Maintenance And Inspection - Hitachi CM12Y Handling Instructions Manual

English
The cutting can be performed smoothly if you cut
straight ahead on the scribed line in the initial cut.
(2) Turn on the switch when the diamond wheel is not
touching the material to be cut.
CAUTION
Always check the diamond wheel before starting
work. Never use a diamond wheel which is cracked,
broken or bent.
Do not apply water or coolant to the diamond
wheel.
Start cutting only when diamond wheel reaches its
maximum speed.
If the diamond wheel seizes or there is any abnor-
mal noise, immediately turn the power off.
Never use the diamond wheel to cut zig zag or
curved lines. Never use the side surface of the
diamond wheel. Never use to perform inclination
cutting.
If excessive force is applied to the diamond wheel
to make it align with the premarked line during
cutting, this might not only overload the motor and
cause burn damage but may also overheat the
diamond wheel and shorten the service life.
Secure the workpiece. A workpiece clamped with
clamping devices or in a vice is held more securely
than by hand.
Take care not to allow the power cord to come into
contact with the diamond wheel during operation.
When the work is completed, turn the power off
and disconnect the power plug from the receptacle.

MAINTENANCE AND INSPECTION

1. Inspection the diamond wheel
A worn diamond wheel overloads the motor and
reduces working efficiency. Replace with a new one.
2. Diamond Wheel Clogging:
The rate of wear of the diamond layer cutting edge
will vary depending on the type of material being
cut, the cutting speed, etc. In general, materials
which produce granular cutting particles may scrape
the boding agent and hasten the wear of the dia-
mond layer. On the other hand, materials which
produce powdery cutting particles may cause clog-
ging of the diamond layer which will reduce cutting
efficiency. When clogging occurs, additional force
applied in an attempt to increase cutting speed will
sometime cause sparks to appear around the cir-
cumference of the diamond wheel. In such a case,
stop using the cutter and carefully inspect the cutting
edge by rubbing it with your fingers. If the diamond
layer feels smooth (no roughness or abrasiveness),
it is clogged with dust and must be "dressed".
For thorough dressing, approximately 5 meters of
slightly accelerated cutting at a depth of 10mm in
a relative soft material which produces granular
cutting particles (such as a cement block or brick)
will restore the cutting effectiveness of the diamond
layer and will extend the service life of the diamond
wheel.
The diamond material is susceptible to high tem-
peratures and will begin to deteriorate at approxi-
mately 600°C. Higher temperatures will cause de-
composition of the diamond material. Accordingly,
it is important to perform "dressing" as soon as
clogging or sparking occurs.
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3. Inspecting the mounting screws:
Regularly inspect all mounting screws and ensure
that they are properly tightened. Should any of the
screws be loose, retighten them immediately. Fail-
ure to do so could result in serious hazard.
4. Maintenance of the motor
The motor unit winding is the very "heart" of the
power tool.
Exercise due care to ensure the winding does not
become damaged and/or wet with oil or water.
5. Inspecting the carbon brushes (Fig. 8)
The motor employs carbon brushes which are
consumable parts. Since an excessively worn car-
bon brush can result in motor trouble, replace the
carbon brush with a new one having the same
carbon brush numbers shown in the figure when
it becomes worn to or near the "wear limit". In
addition, always keep carbon brushes clean and
ensure that they slide freely within the brush holders.
6. Replacing a carbon brush:
Disassemble the brush cap with a minus-head
screwdriver. The carbon brush can then be easily
removed.
7. Service parts list
CAUTION:
Repair, modification and inspection of Hitachi Power
Tools must be carried out by a Hitachi Authorized
Service Center.
This Parts List will be helpful if presented with the
tool to the Hitachi Authorized Service Center when
requesting repair or other maintenance.
In the operation and maintenance of power tools,
the safety regulations and standards prescribed in
each country must be observed.
MODIFICATIONS:
Hitachi Power Tools are constantly being improved
and modified to incorporate the latest technological
advancements.
Accordingly, some parts may be changed without
prior notice.
NOTE
Due to HITACHI's continuing program of reserch and
development, the specifications herein are subject to
change without prior notice.
Information concerning airborne noise and vibration
The measured values were determined according to
EN50144.
The typical A-weighted sound pressure level: 93 dB (A)
The typical A-weighted sound power level: 106 dB (A)
Wear ear protection.
The typical weighted root mean square acceleration
2
value: 7,5 m/s
Avoid vibration affects being of long duration and con-
tinuous as severe vibration may cause disorders to
health.