DeWalt DCH172 User Manual

11
ENGLISH
Electronic Overload Protection
If the drill bit becomes jammed, the power to the drill
spindle will be interrupted by the activation of the electronic
overload protection. To reactivate the power to the drive
spindle, the tool's trigger should be released and then
depressed. Due to the resulting forces, always hold the tool
with both hands and take a firmstance.
NOTICE: If drilling thin material, use a wood “back‑up”
block to prevent damage to thematerial.
1. Push the mode selector lever
5
to the drill symbol
16
.
2. Use sharp drill bits only. For Wood, use twist bits,
spade bits, power auger bits or hole saws. For Metal,
use high‑speed steel twist drill bits or hole saws. Use a
cutting lubricant when drilling metals. The exceptions
are cast iron and brass which should be drilled dry. For
MASONRY, such as brick, cement, cinder block, etc., use
carbide‑tipped bits rated for percussiondrilling.
3. Always apply pressure in a straight line with the bit. Use
enough pressure to keep drill biting, but do not push
hard enough to stall the motor or deflect thebit.
4. Hold tool firmly with both hands to control the twisting
action of the drill. If model is not equipped with side
handle, grip drill with one hand on the handle and one
hand on the batterypack.

WARNING: Drill may stall if overloaded causing a
sudden twist. Always expect the stall. Grip the drill
firmly to control the twisting action and avoidinjury.
5. IF DRILL STALLS, it is usually because it is being
overloaded or improperly used. RELEASE TRIGGER
IMMEDIATELY, remove drill bit from work, and determine
cause of stalling. DO NOT depress TRIGGER ON AND OFF
IN AN ATTEMPT TO START A STALLED DRILL — THIS CAN
DAMAGE THEDRILL.
6. To minimize stalling or breaking through the material,
reduce pressure on drill and ease the bit through the last
fractional part of thehole.
7. Keep the motor running when pulling the bit back out of
a drilled hole. This will help preventjamming.
8. With variable speed drills there is no need to center
punch the point to be drilled. Use a slow speed to start
the hole and accelerate by squeezing the trigger harder
when the hole is deep enough to drill without the bit
skippingout.
Drilling in Metal
An SDS plus® to round shank adaptor chuck is required.
Ensure that tool is in drill‑only mode. Start drilling with
slow speed and increase to full power while applying firm
pressure on the tool. A smooth even flow of metal chips
indicates the proper drilling rate. Use a cutting lubricant
when drilling metals. The exceptions are cast iron and brass
which should be drilleddry.
NOTE: Large (5/16" to 1/2" [7.9 mm to 12.7 mm]) holes in
steel can be made easier if a pilot hole (5/32" to 3/16" [4 mm
to 4.8 mm]) is drilledfirst.
Drilling in Wood
An SDS plus® to round shank adaptor chuck is required.
Ensure that tool is in drill‑only mode. Start drilling with
slow speed and increase to full power while applying firm
pressure on the tool. Holes in wood can be made with the
same twist drills used for metal. These bits may overheat
unless pulled out frequently to clear chips from the flutes. For
larger holes, use spade bits, power auger bits, or hole saws.
SDS plus® Chuck (Fig. J)

WARNING: Burn Hazard. ALWAYS wear gloves when
changing bits. Accessible metal parts on the tool and
bits may get extremely hot during operation. Small bits
of broken material may damage barehands.
To insert bit, insert shank of bit about 3/4"(19 mm) into
chuck
14
. Push and rotate bit until it locks in place. The bit
will be securelyheld.
To release bit, pull the sleeve
15
back and remove thebit.
Shocks – Active Vibration Control (Fig. A)
For best vibration control, hold the tool with one hand on the
main handle
6
and the other hand on the side handle
1
.
Apply just enough pressure so the SHOCKS
10
in the rear
handle are halfway depressed. The hammer only needs
enough pressure to engage the internal active vibration
control. Applying too much pressure will not make the tool
drill faster and active vibration control will notengage.
Mode Selector (Fig. I)

CAUTION: Do not change to drill or hammerdrill
mode with a chisel bit in the chuck. Personal injury and
damage to tool mayresult.

CAUTION: Never change the mode while the unit
isrunning.
For drilling (non‑percussion) push the mode selector lever
5
in the up position until the line aligns with the drill bit
symbol
16
. For rotary hammer drilling (with percussion)
push the mode selector lever in the down position until the
line aligns to the drill bit and hammer symbol
17
.
NOTE: The mode selector lever must be in drill or hammer
mode at all times. There are no operable positions
inbetween.
Worklight (Fig. K)

CAUTION: Do not stare into worklight. Serious eye
injury couldresult.
There is a worklight
7
located on the front of the tool. The
worklight is activated when the trigger switch is depressed,
and will automatically turn off 20seconds after the trigger
switch is released. If the trigger switch remains depressed,
the worklight will remainon.
NOTE: The worklight is for lighting the immediate work
surface and is not intended to be used as aflashlight.
Drilling (Fig. I)

WARNING: To reduce the risk of personal injury,
ALWAYS operate the tool with the side handle properly
installed. Failure to do so may result in the side handle
slipping during tool operation and subsequent loss of
control. Hold tool with both hands to maximizecontrol.

DeWalt DCH172 Specifications

General

Brand	DeWalt
Model	DCH172
Category	Rotary Hammer
Language	English