16
| English
1 619 929 J12 | (27.4.11)
Bosch Power Tools
Impact Drilling
Set the selector switch
2
to the “Impact drilling”
symbol.
The selector switch
2
engages noticeably and can also be ac-
tuated with the machine running.
Gear Selection, Mechanical
f
The gear selector 7 can be actuated on machines run-
ning at low speed. However, this should not be done
when the machine is stopped, at full load or running at
maximum speed.
Two speed ranges can be preselected with the gear selector
7
.
Gear I:
Low speed range; for working with large drill-
ing diameter or for driving in screws.
Gear II:
High speed range; for working with small
drilling diameter.
If the gear selector
7
cannot be fully engaged, lightly rotate
the drive spindle with the drill bit by twisting the drill chuck.
Switching On and Off
To
start
the machine, press the On/Off switch
6
and keep it
pressed.
To lock the
pressed
On/Off switch
6
, press the lock-on button
4
.
To
switch off
the machine, release the On/Off switch
6
or
when it is locked with the lock-on button
4
, briefly press the
On/Off switch
6
and then release it.
Safety Clutch
To limit high reaction torque, the power tool is equipped with
a safety clutch (Anti-Rotation).
f
If the tool insert becomes caught or jammed, the drive
to the drill spindle is interrupted. Because of the forces
that occur, always hold the power tool firmly with both
hands and provide for a secure stance.
f
If the power tool jams, switch the machine off and loos-
en the tool insert. When switching the machine on with
the drilling tool jammed, high reaction torques can oc-
cur.
Adjusting the Speed/Impact Frequency
The speed/impact rate of the switched on power tool can be
variably adjusted, depending on how far the On/Off switch
6
is pressed.
Light pressure on the On/Off switch
6
results in low speed/im-
pact rate. Further pressure on the switch increases the
speed/impact rate.
Preselecting the Speed/Impact Frequency
With the thumbwheel for speed preselection
5
, the required
speed/impact frequency can be preselected even during op-
eration.
The required speed/impact frequency depends on the mate-
rial and the working conditions, and can be determined
through practical testing.
Working Advice
f
Before any work on the machine itself, pull the mains
plug.
f
Apply the power tool to the screw/nut only when it is
switched off.
Rotating tool inserts can slip off.
Tips
After longer periods of working at low speed, allow the ma-
chine to cool down by running it for approx. 3 minutes at max-
imum speed with no load.
For drilling in tiles, set the selector switch
2
to the “Drilling”
symbol. Do not switch over to the symbol “Impact Drilling” or
work with impact until after drilling through the tile.
Use carbide tipped drill bits when working in concrete, ma-
sonry and brick wall.
For drilling in metal, use only perfectly sharpened HSS drill
bits (HSS=high-speed steel). The appropriate quality is guar-
anteed by the Bosch accessories program.
Twist drills from 2.5–10 mm can easily be sharpened with
the drill bit sharpener (see accessories).
Maintenance and Service
Maintenance and Cleaning
f
Before any work on the machine itself, pull the mains
plug.
f
For safe and proper working, always keep the machine
and ventilation slots clean.
If the machine should fail despite the care taken in manufac-
turing and testing procedures, repair should be carried out by
an after-sales service centre for Bosch power tools.
In all correspondence and spare parts order, please always in-
clude the 10-digit article number given on the type plate of
the machine.
After-sales Service and Customer Assistance
Our after-sales service responds to your questions concern-
ing maintenance and repair of your product as well as spare
parts. Exploded views and information on spare parts can al-
so be found under:
www.bosch-pt.com
Our customer service representatives can answer your ques-
tions concerning possible applications and adjustment of
products and accessories.
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