Operational Cautions - Hitachi Koki WH 14DDL Mode D'emploi

NOTE:
The appropriate mode differs depending on the screw
and the material being screwed. Drive in a few test
screws and adjust the mode setting accordingly.
Rotation speed
"Delicate work"
Tightening small
Use
diameter screws
(M6 or similar), etc.
7. Tightening and loosening screws
Install the bit that matches the screw, line up the bit in
the grooves of the head of the screw, then tighten it.
Push the impact driver just enough to keep the bit
fitting the head of the screw.
CAUTION
Applying the impact driver for too long tightens the
screw too much and can break it.
Tightening a screw with the impact driver at an angle
to that screw can damage the head of the screw and
the proper force will not be transmitted to the screw.
Tighten with this impact driver lined up straight with
the screw.
8. Tightening and loosening bolts
A hex. socket matching the bolt or nut must first be
selected. Then mount the socket on the anvil, and
grip the nut to be tightened with the hex. socket.
Holding the tool in line with the bolt, press the power
switch to impact the nut for several seconds.
If the nut is only loosely fitted to the bolt, the bolt
may turn with the nut, therefore mistaking proper
tightening. In this case, stop impact on the nut and
hold the bolt head with a wrench before restarting
impact, or manually tighten the bolt and nut to prevent
them slipping.

OPERATIONAL CAUTIONS

1. Resting the unit after continuous work
After use for continuous bolt-tightening work, rest
the unit for 15 minutes or so when replacing the
battery. The temperature of the motor, switch, etc.,
will rise if the work is started again immediately after
battery replacement, eventually resulting in burnout.
NOTE:
Do not touch the metal parts, as it gets very hot
during continuous work.
2. Cautions on use of the speed control switch
This switch has a built-in, electronic circuit which
steplessly varies the rotation speed. Consequently, when
the switch trigger is pulled only slightly (low speed
rotation) and the motor is stopped while continuously
driving in screws, the components of the electronic
circuit parts may overheat and be damaged.
3. Use a tightening time suitable for the screw
The appropriate torque for a screw differs according to
the material and size of the screw, and the material
being screwed etc., so please use a tightening time
Examples of tightening mode selector function settings
Low Medium
-1
900 min 2200 min
"Light load work"
Affixing plasterboard
etc.
The tightening mode selector switch can only be set
after the battery has been installed in the driver and
the trigger switch has been pulled once.
High
3000 min
-1
/3100 min
"Heavy load work"
Tightening long
screws, coach
screws, bolts, etc.
suitable for the screw. In particular, if a long tightening
time is used in the case of screws smaller than M8, there
is a danger of the screw breaking, so please confirm the
tightening time and the tightening torque beforehand.
4. Work at a tightening torque suitable for the bolt
under impact
The optimum tightening torque for nuts or bolts differs
with material and size of the nuts or bolts. An
excessively large tightening torque for a small bolt
may stretch or break the bolt. The tightening torque
increases in proportion to the operaton time. Use the
correct operating time for the bolt.
5. Holding the tool
Hold the tool firmly with both hands. In this case hold
the tool in line with the screw or bolt.
It is not necessary to push the tool very hard. Hold
the tool with a force just sufficient to counteract the
impact force.
6. Confirm the tightening torque
The following factors contribute to a reduction of the
tightening torque. So confirm the actual tightening
torque needed by screwing up some bolts before the
job with a hand torque wrench. Factors affecting the
tightening torque are as follows.
(1) Voltage
When the discharge margin is reached, voltage
decreases and tightening torque is lowered.
(2) Operating time
The tightening torque increases when the operating
time increases. But the tightening torque does not
increase above a certain value even if the tool is
driven for a long time.
(3) Diameter of bolt
The tightening torque differs with the diameter of the
bolt. Generally a larger diameter bolt requires larger
tightening torque.
(4) Tightening conditions
The tightening torque differs according to the torque
ratio; class, and length of bolts even when bolts with
the same size threads are used. The tightening torque
also differs according to the condition of the surface
of workpiece through which the bolts are to be
tightened. When the bolt and nut turn together, torque
is greatly reduced.
(5) Tightening torque varies, depending on the battery's
charge level.
English
S mode
-1 3000 min
-1
/3100 min
Self drilling screw
tightening
-1
-1
13