PRECISION MEASURING AND GAGING - OD1642 - LESSON 1/TASK 2
are made. A certain amount of this wear may be taken up by adjusting the
vernier scale itself. This scale is mounted with screws in elongated holes
which permit it to be adjusted slightly to compensate for wear and
distortion. When the error exceeds 0.0002 of an inch, either in parallelism
or flatness, the caliper should be returned to the manufacturer for
reconditioning. Wear on the jaws can best be checked by visual means and by
using measuring rolls or rings of known dimensions.
FIGURE 47.
USING A VERNIER CALIPER.
(c) When the machinist is finished using the verniers for the day,
he should coat all metal parts with a light coat of oil to prevent them from
rusting. Calipers should be stored in separate containers that are provided
for them. The graduations and markings on all calipers should be kept clean
and legible.
(d) Care should be taken to prevent dropping any caliper, as small
nicks or scratches can cause
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