
6
After using the chuck key, be sure to return to the
original position.
For Model HP2071, HP2071F
Fig.9
Hold the ring and turn the sleeve counterclockwise to
open the chuck jaws. Place the bit in the chuck as far as
it will go. Hold the ring firmly and turn the sleeve
clockwise to tighten the chuck.
To remove the bit, hold the ring and turn the sleeve
counterclockwise.
NOTE:
• If the keyless drill chuck cannot be loosened
because of a drill bit being caught inside the jaws
of the chuck, loosen the drill chuck as follows.
Fig.10
1. Hold the sleeve of the drill chuck firmly with water
pump pliers or the like (Note: Do not hold the
retaining ring portion.)
2.
Place the wrench 19, adjustable wrench or one of
other appropriate wrenches on the hexagonal nut at
the front of the drill chuck. Turn the wrench clockwise
as shown in the figure to loosen the drill chuck.
Depth gauge
Fig.11
The depth gauge is convenient for drilling holes of
uniform depth. Loosen the side grip and insert the depth
gauge into the hole in the side grip. Adjust the depth
gauge to the desired depth and tighten the side grip.
NOTE:
• The depth gauge cannot be used at the position
where the depth gauge strikes against the tool
body.
OPERATION
Hammer drilling operation
CAUTION:
• There is a tremendous and sudden twisting force
exerted on the tool/bit at the time of hole break-
through, when the hole becomes clogged with
chips and particles, or when striking reinforcing
rods embedded in the concrete. Always use the
side grip (auxiliary handle) and firmly hold the tool
by both side grip and switch handle during
operations. Failure to do so may result in the loss
of control of the tool and potentially severe injury.
When drilling in concrete, granite, tile, etc., move the
action mode changing lever to the position of symbol
to use "rotation with hammering" action.
Be sure to use a tungsten-carbide tipped bit.
Position the bit at the desired location for the hole, then
pull the switch trigger. Do not force the tool. Light
pressure gives best results. Keep the tool in position
and prevent it from slipping away from the hole.
Do not apply more pressure when the hole becomes
clogged with chips or particles. Instead, run the tool at
an idle, then remove the bit partially from the hole. By
repeating this several times, the hole will be cleaned out
and normal drilling may be resumed.
Blow-out bulb (optional accessory)
Fig.12
After drilling the hole, use the blow-out bulb to clean the
dust out of the hole.
Drilling operation
When drilling in wood, metal or plastic materials, move
the action mode changing lever to the position
of symbol to use "rotation only" action.
Drilling in wood
When drilling in wood, the best results are obtained with
wood drills equipped with a guide screw. The guide
screw makes drilling easier by pulling the bit into the
workpiece.
Drilling in metal
To prevent the bit from slipping when starting a hole,
make an indentation with a center-punch and hammer
at the point to be drilled. Place the point of the bit in the
indentation and start drilling.
Use a cutting lubricant when drilling metals. The
exceptions are iron and brass which should be drilled
dry.
CAUTION:
• Pressing excessively on the tool will not speed up
the drilling. In fact, this excessive pressure will
only serve to damage the tip of your bit, decrease
the tool performance and shorten the service life
of the tool.
• There is a tremendous force exerted on the tool/bit
at the time of hole break through. Hold the tool
firmly and exert care when the bit begins to break
through the workpiece.
• A stuck bit can be removed simply by setting the
reversing switch to reverse rotation in order to
back out. However, the tool may back out abruptly
if you do not hold it firmly.
• Always secure small workpieces in a vise or
similar hold-down device.