fixed measuring jaws to measure inside and outside
Do not apply a torque wrench to a nut that has
measurements as shown in figure 5-2. Depth is meas-
been tightened. Back off the nut one turn with
a nontorque wrench and retighten to the cor-
ured using a depth gauge rod.
rect torque with the indicating torque wrench.
Reading the vernier dial caliper is a relatively sim-
ple and easy task involving the addition of the dial
reading to the main frame scale reading. It uses a dial
for all torque tools used in the Navy.
marked in thousandths of an inch and a main frame scale
marked in inches and hundred-thousandths of an inch.
As the dial is drawn across the main frame by an
activity at a shipyard, tender, or repair ship, a label
adjustment screw, the reading is registered on the dial
showing the next calibration due date is attached to the
face in thousandths of an inch. Before taking your
handle. This date should be checked before a torque
measurement, always zero the dial caliper by aligning
tool is used to ensure that it is not overdue for
the mark on the bezel when the measuring jaws are
calibration.
closed. When you pass the first small numbered mark
CALIPERS
on the main frame scale, simply add one hundred thou-
sandths to the dial reading. When you pass the first large
Calipers are precision measuring devices that
numbered mark on the main frame scale, add one inch
measure length in thousandths of an inch. Calipers
to your dial reading. After passing the first small num-
differ only in the way they are read and the types of
bered mark, add one inch one hundred thousandths to
measurements taken. The types of calipers that will be
the dial reading. Do this wherever the reading falls on
discussed in this chapter are the vernier dial caliper
the scale.
and the vernier.
Vernier Caliper
Vernier Dial Calipers
Vernier calipers are capable of taking measure-
Vernier dial calipers are the most common type of
caliper found in use today. They are preferred over
ments to the nearest thousandths of an inch using a sta-
vernier calipers in that they are easier to read and can
tionary and sliding jaw assembly as shown in figure 5-2.
measure depth. They use a double set of movable and
Reading the vernier caliper is not as easy as reading the
Figure 5-2.--Vernier and vernier dial caliper.
5-3