 211

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d:\N-Design\Des15-1.pm5

Fig. 15.3 Graphical illustration of tolerance zones

Fundamental deviation

Negative

Positive

A

EI

B

C

CD

D

EEF

FFGG H

J

JS

K M N P Zero line

RS T

UV X

Y ZZA

ZB

ES

Basic size

ZC

(a) Holes (Internal features)

Fundamental deviation

Negative

Positive

a

es

b

c

cd

d

e ef

ffggh

j

js

kmnp

Zero line r s t

u v x

y zza

zb

ei

Basic size

zc

(b) Shafts (external features)