Hitachi W 6VB2, Technical And Service Manual, Page: 10 / 25

--- 7 ---
Specific adjustment procedures are as follows
(1) Head of screw protrudes above workpiece surface (Fig. 1)
If dimension A in Fig. 3 is excessively small, the head of the driven screw will protrude above the surface of the
workpiece material as shown in Fig. 1. To adjust dimension A, pull the lock sleeve in the direction indicated by
the arrow in Fig. 3 to disengage the lock sleeve from the gear cover spline, and rotate the lock sleeve
clockwise as viewed from the screw mounting end (see Note below). Repeat adjustment as necessary until
the head of the driven screw is properly aligned with the surface of the workpiece.
(2) Head of screw sinks below workpiece (Fig. 2)
If dimension A in Fig. 3 is excessively large, the head of the driven screw will sink below the surface of the
workpiece as shown in Fig. 2. To perform adjustment, follow the procedures described in item (1) above, but
rotate the lock sleeve counter-clockwise.
Should Hex and Teks screws be driven when dimension A is excessively large, both the screws and bits may
be easily damaged. Instruct customers/users to perform adjustment correctly without fail.
(NOTE) By turning the lock sleeve clockwise or counter-clockwise, dimension A in Fig. 3 can be adjusted
within a maximum dimension of 1.5 mm (0.059"). One complete rotation of the lock sleeve is
divided into ten settings, each setting permitting an adjustment of 0.15 mm (0.006"). Accordingly,
if dimension B in Fig. 1 is 0.3 mm (0.012"), rotate the lock sleeve by two settings.
7-4. Self-Drilling Screws
Self-drilling screws are most suitable for joining wooden and metal materials, mounting metallic components onto
iron sheets, or installing roofing materials. Self-drilling and self-tapping, they are commonly employed in the
construction industry because:
Separate drilling and tapping processes are not required when securing wooden materials to metal materials.
Consequently, job costs and processes can be drastically reduced.
7-5. Drywall Screws
Drywall screws are most suitable for interior decorating and construction utilizing such materials as gypsum board
and plastic board. Their main features are:
Like Hex and Teks screws, drywall screws are self-drilling, and can reduce work time.
Wall panels can be mounted cleanly without cracks or chips.
Drywall screws display far stronger holding power than conventional screws when applied to materials
composed of powder or particles, such as gypsum board.
Fig. 1 Fig. 2 Fig. 3
Screw
Locator
Gear cover
Lock sleeve
Sub-stopper
A
Material into which screw
is driven Material into which screw
is driven
Screw
Screw
B