Bosch 11250VSRD Operating Instructions Manual page 12

DRILL/HAMMER DRILL SELECTION DiAL
The selector dial allows the tool to be set for
various drilling/hammer drilling applications.
Depress release button and turn selector dial
right or left depending on the below
applications.
Do not operate the
selection dial until the tool
come to a complete stop. Shifting during
rotation of the chuck can cause damage to
the tool.
Do not use demolition or chipping bits such
as bull points, chisels, spades, gouges, etc.
Drill only action: For drilling in
woods, metals, plastics or
other non concrete materials.
Drill with hammer action: For
drilling in concrete, asphalt,
tile or other similar hard
materials.
Following a few simple tips will reduce wear
on the tool and the chance of injury to the
operator.
NOTE: The high efficiency available from
the rotary hammers can only be obtained if
sharp and undamaged accessories are used.
The "cost" to maintain sharp and undamaged
accessories is more than offset by the "time
saved" in operating the tool with sharp
accessories.
All hammers require a short period of time to
warm up. Depending on the room
temperature, this time may vary from
approximately 15 seconds (90°F) to 2
minutes (322). A new hammer requires a
break-in period before full performance is
realized. This period may require up to 5
hours of operation.
Carbide tipped bits: Used for drilling stone,
concrete, cement, brick, cinder block and
other unusually hard non-metals. The Rotary
Hammer is designed for "SDS" Carbide
Tipped Bits up to 3/4 inch diameter.
Recall these instructions for safe operation:
1. Some materials require slow drilling
speeds; whereas, others require higher speed
to produce the best results.
2. All work must be supported or secured
before drilling and steady, even pressure
applied in line with the drill bit.
3. As the drill bit cuts through the opposite
side, reduce the pressure and continue
running the drill as the bit is withdrawn.
Materials such as glass, porcelain, ceramics,
tiles, plastics, etc., should be drilled at low
speeds with specially designed drill bits and
lubricants.
DRiLLiNG WOOD OR PLASTIC
Do not drill into wood with
dust extraction system
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.
DRILLING METAL
Do not drill into metal with
the dust extraction system
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.
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