TM 9-243
TYPES AND USES
ADJUSTABLE PARALLEL
Adjustable parallels consist of two tapered parts fitted
together. The distance between the two outside parallel
surfaces varies by moving mating parts together or
apart. This distance is then measured with a microme-
ter. Adjustable parallels are used as gages for leveling
and setup work. Adjustable parallels are available in
various sizes depending on the nature of work.
V-BLOCK AND CLAMP
The V-block and clamp assembly consists of a
V-shaped, hardened steel body to support round,
square, or rectangular shaped work. A clamp (or
clamps) holds the work firmly in the body groove.
V-blocks and clamps are especially used for grinding,
milling, or drilling purposes. Various styles and designs
of V-blocks and clamps are available depending on
application.
ANGLE PLATES
Angle plates are devices consisting of two flat outside
working surfaces jointed at right angles. The outside
work surfaces are precision ground. The standard angle
plate is permanently jointed at a right angle. However,
an adjustable type with varying angle adjustments is
also available. Angle plates are used for clamping or
holding work vertically. They are also used for layout,
inspection, or machine set-up. Various sizes and
designs are available depending on the task.
MAGNETIC BASE INDICATOR HOLDER
The magnetic base indicator holder is a one-piece metal
assembly that attaches to the work surface magneti-
cally. A gage or indicator attaches to the assembly.
Base indicator holders are used for attaching gages to
lathes, milling machines, shapers, or any machine
where graduations are difficult to read. Magnetic base
indicator holders are available in many sizes and
designs depending on application.
REGISTERING SPEED INDICATORS
Registering speed indicators are designed to count the
number of revolutions of wheels, shafts, etc. Revolu-
tions are counted by attaching spindle of speed indicator
to hub of shaft or wheel. Indicator spindle will turn in
either direction counting each revolution on a circular
dial. Various designs of speed indicators are available
depending on nature of use.
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