Dongcheng DSJ03-25 User manual

Edition 4 Aug., 2014
Read through carefully and understand these instructions
before use.

GENERAL POWER TOOL SAFETY WARNINGS
(For All Power Tools)
WARNING! Read and understand all instructions. Failure
to follow all instructions listed below may result in electric shock, fire
and/or serious personal injury.
Save all warnings and instructions for future reference.
The term “power tool”in the warnings refers to your mains-operated (corded)
power tool or battery-operated (cordless) power tool.
Work Area Safety
1. Keep work area clean and well lit. Cluttered or dark areas invite accidents.
2. Do not operate power tools in explosive atmospheres, such as in the
presence of flammable liquids, gases, or dust. Power tools create sparks
which may ignite the dust or fumes.
3. Keep children and bystanders away while operating a power tool.
Distractions can cause you to lose control.
Electrical Safety
4. Power tool plugs must match the outlet. Never modify the plug in anyway.
Do not use any adapter plugs with earthed (grounded) power tools.
Unmodified plugs and matching outlets will reduce risk of electric shock.
5. Avoid body contact with earthed or grounded surfaces, such as pipes,
radiators, ranges and refrigerators. There is an increased risk o electric
shock if your body is earthed or grounded.
6. Do not expose power tools to rain or wet conditions. Water entering a
power tool will increase the risk of electric shock.
7. Do not abuse the cord. Never use the cord for carrying, pulling or
unplugging the power tool. Keep cord away from heat, oil, sharp edges or
moving parts. Damaged or entangled cords increase the risk of electric shock.
8. When operating a power tool outdoors, use an extension cord suitable for
outdooruse. Useof acordsuitableforoutdoor use reducestheriskof electricshock.
9. If operating a power in a damp location is unavoidable, use a residual current
device (RCD) protected supply. Use of an RCD reduces the risk of electric shock.
NOTE: The term “residual current device (RCD)” may be replaced by the term
“ground fault circuit interrupter (GFCI)” or “earth leakage circuit breaker (ELCB)”.
Personal Safety
10.Stay alert, watch what you are doing and use common sense when operating a
power tool. Do not use a power tool while you are tired or under the influence
of drugs, alcohol, or medication. A moment of inattention while operating power
tools may result in serious personal injury.
11.Use personal protective equipment. Always wear eye protection. Protective
equipment such as dust mask, non-skid safety shoes, hard hat, or hearing
protection used for appropriate conditions will reduce personal injuries.
12.Prevent unintentional starting. Ensure the switch is in the off-position before
connecting to power source and /or battery pack, picking up or carrying the
tool. Carrying power tools with your finger on the switch or energising power tools
that have the switch on invites accidents.
13.Remove any adjusting key or wrench before turning the tool on. A wrench or a
key left attached to a rotating part of the power tool may result in personal injury.
14.Do not overreach. Keep proper footing and balance at all times. This enables
better control of the power tool in unexpected situations.
15.Dress properly. Do not wear loose clothing or jewellery. Keep your hair,
clothing, and gloves away from moving parts. Loose clothes, jewellery or long
hair can be caught in moving parts.
16.If devices are provided for the connection of dust extraction and collection
facilities, ensure these are connected and properly used. Use of dust collection
can reduce dust-related hazards.
Power Tool Use and Care
17.Do not force the power tool. Use the correct power tool for your application.
The correct power tool will do the job better and safer at the rate for which it was
designed.
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18. Do not use tool if switch does not turn it on or off. Any power tool that
cannot be controlled with the switch is dangerous and must be repaired.
19. Disconnect the plug from the power source and/or the battery pack from
the power tool before making any adjustments, changing accessories, or
storing power tools. Such preventive safety measures reduce the risk of
starting the power tool accidentally.
20. Store idle power tools out of the reach of children and do not allow
persons unfamiliar with the power tool or these instructions to operate
the power tool. Power tools are dangerous in the hands of untrained users.
21. Maintain power tools. Check for misalignment or binding of moving parts,
breakage of parts and any other condition that may affect the power
tool’s operation. If damaged, have the power tool repaired before use.
Many accidents are caused by poorly maintained power tools.
22. Keep cutting tools sharp and clean. Properly maintained cutting tools with
sharp cutting edges are less likely to bind and are easier to control.
23. Use the power tool, accessories and tool bits etc. in accordance with
these instructions, taking into account the working conditions and the
work to be performed. Use of the power tool for operations different from
those intended could result in a hazardous situation.
Service
24. Have your power tool serviced by a qualified repair person using only
identical replacement parts. This will ensure that the safety of the power tool
is maintained.
VOLTAGE WARNING:
Before connecting the machine to a power source (receptacle, outlet, etc.), be sure
the voltage supplied is the same as that specified on the nameplate of the machine.
A power source with voltage greater than that specified for the machine can result
in SERIOUS INJURY to the user, as well as damage to the machine. If in doubt,
DO NOT PLUG IN THE MACHINE. Using a power source with voltage less than
nameplate rating is harmful to the motor.
SPECIFICATIONS
Rated Power Input
400 W
Rated Speed
27000r/min
Max. Grinding Wheel Diameter
Ø25 mm
Max. Collet Size
6 mm
Net Weight
1.8 kg
※Due to the continuing program of research and development, the specifications herein
are subject to change without prior notice.
ADDITIONAL SAFETY RULES
1. Use only wheel points having a maximum operating speed at least as high as
“No-Load Speed” marked on the tool’s nameplate.
2. Check the wheel point carefully for cracks or damage before operation. Replace
cracked or damaged wheel point immediately. Run the tool at no load for about a
minute, holding tool away from others. If wheel is flawed, it will likely separate during
this test.
3. Hold the tool firmly.
4. Keep hands away from rotating parts.
5. Make sure the wheel point is not contacting the workpiece before the switch is turned
on.
6. Before using the tool on an actual workpiece, let it run for more than one minute.
(When mounting a new wheel point, let it run for more than three minutes.) Watch for
vibration or wobbling that could indicate poor installation or poorly balanced wheel
point.
7. Watch out for flying sparks. Hold the tool so that sparks fly away from you and other
persons or flammable materials.
8. Do not leave the tool running. Operate the tool only when hand-held.
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9. Always be sure you have a firm footing. Be sure no one is below when using
the tool in high locations.
10.Do not use water or grinding lubricant.
11.Do not use this tool as cutter.
12.Do not touch the workpiece immediately after operation, it may be extremely
hot and could burn your skin.
13.ALWAYS wear proper apparel including long sleeve shirts, leather gloves and
shop aprons to protect skin from contact with hot grindings.
14.Use of this tool to grind or sand some products, paints and wood could expose
user to dust containing hazardous substances. Use appropriate respiratory
protection.
SAVE THESE INSTRUCTIONS.
WARNING! MISUSE or failure to follow the safety rules stated in this
instruction manual may cause serious personal injury.
INSTRUCTIONS FOR OPERATION
Installing or Removing the Wheel Point
CAUTION:
Always be sure that the tool is switched off and unplugged before installing or
removing the wheel point.
Loosen the collet nut and insert the
wheel point into the collet nut. Use the
smaller wrench to hold the spindle and
use the larger one to tighten the collet
nut securely. (Fig. 1)
The wheel point should not be mounted
more than 10 mm from the collet nut.
Exceeding this distance could cause
vibration or a broken shaft. (Fig. 2)
To remove the wheel point, follow the
installation procedures in reverse.
Switch Operation
To start the tool, push the switch lever to the
“ON” position. To stop, push the switch lever
to the “OFF” position. (Fig. 3)
Operation
Turn the tool on without the wheel point
making any contact with the workpiece and
wait until the wheel point attains full speed.
Then apply the wheel point to the workpiece
gently. To obtain a good finish, hold the tool
with two hands and move the tool in the
leftward direction slowly. (Fig. 4)
CAUTION:
Apply light pressure on the tool. Excessive
pressure on the tool will only cause a poor finish and overloading of the motor.
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Dressing Wheel Point
When the wheel point becomes
“loaded” with various bits and
particles, you should dress the wheel
point with dressing stone. (Fig. 5)
MAINTENANCE AND INSPECTION
CAUTION:
Always be sure that the tool is switched off and unplugged before carrying out any
work on the tool.
1. 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.
Failure to do so could result in serious hazard.
2. 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.
3. Cleaning the Motor Vents
Keep the motor vents clean.
Clean the vents regularly or
when dusts accumulated on
them. (Fig. 6)
4. Inspecting and replacing the carbon brushes
Remove and check the carbon brushes
regularly. Replace when they wear down
to the limit mark (Fig. 7).
Keep the carbon brushes clean and free
to slip in the holders. Both carbon
brushes should be replaced at the same
time. Use only identical carbon brushes.
※Damaged cord must be replaced by a special cord purchased from authorized service
center.
※To maintain product SAFETY and RELIABILITY, repairs, any other maintenance or
adjustment should be performed by authorized centers, always using original replacement
parts.
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EXPLANATION OF GENERAL VIEW
1
Collet Nut
26
Brush Holder Cap
2
Collet
27
Carbon Brush
3
Collet Retainer
28
Carbon Brush Holder
4
Drive Spindle
29
Motor Housing
7
Ball Bearing 6000ZZ/C4
30
Nameplate
8
Circlip for Shaft 10
31
Rear Cover A
9
Barrel
32
Pan Head Tapping Screw ST4.2×19
10
Pan Head Tapping Screw ST5×23
33
Pan Head Tapping Screw ST4×37
11
Circlip for Shaft 10
35
Switch
12
Ball Bearing 6200ZZ/C4
36
Pan Head Tapping Screw ST4×22
13
Wave Spring Washer 25
37
Rear Cover B
14
Circlip for Hole 30
39
Cord
15
Coupling
40
Pan Head Tapping Screw ST4.2×16
(with Flat Washer)
16
Pan Head Screw M4×10
41
Strain Relief
17
Bearing Retainer
42
Cord Guard
18
Ball Bearing 608ZZ
43
Terminal Block
19
Inner Cover
44
O Ring （5.6×1.5）
20
Armature Assembly
45
Wire 105
21
Insulation Washer
46
Wire 120
22
Ball Bearing 608ZZ
47
Wire Assembly
23
Bearing Cover (22×24×9.2）
48
Capacitor
24
Pan Head Tapping Screw ST4.2
×65
861
Wrench
25
Stator Assembly
862
Collet
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