Hitachi electric disc grinder Benutzerhandbuch

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English
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NOTE:
Use caution not to turn the dial scale to any value
below 1 or above 6.
Fig. 4
CAUTION:
When using the grinder in the immediate vicinity
of welding equipment, the rotational speed may
become unstable. Do not use the grinder near
welding equipment.
4.
Use light grinding pressure.
There is no need to press hard when grinding.
Usually the grinder’s own weight is sufficient to
allow the required light contact with the surface to
be ground.
Do not apply the grinding wheel strongly to the
grinding surface. The grinder makes use of
electronic circuit, so during application of load
rotates at high speed, so ample grinding effect can
be obtained by applying light pressure. If a strong
grinding pressure or other abnormal load is
applied, the overload protection circuit will operate
and make the grinder stop rotating, so please stop
applying load immediately. Following this,
switching the power OFF and then ON again, will
cause the rotation to increase to the regular speed.
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).
WARNING:
Do not press the grinder forcibly against the
surface to be ground. Heavy pressure can result
in wheel breakage and serious injury. It can also
damage the surface being ground or damage the
grinder’s motor.
5.
Use proper grinding angle.
Grind only with the wheel’s edge by lifting the
grinder 15° to 30°, as shown in Fig. 5.
CAUTION:
Do not use the entire surface of the depressed
center wheel. Use only the edge of the depressed
center wheel.
6.
Move the grinder in the proper direction.
When using a new depressed center wheel in
direction A (Fig. 5), the wheel edge may cut into the
workpiece. In this case, grind in direction B (Fig. 5).
Once the wheel edge is worn, the workpiece can be
ground in both directions.
Fig. 5
NOTE:
The wheel provided (resinoid wheel) is rated as
Class A grain and # 36 grain size. It is most suitable
for heavy grinding of steel and other types of
materials.
7.
Adjust operation to desired finish.
For a fine finish, decrease pressure by lifting
slightly. Grind slowly and at the appropriate speed.
CAUTION:
The revolving depressed center wheel will create
air turbulence.
Do not lay the grinder down in areas of dust or
dirt until it has come to a complete stop.
DEPRESSED CENTER WHEEL ASSEMBLY
AND DISASSEMBLY
WARNING:
Never attempt to assemble or disassemble the
depressed center wheel,  unless the power switch
is in the “OFF” position and the electrical cord has
been disconnected from the receptacle.
1.
Assembly
(1) Turn the disc grinder upsidedown so that the
spindle is facing upward.
(2) Align the oval-shaped indentation of the wheel
washer with the notched part of the spindle, then
attach them.
(3) Fit the protuberance of the depressed center wheel
onto the wheel washer.
15
° – 30°
A
B
Dial
 01Eng_G12VA_US
8/3/09, 17:51
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