Starting Operation; Working Advice - Bosch GWS 12V-76 Professional Manual Original

OBJ_BUCH-2937-001.book Page 18 Thursday, July 21, 2016 1:30 PM
18 | English
– 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
materials to be worked.
 Prevent dust accumulation at the workplace. Dust can
easily ignite.
Operation

Starting Operation

Inserting the battery
Note: Use of batteries not suitable for the machine can lead to
malfunctions of or cause damage to the power tool.
Insert the charged battery 4 into the handle until it can be felt
to engage and faces flush against the handle.
Switching On and Off
To start the power tool, push the On/Off switch 3 forwards.
To lock the On/Off switch 3, press the On/Off switch 3 down
at the front until it latches.
To switch off the power tool, release the On/Off switch 3 or,
if it is locked, briefly push down the back of the On/Off switch
3 and then release it.
To save energy, only switch the power tool on when using it.
 Check grinding tools before using. The grinding tool
must be mounted properly and be able to move freely.
Carry out a test run for at least one minute with no load.
Do not use damaged, out-of-centre or vibrating grind-
ing tools. Damaged grinding tools can burst and cause in-
juries.
Temperature Control/Overload Protection Indicator
The red LED indicator 6 will help you in protecting the battery
against overheating and the motor against overloading.
When the LED indicator 6 continuously lights up red, the
temperature of the battery is too high and the machine
switches off automatically.
– Switch the power tool off.
– Allow the battery to cool down before continuing to work.
The LED indicator 6 flashes red, the power tool is blocked
and switches off automatically.
– Remove the power tool from the workpiece.
The power tool will continue to work as soon as the block-
age is rectified.

Working Advice

 Exercise caution when cutting slots in structural walls;
see Section "Information on Structures".
 When cutting lightweight materials, take into account
the statutory provisions and recommendations of the
material manufacturer.
 Clamp the workpiece if it does not remain stationary
due to its own weight.
 Do not strain the machine so heavily that it comes to a
standstill.
1 609 92A 29F | (21.7.16)
 After heavily straining the power tool, continue to run
it at no-load for several minutes to cool down the acces-
sory.
 Do not touch grinding and cutting discs before they
have cooled down. The discs can become very hot while
working.
 Do not use the power tool with a cut-off stand.
When the power tool is electrostatically charged, the built-in
electronic control switches it off. To restart the power tool,
press the On/Off switch 3 again.
Rough Grinding
 Never use a cutting disc for roughing.
The best roughing results are achieved when setting the ma-
chine at an angle of 30° to 40°. Move the machine back and
forth with moderate pressure. In this manner, the workpiece
will not become too hot, does not discolour and no grooves
are formed.
Cutting Metal
 For cutting with bonded abrasives, always use the pro-
tection guard for cutting 10.
When cutting, work with moderate feed, adapted to the mate-
rial being cut. Do not exert pressure onto the cutting disc, tilt
or oscillate the machine.
Do not reduce the speed of running down cutting discs by ap-
plying sideward pressure.
The machine must always work in an up-grinding motion. Oth-
erwise, the danger exists of it being pushed uncontrolled out
of the cut.
When cutting profiles and square bar, it is best to start at the
smallest cross section.
Cutting Stone
 Provide for sufficient dust extraction when cutting
stone.
 Wear a dust respirator.
 The machine may be used only for dry cutting/grinding.
For cutting stone, it is best to use a diamond cutting disc.
For cutting especially hard material, e. g., concrete with high
pebble content, the diamond cutting disc can overheat and
become damaged as a result. This is clearly indicated by cir-
cular sparking, rotating with the diamond cutting disc.
In this case, interrupt the cutting process and allow the dia-
mond cutting disc to cool by running the machine for a short
time at maximum speed with no load.
Noticeably decreasing work progress and circular sparking
are indications of a diamond cutting disc that has become
dull. Briefly cutting into abrasive material (e. g. lime-sand
brick) can resharpen the disc again.
Information on Structures
Slots in structural walls are subject to the Standard DIN 1053
Part 1, or country-specific regulations.
These regulations are to be observed under all circumstanc-
es. Before beginning work, consult the responsible structural
engineer, architect or the construction supervisor.
Bosch Power Tools