DeWalt 399080-02 User manual

399080-02 rev 11/15/02 10:13 AM Page 1

DEWALT Industrial Tool Co., 701 East Joppa Road, Baltimore, MD 21286 Printed in USA (NOV02-CD-2)
Form No. 399080-02 D28474, D28493, D28494, D28499, D28497
Copyright © 2002
The following are trademarks for one or more DEWALT power tools: the yellow and black color scheme; the “D” shaped air intake grill; the
array of pyramids on the handgrip; the kit box configuration; and the array of lozenge-shaped humps on the surface of the tool.
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D28474/D28493/D28494/D28499 Heavy Duty Large Angle Grinders
Grandes rectifieuses coudées de service intensif
Esmeriladoras de ángulo grande para trabajo pesado
D28497 Heavy Duty Large Angle Sander
Grandes ponceuse coudées de service intensif
Lijadora angular grande para trabajo pesado
INSTRUCTION MANUAL
GUIDE D'UTILISATION
MANUAL DE INSTRUCCIONES
INSTRUCTIVO DE OPERACIÓN, CENTROS DE SERVICIOY PÓLIZA
DE GARANTÍA. ADVERTENCIA: LÉASE ESTE INSTRUCTIVO
ANTES DE USAR EL PRODUCTO.
Questions? See us on the World Wide Web at www.dewalt.com
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English
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1
General Safety Instructions
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 THESE INSTRUCTIONS
WORK AREA
Keep your work area clean and well lit. Cluttered benches
and dark areas invite accidents.
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.
Keep bystanders, children, and visitors away while oper-
ating a power tool. Distractions can cause you to lose control.
ELECTRICAL SAFETY
Grounded tools must be plugged into an outlet properly
installed and grounded in accordance with all codes and
ordinances. Never remove the grounding prong or modify
the plug in any way. Do not use any adapter plugs. Check
with a qualified electrician if you are in doubt as to whether
the outlet is properly grounded.
If the tools should electrically malfunction or break down, ground-
ing provides a low resistance path to carry electricity away from
the user.This tool uses grounded construction (3 prong plug) to
provide a means to transfer electrical energy safely away from the
user in the event the tool electrically malfunctions, breaks down,
or the tool case becomes live. Damage to, or loss of, one of the
3 plug blades; damage to the plug or cord, or failure to have the
tool plugged into a verified and continuously grounded electrical
system, may result in electric shock, serious injury, or death. To
avoid these risks of injury, the tool must, at all times, be main-
tained and in proper working order (cord, plug blades) and
plugged into a continuously grounded electrical system. (See
also “Cleaning” in the Maintenance section, page 15.)
Avoid body contact with grounded surfaces such as pipes,
radiators, ranges and refrigerators. There is an increased
risk of electric shock if your body is grounded.
Don’t expose power tools to rain or wet conditions. Water
entering a power tool will increase the risk of electric shock.
Do not abuse the cord. Never use the cord to carry the
tools or pull the plug from an outlet. Keep cord away from
heat, oil, sharp edges or moving parts.Replace damaged cords
immediately.Damaged cords increase the risk of electric shock.
When operating a power tool outside, use an outdoor exten-
sion cord marked “W-A” or “W.” These cords are rated for out-
door use and reduce the risk of electric shock.
Minimum Gage for Cord Sets
IF YOU HAVE ANY QUESTIONS OR COMMENTS ABOUT THIS
OR ANY DEWALT TOOL, CALL US TOLL FREE AT:
1-800-4-DEWALT (1-800-433-9258)
SAVE THESE INSTRUCTIONS!
150 ft.100 ft.
50 ft.
25 ft.
Minimum AWG
Total Length of Cord in Feet
120 V Power Supply
12 AWG14 AWG16 A
12 A
More
Than Not More
Than
not recommended
Tool Nameplate
Ampere Rating
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2
PERSONAL SAFETY
Stay alert, watch what you are doing and use common
sense when operating a power tool. Do not use tool while
tired or under the influence of drugs, alcohol, or medica-
tion. A moment of inattention while operating power tools may
result in serious personal injury.
Dress properly. Do not wear loose clothing or jewelry.
Contain long hair. Keep your hair, clothing, and gloves
away from moving parts. Loose clothes, jewelry, or long hair
can be caught in moving parts. Air vents often cover moving
parts and should also be avoided.
Avoid accidental starting. Be sure switch is off before plug-
ging in. Carrying tools with your finger on the switch or plugging
in tools that have the switch on invites accidents.
Remove adjusting keys or wrenches before turning the tool
on. A wrench or a key that is left attached to a rotating part of
the tool may result in personal injury.
Do not overreach. Keep proper footing and balance at all
times. Proper footing and balance enables better control of the
tool in unexpected situations.
Use safety equipment. Always wear eye protection. Dust
mask, non-skid safety shoes, hard hat, or hearing protection
must be used for appropriate conditions.
TOOL USE AND CARE
Use clamps or other practical way to secure and support
the workpiece to a stable platform. Holding the work by hand
or against your body is unstable and may lead to loss of control.
Do not force tool. Use the correct tool for your application.
The correct tool will do the job better and safer at the rate for
which it is designed.
Do not use tool if switch does not turn it on or off. Any tool
that cannot be controlled with the switch is dangerous and must
be repaired.
Disconnect the plug from the power source before making
any adjustments, changing accessories, or storing the
tool. Such preventative safety measures reduce the risk of
starting the tool accidentally.
Store idle tools out of reach of children and other untrained
persons. Tools are dangerous in the hands of untrained users.
Maintain tools with care. Keep cutting tools sharp and
clean. Properly maintained tools, with sharp cutting edges are
less likely to bind and are easier to control.
Check for misalignment or binding of moving parts, break-
age of parts, and any other condition that may affect the
tools operation. If damaged, have the tool serviced before
using. Many accidents are caused by poorly maintained tools.
Use only accessories that are recommended by the manu-
facturer for your model. Accessories that may be suitable for
one tool may become hazardous when used on another tool.
SERVICE
Tool service must be performed only by qualified repair per-
sonnel. Service or maintenance performed by unqualified per-
sonnel could result in a risk of injury.
When servicing a tool, use only identical replacement
parts. Follow instructions in the Maintenance section of this
manual. Use of unauthorized parts or failure to follow
Maintenance instructions may create a risk of electric shock or
injury.
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Specific Safety Rules for Grinders
Always use proper guard with grinding wheel. A guard protects
operator from broken wheel fragments and wheel contact.
Accessories must be rated for at least the speed recom-
mended on the tool warning label.Wheels and other accessories
running over rated speed can fly apart and cause injury.Refer to the
table below. Accessory ratings are above rated no-load tool speeds
because actual tool speeds may vary.
NOTE: The rated no load tool speed is printed on the name plate and
embossed on the gear case.
Hold tool by insulated gripping surfaces when performing an
operation where the cutting tool may contact hidden wiring or
its own cord. Contact with a “live” wire will make exposed metal
parts of the tool “live” and shock the operator.
Clean out your tool often, especially after heavy use. Dust and
grit containing metal particles often accumulate on interior surfaces
and could create a risk of serious injury, electric shock or elec-
trocution.
Before using, inspect recommended accessory for cracks or
flaws. If such a crack or flaw is evident, discard the accessory.The
accessory should also be inspected whenever you think the tool
may have been dropped.
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3
When starting the tool with a new or replacement wheel, or a
new or replacement wire brush installed, hold the tool in a well
protected area and let it run for one minute. If the wheel has an
undetected crack or flaw, it should burst in less than one minute.If the
wire brush has loose wires, they will be detected.Never start the tool
with a person in line with the wheel.This includes the operator.
In operation, avoid bouncing the wheel or giving it rough
treatment. If this occurs, stop the tool and inspect the wheel for
cracks and flaws.
Direct sparks away from operator, bystanders or flammable
materials. Sparks may be produced while using a sander or
grinder. Sparks may cause burns or start fires.
Always use side handle. Tighten the handle securely. The side
handle should always be used to maintain control of the tool at all
times.
Use extra care when grinding into a corner because a sudden,
sharp movement of the grinder may be experienced when the
wheel contacts a secondary surface.
Wear appropriate personal hearing protection during use.
Under some conditions and duration of use, noise from this product
may contribute to hearing loss.
WARNING: Some dust created by power sanding, sawing,
grinding, drilling, and other construction activities contains chem-
icals known to cause cancer, birth defects, or other reproductive
harm. Some examples of these chemicals are:
• lead from lead-based paints,
• crystalline silica from bricks and cement and other masonry
products, and
• arsenic and chromium from chemically-treated lumber (CCA).
5000 RPM
6000 RPM
8000 RPM
5500 RPM
6600 RPM
8500 RPM
Minimum
Accessory
Rating
Rated no
(no load)
Tool Speed
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Components
A. Trigger Switch B. Lock On Button
C. Spindle Lock D. Side Handle
E. Spindle F. Soft Mount
G. Rubber Bumper
Features
SWITCH
The tool is controlled by a trigger switch (A). A lock-on button (B)
provides increased comfort in extended use applications.
ROTATING REAR HANDLE (D28499 ONLY)
The rear handle can be positioned 30°, 60°, and 90° left and right
of center position.
ROTATING GEAR CASE (D28474, D28493, D28494, D28497)
For applications in which a tool will be dedicated for uses in edge
grinding and finishing work, the gear case may be rotated 90° left
or right of its original position. See page 8 for instructions on
rotating the gear case.
A
B
D
Your risk from these exposures varies, depending on how often you
do this type of work. To reduce your exposure to these chemicals:
work in a well ventilated area, and work with approved safety equip-
ment, such as those dust masks that are specially designed to filter
out microscopic particles.
•Avoid prolonged contact with dust from power sanding,
sawing, grinding, drilling, and other construction activities.
Wear protective clothing and wash exposed areas with soap
and water. Allowing dust to get into your mouth, eyes, or lay on the
skin may promote absorption of harmful chemicals.
• The label on your tool may include the following symbols. The
symbols and definitions are as follows:
V ............volts A ............amperes
Hz ..........hertz W............watts
min..........minutes ..........alternating current
........direct current no ..........no load speed
............Class II Construction ............earthing terminal
..........safety alert symbol .../min ....revolutions or
reciprocations
per minute
FAMILIARIZATION
Large Angle Grinders and Large Angle Sanders are designed for
heavy material removal in extended use applications.The following
grinders and sanders are described in this manual.
D28474 7" Angle Grinder 8,000 rpm
D28493 9" Angle Grinder 5,000 rpm
D28494 7"/9" Angle Grinder 6,000 rpm
D28497 7"/9" Angle Sander 6,000 rpm
D28499 7"/9" Angle Grinder 6,000 rpm
E
F
CG
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MULTIPLE SIDE HANDLE POSITIONS
The side handle can be properly positioned in five locations based
on personal preference and application. The side handle must be
used at all times to maintain proper control of the tool.
RUBBER BUMPER
The gear case rubber bumper may wear with
use. The bumper can be replaced with part
number 397711-00 available at extra cost
from DEWALT authorized service centers.
Replacement should be performed by
DEWALT authorized service centers or
qualified service personnel.
SPINDLE LOCK
The spindle lock pin is provided to prevent the
spindle from rotating when installing or removing
wheels. Operate the spindle lock pin only when
the tool is turned off and unplugged from the
power source. To engage the lock, depress the
spindle lock button (C) and rotate the spindle
until you are unable to rotate it further.
CAUTION: Never depress the spindle lock button while the grinder
is running. Never turn on the grinder while the spindle lock button is
depressed. Damage to your tool or personal injury may result.
SOFT MOUNT
The grinder is equipped with a soft mount, enabling easy wheel
installation and removal.
Accessories and Attachments
It is important to choose the correct guards, backing pads and
flanges to use with grinder accessories. See the chart on pages
5–7 for information on choosing the correct accessories.
C
Sanding Flap Discs
soft mount soft mount
Type 27 guard
D284937/D284939 Type 27 guard
D284937/D284939
hubbed sanding flap
disc
non-hubbed sanding
flap disc
clamp nut
22191-00
backing flange
54339-00
NOTE: Wheel size must match guard size;i.e., a new 7" wheel may
not be used with a 9" guard.The bottom surface of wheel must be
inside the bend of the guard lip.
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Grinding Wheels
soft mount
Type 27 guard
D284937/D284939
Type 27 hubbed wheel
soft mount
Type 28 guard
D284938
Type 28 hubbed wheel
soft mount
Type 27 guard
D284937/D284939
backing flange
54339-00
Type 27 non-hubbed
wheel
clamp nut
22191-00
soft mount
Type 28 guard
D284938
backing flange
54339-00
Type 28 non-hubbed
wheel
Sanding Discs
soft mount
rubber backing pad
DW4947
sanding disc
clamp nut
included with
D4947
clamp nut
22191-00
NOTE: Wheel size must match guard size;i.e., a new 7" wheel may not be used with a
9" guard.The bottom surface of wheel must be inside the bend of the guard lip.
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Flaring Cup Stones
Wire Wheels
soft mount
soft mount
wire cup brush
wire wheel
Type 11 flaring cup guard
D284934 — 4”
D284936 — 6”
backing flange
608368-00
flaring cup stone
NOTE: Wheel size must match guard size;i.e., a 7" wheel may not
be used with a 9" guard.
Cutting Wheels
Type 1 guard
D284931 Type 1 guard
D284931
abrasive cutting wheel diamond cutting wheel
clamp nut
608463-00 clamp nut
608463-00
Type 27 guard
D284937/D284939
Type 27 guard
D284937/D284939
backing flange
608370-00 backing flange
608370-00
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•Two rear positions: Rear handle positions
are designed for optimized balance in edge
grinding applications.
•One top position: Top handle position is
designed for edge grinding applications.
NOTE: D28497 includes only three handle
positions.
Rotating the Rear Handle
Turn off and unplug tool before making any adjustments or
removing or installing accessories. Before reconnecting the
tool, depress and release the trigger switch to ensure that the
tool is off.
1. Unlock the rear handle by
pulling out the Handle Re-
lease Lever (G) as shown.
2. Rotate handle into available
0°, 30°, 60°, or 90° position
left OR right of center.
3. Push in the handle release
lever.
4. Before turning the tool on, ensure that the handle is locked into
a position and the handle release lever has returned to the orig-
inal position flush with the tool housing.
Rotating the Gear Case
Turn off and unplug tool before making any adjustments or
removing or installing accessories. Before reconnecting the
tool, depress and release the trigger switch to ensure that the
tool is off.
1. Remove the four corner screws attaching the gear case to motor
housing.
CAUTION: Accessories must be rated for at least the speed
recommended on the tool warning label. Wheels and other acces-
sories running over rated speed can fly apart and cause injury.
ATTACHMENTS
Attachments designed specifically for this grinder can be
purchased through DEWALT dealers and DEWALT Factory
Service centers.
D284939 9" Type 27 guard
D284948 9" Type 28 guard
D284937 7" Type 27 guard
D284936 6" Type 11 Flaring cup guard with flange
D284934 4" Type 11 Flaring cup guard with flange
D284933 Type 11 flaring cup wheel backing flange
D284932 Type 1 Flange set
D284931 7" Type 1 Guard
054339-00 Grinding backing flange
22191-00 Clamp nut
61820-01 Wheel Wrench
445928-01 Soft mount spindle protector
397711-00 Rubber gear case bumper
ASSEMBLY AND ADJUSTMENTS
Attaching the Side Handle
To install the side handle, thread the handle into one of the five
positions listed below and tighten securely by turning clockwise.
•Two front positions: Forward handle positions are designed for
optimized balance in surface finishing applications.
G
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9
2.Without separating the gear case from motor housing, rotate the
gear case head to desired position.
NOTE: If the gear case and motor housing become separated by
more than 1/8", the tool must be serviced and re-assembled by a
DEWALT service center. Failure to
have the tool serviced may cause
brush, motor and bearing failure.
3. Re-install screws to attach the
gear case to the motor housing.
Tighten screws to 20 in lbs
torque. Overtightening could
cause screws to strip.
OPERATION
Power Source
Plug the Large Angle Grinder into a dedicated electrical circuit.
Operating this tool on a circuit with other tools will decrease tool
performance.
Switch
CAUTION: Before connecting the tool to a power source or after
a power failure, depress and release the trigger switch (A) once
without depressing the lock-on button (B) to
ensure that the switch is in the off position. If
the trigger switch is locked on, the tool will
start unexpectedly when power is reconnect-
ed to the tool. Hold the side handle and rear
handle firmly to maintain control of tool at
start up and during use.
TRIGGER OPERATION
To turn the tool on, depress the trigger switch (A). The tool will
remain running while the trigger is depressed. Turn the tool off by
releasing the trigger.
TRIGGER OPERATION WITH LOCK-ON FEATURE
To turn tool on, depress trigger. Depress and hold lock-on button
(B) while releasing trigger. Lock-on button will remain depressed
and tool will remain on.
To turn the tool off, depress and release trigger.The lock pin button
will pop out, permitting the trigger to disengage and causing the tool
to turn off.
NOTE: Allow the tool to reach full speed before touching tool to
work surface. Lift the tool from the work surface before turning the
tool off.
CAUTION: Make sure the wheel has come to a complete stop
before setting the tool down.
REMOVAL OF LOCK-ON FEATURE
The lock-on button can be permanently removed without compro-
mising compliance with regulatory agencies shown on the tool’s
nameplate. Removal of the lock pin must be done by a DEWALT
Service Center.
Mounting and Using Depressed Center
Grinding Wheels and Sanding Flap
Discs
MOUNTING AND REMOVING GUARD
Turn off and unplug tool before making any adjustments or
removing or installing accessories. Before reconnecting the
tool, depress and release the trigger switch to ensure that the
tool is off.
90˚ 90˚
A
B
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IMPORTANT INFORMATION ABOUT
GUARDS
Guards must be used with all grinding wheels,
sanding flap discs, wire brushes and wire
wheels.The tool may be used without a guard
only when sanding with conventional sanding
discs. DEWALT models D28493, D28494,
D28474, D28499 are provided with a guard
intended for use with depressed center wheels
(Type 27), and hubbed grinding wheels (Type
27). The same guard is designed for use with sanding flap discs,
wire brushes and wire wheels. Grinding and cutting with wheels
other than Type 27 and 29 require different accessory guards not
included with the tool. Mounting instructions for these accessory
guards are included in the accessory package.
CAUTION: When using a grinding wheel with a Type 27, 28, or
29 guard, be sure that the bottom surface of the grinding wheel is
inside the the guard lip.
CAUTION:DEWALT model D28497 Angle Sander may only be
used for grinding by using appropriate accessory guard.
1. Open the guard latch (H), and align
the lugs with slots on the gear case
cover. Position the guard facing back-
ward, as shown.
2. Push the guard down until the guard
lugs engage and rotate freely in the
groove on the gear case hub.
3. With the guard latch open, rotate the guard into the desired
working position that provides maximum protection to the user
as shown.
4. Close the guard latch to secure the
guard on the gear case.You should be
unable to rotate the guard by hand
when the latch is closed.Do not oper-
ate the grinder with a loose guard or
the clamp lever in open position.
5. To remove the guard, follow the proce-
dure above in reverse order.
NOTE: The guard is pre-adjusted to the
diameter of the gear case hub at the factory.
If, after a period of time, the guard becomes
loose, tighten the adjusting screw (I) with
clamp in the closed position.
CAUTION: Do not tighten the adjusting screw with the clamp
lever in open position. Undetectable damage to the guard or the
mounting hub may result.
MOUNTING AND REMOVING HUBBED WHEELS
Hubbed wheels install directly on the 5/8" — 11 threaded spindle.
1. Thread the wheel on the spindle by hand, seating the wheel
against the soft mount.
2. Depress the spindle lock button and use a wrench to tighten the
hub of the wheel.
3. Reverse the above procedure to remove the wheel.
CAUTION: Failure to properly seat the wheel against the soft
mount before turning the tool on may result in damage to the tool
or the wheel.
MOUNTING NON-HUBBED WHEELS
Depressed center, Type 27 grinding wheels must be used with
available accessory flanges. See the chart on pages 5–7 of this
manual for more information.
H
I
GRINDING
WHEEL
SURFACE
GUARD
LIP
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1. Install the metal backing flange (J) on spindle
(E) against the soft mount.
2. Place wheel against the backing flange, cen-
tering the wheel on the backing flange pilot.
3. While depressing the spindle lock button,
thread the clamp nut (K) on spindle, piloting
the raised hub on clamp nut in the center of
grinding wheel.
4. Tighten the clamp nut with a wrench.
5. Reverse the above procedure to remove the
wheel.
SURFACE GRINDING WITH GRINDING WHEELS
1. Allow the tool to reach full speed before touching tool to work
surface.
2. Apply minimum pressure to work surface, to allow the tool to
operate at high speed.
3. Maintain a 20˚ to 30˚ angle between the tool
and work surface.
4. Continuously move the tool in a forward and back motion to
avoid creating gouges in the work surface.
5. Remove the tool from work surface before turning tool off.Allow
the tool to stop rotating before setting it down.
EDGE GRINDING WITH GRINDING WHEELS
CAUTION: Wheels used for cutting and edge grinding may break
if they bend or twist while the tool is being used to do cut-off work or
deep grinding. To reduce the risk of serious injury, limit the use of
these wheels with a standard Type 27 guard to shallow cutting and
notching (less than 1/2" in depth).The open side of the guard must
be positioned away from the operator.For deeper cutting with aType
1 wheel, use a closed, Type 1 guard. Type 1 guards
are available at extra cost from your local dealer or authorized
service center.
1. Allow the tool to reach full speed before touching the tool to the
work surface.
2. Apply minimum pressure to work surface, to allow the tool to
operate at high speed.
3. Protect yourself during edge finishing by directing the open side
of the guard away from you.
4. Move the tool continuously in a forward and back motion to avoid
creating gouges in the work surface.
5. Remove tool from work surface before turning the tool off.Allow
the tool to stop rotating before setting it down.
WARNING: Do not use edge grinding wheels for surface grind-
ing applications because edge grinding wheels are not designed for
side pressures encountered with surface grinding.Wheel breakage
and injury may result.
SURFACE FINISHING WITH SANDING FLAP DISCS
1. Allow the tool to reach full speed before touching tool to work
surface.
2. Apply minimum pressure to work surface, to allow the tool to
operate at high speed.
3. Maintain a 5˚ to 10˚ angle between the tool
and work surface.
4. Continuously move the tool in a forward and back motion to
avoid creating gouges in the work surface.
5. Remove the tool from work surface before turning tool off.Allow
the tool to stop rotating before setting it down.
5˚- 10˚
J
E
K
20˚- 30˚
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Mounting and Using Sanding
Backing Pads
Sanding pads and sanding discs must be rated above minimum
accessory speed as shown on tool.Recommended sanding back-
ing pads and sanding discs are available at extra cost from
DEWALT service centers and DEWALT dealers.
NOTE: Guard may be removed for sanding applications with
backing pads and sanding discs.Sanding flap discs are considered
grinding wheels by ANSI standards and require the use of a guard.
(See Mounting and Using Depressed Center Grinding Wheels and
Sanding Flap Discs).
MOUNTING SANDING BACKING PADS
Turn off and unplug tool before making any adjustments or
removing or installing accessories. Before reconnecting the
tool, depress and release the trigger switch to ensure that the
tool is off.
CAUTION: Proper guard must be re-installed for grinding wheel,
sanding flap disc, wire brush, or wire wheel applications after sand-
ing applications are complete.
1. Place or appropriately thread rubber backing
pad (L) down to soft mount.
2. Place the sanding disc (M) on the rubber
backing pad (L).
3. While depressing spindle lock, thread clamp
nut (N) on spindle, piloting the raised hub on
the clamp nut into the center of sanding disc
and backing pad.
4. Tighten the clamp nut with the proper
wrench.
5. To remove the wheel, reverse the above procedure.
USING SANDING BACKING PADS
Choose the proper grit sandpaper for your application. Sandpaper
is available in various grits. Coarse grits yield faster material
removal rates and a rougher finish. Finer grits yield slower material
removal and a smoother finish.
Begin with coarser grit discs for fast, rough material removal.Move
to a medium grit paper and finish with a fine grit disc for optimal
finish. Coarse 16 – 30 grit
Medium 36 – 80 grit
Fine Finishing 100 – 120 grit
Very Fine Finishing 150 – 180 grit
1. Allow the tool to reach full speed before touching tool to work
surface.
2. Apply minimum pressure to work surface, allowing tool to oper-
ate at high speed.
3. Maintain a 5˚ to 15˚ angle between the tool
and work surface. The sanding disc should
contact approximately one inch of work sur-
face.
4. Move the tool constantly in a straight line to prevent burning and
swirling of work surface.Allowing the tool to rest on the work sur-
face without moving, or moving the tool in a circular motion
causes burning and swirling marks on the work surface.
5. Remove the tool from the work surface before turning the tool
off.Allow the tool to stop rotating before setting it down.
5˚-15˚
N
L
M
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Mounting and Using Wire Brushes
and Wire Wheels
Turn off and unplug tool before making any adjustments or
removing or installing accessories. Before reconnecting the
tool, depress and release the trigger switch to ensure that the
tool is off.
Wire brushes and wire wheels must be rated above minimum
accessory speed as shown on tool. Use only wire brushes and
wheels provided with a 5/8" – 11 threaded hub. A Type 27 guard is
required when using wire brushes and wheels.
CAUTION: Wear work gloves when handling wire brushes or
wheels.Wire brushes and wheels can become sharp.
MOUNTING WIRE BRUSHES AND WIRE WHEELS
1. Thread the wheel on the spindle by hand, seating the wheel
against the soft mount.
2. Depress the spindle lock button and use a wrench on the hub of
the wire brush or wheel to tighten the wheel.
3. To remove the wheel, depress the spindle lock button and use a
wrench on the hub of the wire brush or wheel to loosen it.
NOTE: Failure to properly seat the wheel hub against the soft
mount before turning the tool on may result in damage to the tool
or wheel.
USING WIRE CUP BRUSHES AND WIRE WHEELS
Wire wheels and brushes can be used for removing rust, scale and
paint, and for smoothing irregular surfaces.
1. Allow tool to reach full speed before touching tool to work
surface.
2. Apply minimum pressure to work surface, to allow the tool to
operate at high speed.
3. Maintain a 5˚ to 10˚ angle between the tool
and work surface for wire cup brushes.
4. Maintain contact between the edge of the
wheel and the work surface with wire
wheels.
5. Continuously move the tool in a forward and back motion to
avoid creating gouges in the work surface.Allowing the tool to
rest on the work surface without moving, or
moving the tool in a circular motion causes
burning and swirling marks on the work
surface.
6. Remove the tool from the work surface
before turning the tool off. Allow the tool to
stop rotating before setting it down.
Mounting and Using Flaring Cup
(Type 11) Wheel
MOUNTING FLARING CUP WHEEL GUARD
WARNING: The flaring cup wheel guard is not included with
this tool. Flaring cup wheels require proper flanges and guards.
4" flaring cup wheel guard D284934 and 6" flaring cup wheel
guard D284936 are available as accessories and include proper
flange. Failure to use the proper flange and guard can result in
injury resulting from wheel breakage and wheel contact.
Turn off and unplug tool before making any adjustments or
removing or installing accessories. Before reconnecting the
tool, depress and release the trigger switch to ensure that the
tool is off.
1. Install the guard as shown.
2. Guard body should be positioned between the spindle and the
operator to provide maximum operator protection.
5˚-10˚
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14
3. Securely tighten the two clamping
screws (W) supplied with the guard.
MOUNTING FLARING CUP WHEEL
1. Remove the soft mount (F).
2. Install the flaring cup wheel backing
flange, aligning the flats on spindle (O)
with the flats on backing flange (P).
3. Thread the flaring cup wheel on spindle by hand, seating wheel
against backing flange.
4. Depress the spindle lock button and tighten the wheel by hand.
5. To remove the wheel, reverse the above procedure.
CAUTION: Failure to properly seat the wheel against backing
flange before turning the tool on may result in damage to the tool or
the wheel.
NOTE: Adjust the guard skirt so that only 1/8" of the wheel is
exposed by loosening the bolts, allowing the guard to lengthen.
Tighten the guard skirt bolts securely before using the grinder.
USING A FLARING CUP WHEEL
Flaring cup wheels are designed for heavy material removal.
1. Allow the tool to reach full speed before touching tool to work
surface.
2. Apply minimum pressure to work surface, allowing the tool to
operate at high speed.
3. Maintain a 5˚ to 10˚angle between the tool and
the work surface.
4. Continuously move the tool in a forward and
back motion to avoid creating gouges in the work surface.
5. Remove the tool from work surface before turning tool off.Allow
the tool to stop rotating before setting it down.
Mounting and Using Cutting
(Type 1) Wheels
Cutting wheels include diamond wheels and abrasive discs.
Abrasive cutting wheels for metal and concrete use are available.
Diamond blades for concrete cutting can also be used.
WARNING: A closed, cutting wheel guard is not included with this
tool. Cutting wheels require proper flanges and guards. A 7" cutting
guard, D284931, is available as an accessory and includes proper,
matching flanges. Failure to use proper flange and guard can result
in injury resulting from wheel breakage and wheel contact.
MOUNTING CLOSED (TYPE 1) GUARD
Turn off and unplug tool before making any
adjustments or removing or installing
accessories. Before reconnecting the tool,
depress and release the trigger switch to
ensure that the tool is off.
1. Open the guard latch (H), and align the lugs
with slots on the gear case cover. Position
the guard facing backward, as shown.
2. Push the guard down until the guard lug
engages and rotates freely in the groove on
the gear case hub.
3. Rotate guard (Q) into desired working posi-
tion. The guard body should be positioned
H
Q
5˚-10˚
FOP
W
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15
between the spindle and the operator to provide maximum oper-
ator protection.
4. Close the guard latch to secure the guard on the gear case
cover.You should be unable to rotate the guard by hand when
the latch is in closed position. Do not operate grinder with a
loose guard or clamp lever in open position.
NOTE:The guard is pre-adjusted to the diamet-
er of the gear case hub at the factory. If, after a
period of time, the guard becomes loose, tight-
en the adjusting screw (I) with the clamp lever
in the closed position.
CAUTION: Do not tighten adjusting screw with clamp lever in
open position.Undetectable damage to guard or mounting hub may
result.
MOUNTING CUTTING WHEELS
1. Remove Soft Mount (F).
2. Install wheel backing flange, aligning flats on spindle (O) with
flats on backing flange (R).
3. Place the wheel on the backing flange, centering the wheel on
the backing flange pilot.
4. Install the clamp nut, ensuring that the wheel remains centered
on the backing flange.
5. Depress the spindle lock button and tighten clamp nut with
wrench.
6. Reverse the above procedure to remove the wheel.
USING CUTTING WHEELS
1. Allow tool to reach full speed before touching tool to work
surface.
2. Apply minimum pressure to work surface, allowing tool to oper-
ate at high speed.
3. Once you begin a cut, maintain the angle of the cutting wheel to
the work surface. This will keep you from bending the wheel
which could result in wheel breakage and injury.
4. Remove the tool from work surface before turning tool off.Allow
the tool to stop rotating before setting it down.
MAINTENANCE
Cleaning
WARNING: Blowing dust and grit out of the motor housing using
clean, dry compressed air is a necessary regular maintenance pro-
cedure.Dust and grit containing metal particles often accumulate on
interior surfaces and could create an electrical shock or electrocu-
tion if not frequently cleaned out. ALWAYS WEAR SAFETY
GLASSES.
CAUTION: Never use solvents or other harsh chemicals for
cleaning the non-metallic parts of the tool.Use a clean, dry rag only.
Lubrication
DEWALT tools are properly lubricated at the factory and are ready
for use.
FO
R
I
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Repairs
To assure product SAFETY and RELIABILITY, repairs, mainte-
nance and adjustment should be performed by authorized service
centers or other qualified service personnel. Always use identical
replacement parts.
Motor Brushes
When brushes become worn, the tool will automatically stop, pre-
venting damage to the motor. Brush replacement should be per-
formed by DEWALT authorized service centers or other qualified
service personnel. Qualified service personnel should follow the
procedures below when replacing motor brushes.
Turn off and unplug tool before making any adjustments or
removing or installing accessories. Before reconnecting the
tool, depress and release the trigger switch to ensure that the
tool is off.
1. Remove the brush doors located on the sides of motor housing.
2. To remove the brush, hold the female terminal, which is attached
to the brush lead wire, and disconnect the female terminal from
the male terminal.
3. Pull the brush straight up out of the brush holder.
4. Replace brushes, in pairs, with original DEWALT brushes avail-
able from DEWALT authorized service centers.
5. Ensure that the brushes slide freely in brush box.
6. Reconnect the brush lead wire to brush box terminal.
7. Re-install the brush doors before using the tool.Torque screws to
10 in-lbs, maximum.Overtightening may cause screws to strip.
Purchasing Accessories
Recommended accessories for use with your tool are available at
extra cost from you local dealer or authorized service center.If you
need assistance in locating any accessory for your tool, contact:
DEWALT Industrial Tool Co., 701 East Joppa Road, Baltimore, MD
21286.
CAUTION:The use of any other accessory not recommended for
use with this tool could be hazardous.
Full Warranty
DEWALT heavy duty industrial tools are warranted for one year
from date of purchase. We will repair, without charge, any defects
due to faulty materials or workmanship. For warranty repair infor-
mation, call 1-800-4-DEWALT. This warranty does not apply to
accessories or damage caused where repairs have been made or
attempted by others. This warranty gives you specific legal rights
and you may have other rights which vary in certain states or
provinces.
In addition to the warranty, DEWALT tools are covered by our:
30 DAY NO RISK SATISFACTION GUARANTEE
If you are not completely satisfied with the performance of your
DEWALT heavy duty industrial tool, simply return it to the participat-
ing seller within 30 days for a full refund.Please return the complete
unit, transportation prepaid. Proof of purchase may be required.
FREE WARNING LABEL REPLACEMENT: If your warning labels
become illegible or are missing, call 1-800-4-DEWALT for a free
replacement.To request replacement labels, you will need to know
the rated rpm of your tool.The rpm of your tool is stamped into the
tool housing.
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