Hitachi G12VA Grinder User Manual


 
6
CAUTION
When using the tool at any value except the full
speed (Dial scale 6), the motor cannot be sufficiently
cooled due to the decreased number of revolution.
This could result in the risk of burning and damaging
the motor before an overload protective mechanism
starts to function.
Make sure that you use the tool by lightly applying
it to the surface of material when you use it at any
value except the full speed (Dial scale 6).
2. Grinding angle
Do not apply the entire surface of the depressed
center wheel to the material to be ground. As
shown in Fig. 3, the machine should be held at an
angle of 15° – 30° so that the external edge of the
depressed center wheel contacts the material at an
optimum angle.
3. To prevent a new depressed center wheel from
digging into the workpiece, initial grinding should
be performed by drawing the grinder across the
workpiece toward the operator (Fig. 3 direction B).
Once the leading edge of the depressed center
wheel is properly abraded, grinding may be
conducted in either direction.
4. Precautions immediately after finishing operation
The wheel continues to rotate after the tool is
switched off.
After switching off the machine, do not put it down
until the depressed center wheel has come to a
complete stop. Apart from avoiding serious
accidents, this precaution will reduce the amount
of dust and swarf sucked into the machine.
CAUTIONS
Check that the work piece is properly supported.
Ensure that ventilation openings are kept clear when
working in dusty conditions.
If it should become necessary to clear dust, first
disconnect the tool from the mains supply (use non-
metallic objects) and avoid damaging internal parts.
Ensure that sparks resulting from use do not create
a hazard e.g. do not hit persons, or ignite flammable
substances.
Always use eye and ear protection.
Other personal protective equipment such as dust
mask, gloves, helmet and apron should be worn
when necessary.
If in doubt, wear the protective equipment.
When the machine is not use, the power source
should be disconnected.
ASSEMBLING AND DISASSEMBLING
ACCESSORIES (Fig. 4)
CAUTION: Be sure to switch OFF and disconnect the
attachment plug from the receptacle to avoid
a serious accident.
<DEPRESSED CENTER WHEEL>
1. Assembling (Fig. 4)
(1) Turn the equipment upside-down so that the spindle
will be facing up.
(2) Mount the wheel washer onto the spindle.
(3) Fit the protuberance of the depressed center wheel
onto the wheel washer.
(4) Screw from above the wheel nut onto the spindle.
(5) As shown in Fig. 4, push in the push button to
prevent rotation of the spindle. Then, secure the
depressed center wheel by tightening the wheel nut
with the wrench.
2. Disassembling
Follow the above procedures in reverse.
<RADIAL GRINDING DISC/DIAMOND WHEEL>
Same as depressed center wheel.
<SANDING DISC>
1. Assembling (Fig. 4)
(1) Turn the equipment upside-down so that the spindle
will be facing up.
(2) After placing the sanding disc on the rubber pad,
thread the washer nut onto the spindle.
(3) Press the push button to secure the spindle and
tighten the washer nut with a wrench.
2. Disassembling
Follow the above procedures in reverse.
CAUTIONS
Confirm that the depressed center wheel is mounted
firmly.
Confirm that the push button is disengaged by
pushing push button two or three times before
switching the power tool on.
Fig. 3
AB
15°~30°
01Eng_G12VA_Eng 4/15/09, 17:086