The Phillips screwdriver has about 30-degree
flukes and a blunt end, while the Reed and Prince has
45-degree flukes and a sharper, pointed end. The
Phillips screw has beveled walls between the slots; the
Reed and Prince, straight, pointed walls. In addition,
the Phillips screw slot is not as deep as the Reed and
Additional ways to identify the right screwdriver
are as follows:
If the screwdriver tends to stand up unassisted
when the point is put in the head of a vertical
screw, it is probably the proper one.
The outline of the end of a Reed and Prince
screwdriver is approximately a right angle, as
seen in figure 1-74.
In general, Reed and Prince screws are used for
airframe structural applications, while Phillips
screws are found most often in component
Torq-Set machine screws (offset cross-slot drive)
have recently begun to appear in new equipment. The
main advantage of the newer type is that more torque
can be applied to its head while tightening or loosening
than to any other screw of comparable size and material
without damaging the head of the screw.
Torq-Set machine screws are similar in appearance
to the more familiar Phillips machine screws.
Since a Phillips driver could easily damage a
impossible to remove the screw even if the proper tool
is later used, maintenance personnel should be alert to
the differences (fig. 1-73) and make sure the proper tool
An offset screwdriver (fig. 1-71) may be used
where there is not sufficient vertical space for a
standard or recessed screwdriver. Offset screwdrivers
are constructed with one blade forged in line and
another blade forged at right angles to the shank handle.
Both blades are bent 90 degrees to the shank handle. By
alternating ends, most screws can be seated or loosened
even when the swinging space is very restricted. Offset
For fast, easy work, the ratchet screwdriver (fig.
1-71), is extremely convenient, as it can be used
one-handed and does not require the bit to be lifted out
of the slot after each turn. It may be fitted with either a
standard-type bit or a special bit for recessed heads.
The ratchet screwdriver is most commonly used by the
woodworker for driving screws in soft wood.
Screwdrivers, like any other hand tool, are
dangerous when not used properly. Therefore, the
Never use a screwdriver to check an electrical
Never try to turn a screwdriver with a pair of
Do not hold work in your hand while using a
screwdriverif the point slips, it can cause a bad
cut. Hold the work in a vise, with a clamp, or on
a solid surface. If that is impossible, you will
always be safe if you follow this rule: NEVER
GET ANY PART OF YOUR BODY IN FRONT
OF THE SCREWDRIVER BLADE TIP. That is
a good safety rule for any sharp or pointed tool.
Identify the different types of screwdrivers.
List the safety precautions that apply to
LEARNING OBJECTIVES: Describe the
use of mechanical fingers.
Small articles that have fallen into places where
they cannot be reached by hand may be retrieved with
mechanical fingers. Mechanical fingers, shown in
figure 1-75, have a tube containing flat springs, which
extend from the end of the tube to form clawlike
fingers, much like the screw holder. The springs are
attached to a rod that extends from the outer end of the
tube. A plate is attached to the end of the tube, and a
similar plate to be pressed by the thumb is attached to
the end of the rod. A coil spring placed around the rod