DeWalt DCF850 Guide D'utilisation page 7

To install an accessory, fully insert the accessory. The
accessory is locked into place (Fig. H).
To remove an accessory, pull the chuck collar
from the front of the tool. Remove the accessory (Fig. H).
OPERATION

WARNING: To reduce the risk of serious personal
injury, turn unit off and remove the battery pack
before making any adjustments or removing/installing
attachments or accessories. An accidental start‑up can
cause injury.
Installing and Removing the Battery Pack (Fig. F)
nOTE: For best results, make sure your battery pack is
fully charged.
To install the battery pack
battery pack with the rails inside the tool's handle and slide
it into the handle until the battery pack is firmly seated in
the tool and ensure that it does not disengage.
To remove the battery pack from the tool, press the release
button and firmly pull the battery pack out of the tool
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handle. Insert it into the charger.
Proper Hand Position (Fig. G)

WARNING: To reduce the risk of serious personal injury,
ALWAYS use proper hand position as shown.

WARNING: To reduce the risk of serious personal injury,
ALWAYS hold securely in anticipation of a sudden reaction.
Proper hand position requires one hand on the main
handle .
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Variable Speed Trigger and Forward/Reverse
Control Button (Fig. A)
The tool is turned on and off by pulling and releasing
the variable speed trigger
depressed, the higher the speed of the tool. Your tool is
equipped with a brake. The chuck will stop as soon as the
trigger switch is fully released.
A forward/reverse control button
rotational direction of the tool and also serves as a
lock-off button.
• To select forward rotation (clockwise), release the trigger
and depress the forward/reverse control button on the right
side of the tool.
• To select reverse (counterclockwise), depress the forward/
reverse control button on the left side of the tool.
nOTE: The center position of the control button locks the
tool in the off position. When changing the position of the
control button, be sure the trigger is released.
nOTE: Continuous use in variable speed range is not
recommended. It may damage the switch and should
be avoided.
nOTE: The first time the tool is run after changing the
direction of rotation, you may hear a click on start up. This is
normal and does not indicate a problem.
Worklights (Fig. A)

CAUTION: Do not stare into worklight. Serious eye
injury could result.
There are three worklights
collar . The worklights are activated when the trigger
5
switch is depressed. When the trigger is released, the
5 away
1 into the tool handle, align the
. The farther the trigger is
3
4 determines the
8 located around the chuck
worklight will stay illuminated for up to 20 seconds. If
the trigger switch remains depressed, the worklights will
remain on.
nOTE: The worklights are for lighting the immediate work
surface and are not intended to be used as a flashlight.
Usage (Fig. A)

CAUTION: Ensure fastener and/or system will withstand
the level of torque generated by the tool. Excessive torque may
cause breakage and possible personal injury.
1. Place the accessory on the fastener head. Keep the tool
pointed straight at the fastener.
2. Press variable speed trigger switch
Release variable speed trigger switch to stop operation.
Always check torque with a torque wrench, as the fastening
torque is affected by many factors including the following:
‑ Voltage: Low voltage, due to a nearly discharged battery,
will reduce fastening torque.
‑ Accessory size: Failure to use the correct accessory size
will cause a reduction in fastening torque.
‑ Bolt size: Larger bolt diameters generally require higher
fastening torque. Fastening torque will also vary according
to length, grade, and torque coefficient.
‑ Bolt: Ensure that all threads are free of rust and other
debris to allow proper fastening torque.
‑ Material: The type of material and surface finish of the
material will affect fastening torque.
‑ Fastening time: Longer fasten ing time results in
increased fastening torque. Using a longer fastening
time than recommended could cause the fasteners to be
overstressed, stripped or damaged.
MAINTENANCE

WARNING: To reduce the risk of serious personal
injury, turn unit off and remove the battery pack
before making any adjustments or removing/installing
attachments or accessories. An accidental start‑up can
cause injury.
Your D WALT power tool has been designed to operate
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over a long period of time with a minimum of maintenance.
Continuous satisfactory operation depends upon proper
tool care and regular cleaning.
Cleaning

WARNING: Blow dirt and dust out of all air vents with
clean, dry air at least once a week. To minimize the risk of eye
injury, always wear ANSI Z87.1 approved eye protection when
performing this procedure.

WARNING: Never use solvents or other harsh chemicals
for cleaning the non‑metallic parts of the tool. These
chemicals may weaken the plastic materials used in these
parts. Use a cloth dampened only with water and mild soap.
Never let any liquid get inside the tool; never immerse any part
of the tool into a liquid.
Accessories

WARNING: Since accessories, other than those offered by
D WALT, have not been tested with this product, use of such
e
accessories with this product could be hazardous. To reduce the
risk of injury, only D WALT recommended accessories should be
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used with this product.
Recommended accessories for use with your product are
available at extra cost from your local dealer or authorized
service center. If you need assistance in locating any
English
to start operation.
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