Bosch GNA 16 (SDS) Professional - Manual (Page 10)

10 | English
1 619 929 J61 | (25.7.11) Bosch Power Tools
Changing the Cutting Direction
For changing the cutting direction, the die holder 4 can be
turned to three positions, each offset by 90°. Cutting toward
the rear (toward the housing of the machine) is not possible.
For turning the die holder 4 loosen the screw 2 until you can
turn the die holder. Turn it 90 ° to the right or the left in rela-
tion to the longitudinal axle of the power tool.
Make sure that the screw 2 engages into the borehole of the
die holder 4. Tighten the screw 2.
Working Advice
f Before any work on the machine itself, pull the mains
plug.
f The power tool is not suitable for stationary operation.
For example, it may not be clamped in a vice or fastened on
a workbench.
f Wear protective gloves while working and pay particu-
lar attention to the mains cable. Sharp burrs develop at
the cut steel sheet and can cause injuries to the operator or
damage the mains cable.
f Exercise caution when handling the cutting chips. The
chips have sharp tips that can cause injuries.
Apply the machine to the workpiece only when switched on.
Always hold the machine vertical to the surface of the steel
sheet and do not tilt it.
The cut takes place during the downward motion of the
punch. Guide the machine evenly and with moderate feed in
the cutting direction. A high feed rate significantly reduces
the service life of the cutting tools and can damage the ma-
chine.
The machine operates more quietly when it is raised slightly
during cutting. If the punch should become wedged during
cutting, switch the machine off, relubricate the punch and re-
lease the tension of the steel sheet. Do not exert force, other-
wise the punch and the die will become damaged.
Maximum Steel Sheet Cutting Capacity
The maximum steel sheet cutting capacity d
max
depends on
the strength properties of the material to be cut.
The machine allows for straight and deformation-free cutting
of metal sheets to the following thicknesses:
Lubricating/Cooling the Punch
To extend the service life of the punch 3, a lubricating agent
with good cooling properties (e.g. cutting oil) should be used.
Apply a trail of lubricant beads onto the top side of the metal
sheet alongside the intended cutting line. For long periods of
continual use or for work with high frictional wear (e.g. when
cutting aluminium), the cutting head should be immersed into
a container with lubricant in regular intervals.
Cutting along a Cutting Mark or with a Guide
Straight cuts are carried out easier when the machine is guid-
ed alongside a rule.
Contours can be cut by guiding the machine along a template.
For inside cuts, pre-drilling a hole with a diameter of 21 mm is
necessary.
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.
Clean and lubricate the punch 3 and die 5 every 3 operating
hours.
Change the punch and die in good time when worn. Only
sharp tools produce a good cutting quality and make the ma-
chine last longer.
The punch 3 and the die 5 may not be reground.
Changing the Die
Unscrew the knurled screw 7 of the die holder 4. Take out the
die 5.
Il necessary, clean the die holder 4.
Put a new, well greased die 5 into the die holder. Pay attention
to the alignment of the flat side.
Tighten the knurled screw 7 again, the rubber ring placed on-
to it 6. Tighten the screw against the resistance of the rubber
ring.
Changing the Punch
Loosen the screw 2 and pull the die holder und 4 completely
out of the housing.
Push the punch 3 laterally out of the slot in the die holder 4
and pull it down and out.
Place a new, well greased punch 3 into the slot in the die hold-
er 4 and align it centrally.
Push the die holder 4 with caution over the punch 3 back into
the housing. Turn the die holder into one of the three possible
positions (see “Changing the Cutting Direction”, page 10).
Tighten the screw 2.
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
Material Max. strength property
[N/mm
2 ]
d
max
[mm]
Steel 400 1.6
600 1.0
800 0.7
Aluminium 200 2.0
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