Operating Tips; Drilling Metal - Bosch HD19-2D Operating/Safety Instructions Manual

BM 2609932666 02-12:BM 2609932666 02-12 2/14/12 8:35 AM Page 12
GEAR SELECTION DIAL
Gear selection: The proper gear selection is
directly related to the speed and torque
required for various jobs. The following should
be adhered to when selecting the proper gear:
Speed 1 = low speed with high
torque
CHUCK KEY & STORAGE AREA
Your tool is equipped with a chuck key that is
conveniently located on the cord protector
You will extend the life of your bits and do
neater work if you always put the bit in
contact with the work before pulling the
trigger. During the operation, hold the tool
firmly and exert light, steady pressure. Too
much pressure at low speed will stall the tool.
Too little pressure will keep the bit from
cutting and cause excess friction by sliding
over the surface. This can be damaging to
both tool and bit.
DRILLING WITH VARIABLE SPEED
The trigger controlled variable speed feature
will eliminate the need for center punches in
hard materials. The variable speed trigger
allows you to slowly increase RPM. By using
a slow starting speed, you are able to keep
the bit from "wandering". You can increase
the speed as the bit "bites" into the work by
squeezing the trigger.
DRILL BITS
Always inspect drill bits for excessive wear. Use
only bits that are sharp and in good condition.
TWIST BITS: Available with straight and
reduced shanks for wood and light duty metal
drilling. High speed bits cut faster and last
longer on hard materials.
CARBIDE TIPPED BITS: Used for drilling
stone, concrete, plaster, cement and other
unusually hard nonmetals. Use continuous
heavy feed pressure when employing carbide
tip bits.
DRILLING WOOD OR PLASTIC
Do not drill into wood with
CAUTION
dust extraction system
Changing gears: Change gear position only
with the motor at a complete standstill. To
change gears rotate the gear selection dial. If
you have difficulties changing from one gear to
the other, turn the chuck by hand until the
gears engage (Fig. 1).
where it is always handy and unlikely to get lost
or misplaced.

Operating Tips

mounted. Wood chips are typically too large
and will clog the dust channel.
If backing block is not used, ease up on the
pressure just before the bit breaks through
the wood to avoid splintering. Complete the
hole from the opposite side immediately after
the point breaks through. If bit binds, reverse
the drilling operation to help remove the bit
from the work.
WARNING
mounted. Hot metal chips can self-ignite or
ignite parts of the dust extraction system.
Make a center punch in the material for
easier starting. Use enough pressure to keep
the bit cutting. If the bit is allowed to merely
spin in the hole, it will become dull within a
short time. When drilling a larger hole, it is
faster and easier on your power pack to first
make a smaller hole and enlarge it to the
required size. Lubricate the tip of the bit
occasionally with CUTTING OIL for easier
metal drilling. If bit binds, reverse the drilling
to help remove the bit from the work.
Use carbide-tipped masonry bit for cinder
block, mortar, common brick, soft stone and
other materials. The amount of pressure to be
used is dependent upon the type of material
being drilled. Soft materials require less
pressure while the hard materials need more
pressure to prevent the drill bit from spinning.
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Speed 2 = high speed with low
torque

DRILLING METAL

Do not drill into metal with
the dust extraction system
DRILLING MASONRY