Maintenance - DeWalt DCF850N-XJ Original Instructions Manual

tool. The centre position of the control button locks the trigger
switch in the off position. When changing the position of the
control button, be sure the trigger is released.
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)
There are three worklights
chuck 4 . The worklights are activated when the trigger switch
is depressed.
When the trigger is released, the worklight will stay illuminated
for up to 20 seconds.
nOTE: The worklights are for lighting the immediate work
surface and are not intended to be used as a flashlight.
Mode Selector (Fig. A, D)
Your tool is equipped with a mode selector
you to select one of three modes. Select the mode based on the
application and control the speed of the tool using the variable
speed trigger switch 1 .
Precision Drive (Fig. D)
In addition to normal impacting modes, this tool features the
Precision Drive mode which enables greater control in lighter
applications to avoid damage to materials or fasteners. It is ideal
for light applications such as cabinet hinge screws or machine
screws. Precision Drive mode will work as a screwdriver in light
applications, before hesitating as the screw head reaches the
work piece, and then (if required) start a slow controlled impact
to ensure the head ends perfectly flush.
nOTE: This mode is for light duty screwdriving applications. If
the tool will not drive a fastener in Precision Mode, please select
mode 2 which will give the additional power required.
Mode 1 Precision Drive
Mode 2 Normal Impacting
Mode 3 High Speed Impacting
Quick-Release Chuck (Fig. A, E, F)

WARNING: Use only impact accessories. Non-impact
accessories may break and cause a hazardous condition.
Inspect accessory prior to use to ensure that it con tains
no cracks.
nOTE: The chuck accepts 6.35 mm hex accessories only.
Place the forward/reverse button
position or remove battery pack before changing accessories.
To install an accessory, fully insert the accessory. The accessory is
locked into place (Fig. E).
To remove an accessory, pull the chuck collar
front of the tool. Remove the accessory (Fig. F).
Usage
Your impact tool generates the following maximum torque:
7 located around the 6.35 mm hex
11 which allows
DCF850
rpm
rpm
rpm
in the lock-off (centre)
2
3 away from the
Cat #
DCF850

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 into the chuck. Keep the tool pointed
straight at the work piece.
2. Press switch to start operation. Release the 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.
- Socket size: Failure to use the correct socket 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

Your D WALT power tool has been designed to operate
e
over a long period of time with a minimum of maintenance.
Continuous satisfactory operation depends upon proper tool
care and regular cleaning.

WARNING: To reduce the risk of serious personal
injury, turn tool off and disconnect battery pack
0–1000
before making any adjustments or removing/
installing attachments or accessories. An accidental
0–2800
start-up can cause injury.
0–3250
The charger and battery pack are not serviceable.
Lubrication
Your power tool requires no additional lubrication.
Cleaning

WARNING: Blow dirt and dust out of the main housing
with dry air as often as dirt is seen collecting in and around
the air vents. Wear approved eye protection and approved
dust mask 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 materials used in these parts.
Use a cloth dampened only with water and mild soap.
English
nm
206.2
11