Bosch GBH 11 DE Professional Original Instructions Manual page 13

OBJ_BUCH-58-005.book Page 13 Wednesday, December 5, 2012 4:25 PM
– Turn the bottom part of the auxiliary handle 9 in counter-
clockwise direction and swivel the auxiliary handle 9 to the
desired position. Then retighten the bottom part of the
auxiliary handle 9 by turning in clockwise direction.
Changing the Tool
With the SDS-max tool holder, simpler and easier tool chang-
ing is possible without additional aids.
The dust protection cap 1 largely prevents the penetration of
dust into the tool holder during operation. When inserting the
tool, pay attention that the dust protection cap 1 is not dam-
aged.
 A damaged dust protection cap should be changed im-
mediately. We recommend having this carried out by
an after-sales service.
Inserting (see figure A)
– Clean and lightly grease the shank end of the tool.
– Insert the tool in a twisting manner into the tool holder until
it latches itself.
– Check the latching by pulling the tool.
Removing (see figure B)
– Push back the locking sleeve 2 and remove the tool.
Dust/Chip Extraction
Dusts from materials such as lead-containing coatings, some
wood types, minerals and metal can be harmful to one's
health. Touching or breathing-in the dusts can cause allergic
reactions and/or lead to respiratory infections of the user or
bystanders.
Certain dusts, such as oak or beech dust, are considered as
carcinogenic, especially in connection with wood-treatment
additives (chromate, wood preservative). Materials contain-
ing asbestos may only be worked by specialists.
– Provide for good ventilation of the working place.
– It is recommended to wear a P2 filter-class respirator.
Observe the relevant regulations in your country for the mate-
rials to be worked.
Operation
Starting Operation
 Observe correct mains voltage! The voltage of the pow-
er source must agree with the voltage specified on the
nameplate of the machine. Power tools marked with
230 V can also be operated with 220 V.
Setting the operating mode
The operating mode of the power tool is selected with the
mode selector switch 4.
Note: Change the operating mode only when the machine is
switched off! Otherwise, the machine can be damaged.
– Press and hold the unlocking button 3 and turn the mode
selector switch 4 to the required position.
Bosch Power Tools
Position for hammer drilling
When the drilling tool does not immedi-
ately rotate upon switching on, allow the
machine to run slowly until the drilling
tool rotates.
Vario-Lock position for adjustment of
the chiselling position
Position for chiselling
Switching On and Off
– To start the machine, press the On/Off switch 5 and keep
it pressed.
– To switch off the machine, release the On/Off switch 5.
For low temperatures, the machine reaches the full ham-
mer/impact capacity only after a certain time.
This start-up time can be shortened by striking the inserted
tool insert against the floor one time.
To save energy, only switch the power tool on when using it.
Setting the Speed/Impact Rate
The electronic control enables stepless speed and impact
preselection in accordance with the material to be worked.
The constant electronic control keeps the preselected speed
and impact rate nearly constant between no-load and load
conditions.
The maximum hammering capacity is achieved when the
thumbwheel 7 is set to position "6". For lower speed settings,
the hammering capacity is lower due to technical reasons.
– Select the speed with the thumbwheel 7 according to the
material.
Safety Clutch
 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.
 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.
Working Advice
 Before any work on the machine itself, pull the mains
plug.
Changing the Chiselling Position (Vario-Lock)
The chisel can be locked in 12 positions. In this manner, the
optimum working position can be set for each application.
– Insert the chisel into the tool holder.
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1 609 92A 049 | (5.12.12)