Makita 9521NB, Original Instructions Manual

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Additional safety warnings:
17. When using depressed centre grinding wheels,
be sure to use only fiberglass-reinforced wheels.
18. NEVER USE Stone Cup type wheels with this
grinder. This grinder is not designed for these types
of wheels and the use of such a product may result
in serious personal injury.
19. Be careful not to damage the spindle, the flange
(especially the installing surface) or the lock nut.
Damage to these parts could result in wheel
breakage.
20. Make sure the wheel is not contacting the work-
piece before the switch is turned on.
21. Before using the tool on an actual workpiece, let
it run for a while. Watch for vibration or wobbling
that could indicate poor installation or a poorly
balanced wheel.
22. Use the specified surface of the wheel to per-
form the grinding.
23. Watch out for flying sparks. Hold the tool so that
sparks fly away from you and other persons or
flammable materials.
24. Do not leave the tool running. Operate the tool
only when hand-held.
25. Do not touch the workpiece immediately after
operation; it may be extremely hot and could
burn your skin.
26. Always be sure that the tool is switched off and
unplugged or that the battery cartridge is
removed before carrying out any work on the
tool.
27. Observe the instructions of the manufacturer for
correct mounting and use of wheels. Handle and
store wheels with care.
28. Do not use separate reducing bushings or adap-
tors to adapt large hole abrasive wheels.
29. Use only flanges specified for this tool.
30. For tools intended to be fitted with threaded hole
wheel, ensure that the thread in the wheel is long
enough to accept the spindle length.
31. Check that the workpiece is properly supported.
32. Pay attention that the wheel continues to rotate
after the tool is switched off.
33. If working place is extremely hot and humid, or
badly polluted by conductive dust, use a short-
circuit breaker (30 mA) to assure operator safety.
34. Do not use the tool on any materials containing
asbestos.
35. Do not use water or grinding lubricant.
36. 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.
37. When use cut-off wheel, always work with the
dust collecting wheel guard required by domes-
tic regulation.
38. Cutting discs must not be subjected to any lat-
eral pressure.
SAVE THESE INSTRUCTIONS.
WARNING:
DO NOT let comfort or familiarity with product
(gained from repeated use) replace strict adherence
to safety rules for the subject product. MISUSE or
failure to follow the safety rules stated in this instruc-
tion manual may cause serious personal injury.
OPERATING INSTRUCTIONS
Installing the wheel guard (Fig. 1 & 2)
Important:
Always be sure that the tool is switched off and
unplugged before installing or removing the wheel guard.
Mount the wheel guard with the tab on the wheel guard
band aligned with the notch on the bearing box. Then
rotate the wheel guard counterclockwise. Be sure to
tighten the screw securely.
Side grip (auxiliary handle) (Fig. 3)
For your own safety, always use the side grip. The side
grip can be installed on either side of the tool.
Installing or removing the depressed center
wheel (Fig. 4 & 5)
Important:
Always be sure that the tool is switched off and
unplugged before installing or removing the wheel.
Mount the inner flange onto the spindle. Fit the wheel on
over the inner flange and screw the lock nut onto the
spindle. Press the shaft lock to prevent spindle rotation,
then use the lock nut wrench to tighten the lock nut
securely.
Warning:
Only actuate the shaft lock when the spindle is not mov-
ing.
Switching ON and OFF (Fig. 6)
CAUTION:
Before plugging in the tool, always check to see that the
switch actuates properly and returns to the ‘‘OFF’’ posi-
tion when the rear of the switch lever is depressed.
To switch on, depress the rear of the switch lever and
push it forward. The depress the front of the switch lever
to lock it.
To switch off, depress the rear of the switch lever.
Operation (Fig. 7)
Keep the edge of the wheel or disc at an angle of about
15° – 30° to the workpiece surface. During the break-in
period with a new wheel, do not work the tool in the B
direction. It will cut into the workpiece. Once the edge of
the wheel has been rounded off by use, the wheel may
be worked in both A and B directions.
WARNING:
• It should never be necessary to force the tool. The
weight of the tool applies adequate pressure. Forcing
and excessive pressure could cause dangerous wheel
breakage.
• Continued use of a worn-out wheel may result in wheel
explosion and serious personal injury. Depressed cen-
ter wheel should not be used after it has been worn
down to 90 mm in diameter.
MAINTENANCE
CAUTION:
• Always be sure that the tool is switched off and
unplugged before carrying out any work on the tool.
• Never use gasoline, benzine, thinner, alcohol or the
like. Discoloration, deformation or cracks may result.