OBJ_BUCH-1801-002.book Page 16 Monday, November 16, 2015 8:42 AM
Operation
Starting Operation
Observe the mains voltage! The voltage of the
power source must correspond with the data on
the type plate of the machine.
Switching On and Off
To start the machine, press the On/Off switch 4.
To lock the On/Off switch, keep it pressed and ad-
ditionally push the lock-on button 5.
To switch off the machine, release the On/Off
switch 4. When the On/Off switch 4 is locked,
press it first and then release it.
To save energy, only switch the power tool on
when using it.
Preselecting the Orbital Stroke Rate
With the thumbwheel for preselection of the orbital
stroke rate 3, you can preselect the required orbital
stroke rate, even during operation.
1 – 2 Low stroke rate
3 – 4 Medium stroke rate
5 – 6 High stroke rate
The required stroke rate depends on the material
and the working conditions and can be determined
through practical testing.
After longer periods of working at low stroke rate,
allow the machine to cool down by running it for
approx. 3 minutes at maximum stroke rate with no
load.
Sanding Plate Brake
An integrated sanding plate brake reduces the
stroke rate when running at no-load so that scoring
is prevented when placing the machine onto the
workpiece.
If the no-load stroke rate continuously increases
over the course of time, then the sanding plate is
damaged and must be replaced or the sanding
plate brake is worn. A worn sanding plate brake
must be replaced by an authorised after-sales ser-
vice agent for Berner power tools.
Working Advice
Before any work on the machine itself, pull the
mains plug.
Wait until the machine has come to a standstill
before placing it down.
The power tool is not suitable for stationary
operation. For example, it may not be clamped
in a vice or fastened on a workbench.
Sanding Surfaces
Switch the machine on, place it with the complete
sanding surface on the surface to be worked and
move the machine with moderate pressure over the
workpiece.
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The removal capacity and the sanding pattern are
mainly determined by the selection of the sanding
sheet, the preselected orbital stroke rate and the
applied pressure.
Only flawless sanding sheets achieve good sand-
ing capacity and extend the service life of the ma-
chine.
Pay attention to apply uniform sanding pressure;
this increases the working life of the sanding
sheets.
Intensifiying the sanding pressure does not lead to
an increase of the sanding capacity, but to in-
creased wear of the machine and the sanding
sheet.
A sanding sheet that has been used for metal
should not be used for other materials.
Use only original Berner sanding accessories.
Rough Sanding
Attach a sanding sheet with coarse grain.
Apply only light pressure to the machine so that it
runs at a higher stroke rate and high material re-
moval is achieved.
Fine Sanding
Attach a sanding sheet with fine grain.
By lightly varying the application pressure or
changing the orbital stroke rate, the sanding plate
stroke rate can be reduced whereby the orbital ac-
tion is maintained.
With moderate pressure, move the machine in a
circular pattern or alternately in lengthwise and
crosswise directions over the workpiece. Do not tilt
the machine to avoid sanding through the work-
piece (e. g. when sanding veneer).
After finishing the working procedure, switch the
power tool off.
Polishing
For the polishing of weathered paint or buffing out
scratches (e.g., acrylic glass), the machine can be
equipped with appropriate polishing accessories
such as lamb's wool bonnet, polishing felt or
sponge (accessories).
Select a low stroke rate (setting 1 – 2) for polishing
in order to avoid excessive heating of the surface.
Apply the polish onto a somewhat smaller surface
than you intend to polish. Work the polishing agent
in with a suitable polishing tool applying it cross-
wise or with circular motion and moderate pres-
sure.
Do not allow the polishing agent to dry out on the
surface, otherwise the surface can become dam-
aged. Do not subject the surface to be polished to
direct sunlight.
Clean the polishing accessories regularly to ensure
good polishing results. Wash out polishing acces-
sories with a mild detergent and warm water; do
not use paint thinner.
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