Yanmar 1GM User Manual page 17

10
/
\
CHAPT ER ON E
/
Correct way to gri nd blade
/
\
\
I \
gree of tape r detennines the point size; the No. 1 Phill ips
screwdri ver will be the mo st pointed. The points becom e
more blun t
as
thei r number increases.
NOTE
There is another screwdriver similar to the
Phillips, and that is the Reed and Prince tip.
Like the Phillips. the Reed and Prince
screwdriver tip f orms an "X ", but the Reed
and Prince tip has a much more pointed tip.
The Reed and Prince screwdriver should
never be used on Phillips screws and vise
versa. Intermixing these screwdrivers will
cause damage
to
the
.~crew
and scre wdriver:
The screw driver is a very basic tool . but ifused im prop-
erly it wi ll do more damage than good. The slot on a scre w
has a defin ite dimension and shape. Through improper
use or selection, a screwdriver can damage the screw
head. making removal of the screw difficult. A screw-
driver must be selected to conform to the shape of the
screw head used . Two basic types of screwdrivers are re-
quired: standard (flat- or slot-blade) screwdrivers (Figure
17) and Phillips screwdrivers (F tgure 18).
Note the following when selecting and using screwdriv-
ers:
I. The screwdriver mu st al ways
fit
the screw head .
If
the
screwdriver blade is too sma ll for the screw slot, damage
may occur to the screw slot
and screwdriv er. If
the blade is
too large,
it
cannot engage the slot prope rly and will res ult
in dam age to the screw head.
2. Standard screwdrivers are identi fied by the len gth of
their blade . A 6-inch screwdriver has a blade six inch es
long. The width of the sc rewdriver blade wi ll vary, so
mak e sure that the blade engages the screw slot com -
ple tely.
3. Phillips screwdrivers ar c size d accord ing to thei r po int
size. They are numb er ed one, two. three and four. The de-
Correct taper and size Taper too steep