DeWalt DWE4120 Guide D'utilisation page 9

Spindle Lock (Fig. I)
The spindle lock button 1
spindle from rotating when installing or removing wheels.
Operate the spindle lock only when the tool is turned off,
unplugged from the power supply, and has come to a
complete stop. Do not engage the spindle lock button
while the tool is operating because damage to the tool will
result. To engage the lock, depress the spindle lock button
and rotate the spindle until you are unable to rotate the
spindle further.
Mounting and Using Depressed Center Grinding
Wheels and Sanding Flap Discs
Mounting and Removing Hubbed Wheels
(Fig. J)
Hubbed wheels install directly on the 5/8"-11 threaded
spindle. Thread of accessory must match thread of spindle.
1. Remove backing flange
2. Thread the wheel on the spindle
3. Depress the spindle lock button and use a wrench to
tighten the hub of the wheel.
4. Reverse the above procedure to remove the wheel.
NOTICE: Failure to properly seat the wheel before turning the
tool on may result in damage to the tool or the wheel.
Mounting Non-Hubbed Wheels (Fig. J)
Depressed center Type 27 grinding wheels must be
used with included flanges. Refer to Accessories and
Attachments for more information.
1. Install the backing flange
section (pilot) against the wheel. Be sure the backing flange
recess is seated onto the flats of the spindle by pushing and
twisting the flange before placing wheel.
2. Place wheel against the backing flange, centering the
wheel on the raised section (pilot) of the backing flange.
3. While depressing the spindle lock button, thread the
clamp nut 5 on spindle. If the wheel you are installing is
more than 1/8" (3.17 mm) thick, place the threaded clamp
nut on the spindle so that the raised section (pilot) fits into
the center of the wheel. If the wheel you are installing is
1/8" (3.17 mm) thick or less, place the threaded clamp nut
on the spindle so that the raised section (pilot) is not against
the wheel.
4. While depressing the spindle lock button, tighten the
clamp nut with a wrench.
5. To remove the wheel, depress the spindle lock button
and loosen the threaded clamp nut with a wrench.
1/4" WhEEls
(6.35 mm)
Clamp Nut
Backing Flange
nOTE: If the wheel spins after the clamp nut is tightened,
check the orientation of the threaded clamp nut. If a thin
wheel is installed with the pilot on the clamp nut toward
the wheel, it will spin because the height of the pilot
prevents the clamp nut from holding the wheel.
is provided to prevent the
4 by pulling away from the tool.
by hand.
2
4 on spindle 2 with the raised
1/8" WhEEls
(3.17 mm)
Clamp Nut
Backing Flange
Surface Grinding with Grinding Wheels (Fig. K)
1. Allow the tool to reach full speed before touching the
tool to the work surface.
2. Apply minimum pressure to the work surface, allowing
the tool to operate at high speed. Grinding rate is greatest
when the tool operates 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 laying it down.
Edge Grinding with Grinding Wheels (Fig. L)

WARNING: 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 a Type 1 cut‑off
wheel, use a closed, Type 1 guard. Refer to the Accessories
Chart for more information. 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 the work surface, allowing
the tool to operate at high speed. Grinding rate is greatest
when the tool operates at high speed.
3. Position yourself so that the open-underside of the
wheel is facing away from you.
4. Once a cut is begun and a notch is established in the
workpiece, do not change the angle of the cut. Changing
the angle will cause the wheel to bend and may cause
wheel breakage. Edge grinding wheels are not designed to
withstand side pressures caused by bending.
5. Remove the tool from the work surface before turning
the tool off. Allow the tool to stop rotating before laying
it down.

WARNING: Do not use edge grinding/cutting wheels for
surface grinding applications if the wheel label has forbidden
such use because these wheels are not designed for side
pressures encountered with surface grinding. Wheel breakage
and serious personal injury may result.
Surface Finishing with Sanding Flap Discs
(Fig. M)
1. Allow the tool to reach full speed before touching the
tool to the work surface.
2. Apply minimum pressure to work surface, allowing the
tool to operate at high speed. Sanding rate is greatest when
the tool operates 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 laying it down.
Mounting Sanding Backing Pads (Fig. N)

WARNING: Proper guard must be reinstalled for
grinding wheel, sanding flap disc, wire brush or wire wheel
applications after sanding applications are complete.
English
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