1 619 929 E39.book Seite 3 Freitag, 10. Februar 2006 7:57 07
Changing the Impact Rate
With the On/Off switch 5, the impact frequency
can be changed between low and high impact.
Applying slight pressure on the On /Off switch 5
leads to low impact frequency. With increasing
pressure, the impact frequency increases.
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.
Slide the chisel adjusting ring 3 forward and hold
firmly. Then turn the chisel with the chisel adjust-
ing ring 3 until the desired position is reached.
Release the chisel adjusting ring 3 and turn the
chisel until it locks into place.
Sharpening Chisels
Good results are only achieved with sharp chis-
els, therefore sharpen the chiselling tools in good
time. This prolongs the service life of the tools
and ensures good working performance.
Re-sharpening the Chiselling Tools
Sharpen chiselling tools using grinding wheels
(e. g. ceramic bonded corundum wheel) with a
steady supply of water. Reference values are
shown in Fig. C. Take care that no annealing col-
oration appears on the cutting edges, otherwise
the hardness of the chiselling tools will be im-
paired.
Forging and Hardening
Forging:
Heat the chisel to between 850
and 1050 °C (bright red to yellow)
and forge.
Hardening:
Heat the chisel to 900 °C (bright
red) and quench in oil, then an-
neal in an oven for approx. one
hour at 320 °C (annealing col-
our = light blue).
10 • 1 619 929 E39 • TMS • 06.02.06
All manuals and user guides at all-guides.com
Maintenance and Cleaning
Changing the Dust Protection Cap
A damaged dust protection cap should be
changed immediately. We recommend having
this carried out by an after-sales service.
Lubrication
The machine is oil-lubricated. An oil change is
only required during maintenance or repair
through an authorized after-sales service agent
for Bosch power tools. It is imperative to use the
designated Bosch oil.
If the machine should fail despite the care taken
in manufacturing and testing procedures, repair
should be carried out by an authorized after-sales
service agent for Bosch power tools.
In all correspondence and spare parts orders,
please always include the 10-digit article number
given on the nameplate of the machine.
WARNING! Important instructions for con-
necting a new 3-pin plug to the 2-wire cable.
The wires in the cable are coloured according to
the following code:
Do not connect the blue or brown wire to the
earth terminal of the plug.
Important: If for any reason the moulded plug is
removed from the cable of this machine, it must
be disposed of safely.
English - 3
Before any work on the machine itself, pull the
mains plug.
For safe and proper working, always keep the
machine and its ventilation slots clean.
Keep the tool holder clean at all times.
strain relief
live = brown
neutral = blue
To be fitted
by qualified
professional only