DeWalt DCD791B, Instruction Manual

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.

Screwdriving (Fig. 10)

 1. Select the desired speed/torque range using the gear shifter to 

match the speed and torque to the planned operation.

  2. Turn the torque adjustment collar (C) to the desired position. 
   

NOTE: 

Use the lowest torque setting required to seat the fastener 

at the desired depth. The lower the number, the lower the torque 

output.

  3. Insert the desired fastener accessory into the chuck as you would 

any drill bit.

 4. Make some practice runs in scrap or on unseen areas of the 

workpiece to determine the proper position of the torque 

adjustment collar. 

  5. Always start with lower torque settings, then advance to higher 

torque settings to avoid damage to the workpiece or fastener.

FIG. 9

HAMMERDRILLING

FIG. 11

SCREWDRIVING

FIG. 10

DRILLING

C

C

Hammerdrilling (Fig. 11)

  1. Select the desired speed/torque range using the gear shifter to 

match the speed and torque to the planned operation. Turn the 

collar (C) to the hammerdrill symbol.

 IMPORTANT:

 Use carbide-tipped or masonry bits rated for 

percussion drilling only.

  2. Drill with just enough force on the hammer to keep it from bouncing 

excessively or "rising" off the bit. Too much force will cause slower 

drilling speeds, overheating, and a lower drilling rate.

  3. Drill straight, keeping the bit at a right angle to the work. Do not 

exert side pressure on the bit when drillling as this will cause 

clogging of the bit flutes and a slower drilling speed.

  4. When drilling deep holes, if the hammer speed starts to drop off, 

pull the bit partially out of the hole with tool still running to help 

clear debris from the hole.

NOTE:

 A smooth, even flow of dust from the hole indicates proper 

drilling rate.

English

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