Standard Accessories; Prior To Operation; Practical Grinder Application - Hitachi Koki G 18MRU Handling Instructions Manual

STANDARD ACCESSORIES

(1) Wrench ........................................................................ 1
(2) Side handle ................................................................ 1
Depressed center wheels are not provided as standard
accessories.
Standard accessories are subject to change without
notice.
APPLICATIONS
Removal of casting fin and finishing of various types
of steel, bronze and aluminum materials and castings.
Grinding of welded sections or sections cut by
means of a cutting torch.
Grinding of synthetic resins, slate, brick, marble, etc.
Cutting of synthetic concrete, stone, brick, marble
and similar materials.

PRIOR TO OPERATION

1. Power source
Ensure that the power source to be utilized conforms
to the power requirements specified on the product
nameplate.
2. Power switch
Ensure that the power switch is in the OFF position.
If the plug is connected to a receptacle while the
power switch is in the ON position, the power tool
will start operating immediately, which could cause
a serious accident.
3. Extension cord
When the work area is removed from the power
source, use an extension cord of sufficient thickness
and rated capacity. The extension cord should be
kept as short as practicable.
4. Fitting and adjusting the wheel guard
The wheel guard is a protective device to prevent
injury should the depressed center wheel shatter
during operation. Ensure that the guard is properly
fitted and fastened before commencing grinding
operation.
[Installing and adjusting the wheel guard]
Open the lever and insert the locating pin of wheel
guard, bringing it into line with the across flats of
packing ground.
Then, turn the wheel guard to a desired position
(for use).
Close the lever and fix it. If and when required,
carry out adjustments by tightening or loosening
the screw.
If the lever does not move smoothly, apply some
lubricating oil to the sliding section between the set
piece and the lever.
Fasten the wheel guard at the position where the
across flats of the wheel guard positioning pin and
packing ground are aligned (the position where the
wheel guard is inserted), but do not use it.
5. Ensure that the depressed center wheel to be utilized
is the correct type and free of cracks or surface
defects. Also ensure that the depressed center wheel
is properly mounted and the wheel nut is securely
tightened, refer to the section on "Depressed Center
Wheel Assembly".
6. Conducting a trial run
Ensure that the abrasive products is correctly
mounted and tightened before use and run the tool
at no-load for 30 seconds in a safe position, stop
immediately if there is considerable vibration or if
other defects are detected.
If this condition occurs, check the machine to
determine the cause.
7. Confirm the spindle lock mechanism
Confirm that the spindle lock is disengaged by
pushing push button two or three times before
switching the power tool on (See Fig. 1).
8. Fixing the side handle
Screw the side handle into the gear cover.

PRACTICAL GRINDER APPLICATION

1. Pressure
To prolong the life of the machine and ensure a
first class finish, it is important that the machine
should not be overloaded by applying too much
pressure. In most applications, the weight of the
machine alone is sufficient for effective grinding.
Too much pressure will result in reduced rotational
speed, inferior surface finish, and overloading which
could reduce the life of the machine.
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. Switch operation
Switch ON: Push the locking button forward and
then press the switch lever.
* For continuous use, press the switch
lever. The switch lever is locked by
pushing the locking button forward
once again.
(*Subject to change depending on
area.)
Switch OFF: Press and release the switch lever.
5. Precautions immediately after finishing operation
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.
English
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