Starting Operation - Bosch GSN 90-21 RK Manual Original

OBJ_BUCH-1037-005.book Page 14 Monday, November 10, 2014 12:55 PM
14 | English
Declaration of Conformity
We declare under our sole responsibility that the product
described under "Technical data" complies with all applica-
ble provisions of the directive 2006/42/EC including its
amendments and is in conformity with the following stand-
ards: EN 792-13.
Technical file (2006/42/EC) at:
Robert Bosch GmbH, PT/ETM9,
70764 Leinfelden-Echterdingen, GERMANY
Henk Becker Helmut Heinzelmann
Executive Vice President Head of Product Certification
Engineering PT/ETM9
Robert Bosch GmbH, Power Tools Division
70764 Leinfelden-Echterdingen, GERMANY
Leinfelden, 12.11.2014
Assembly
Connecting the Air Supply (see figure A)
Make sure that the pressure of the compressed-air system
is below the maximum permitted rated pressure of the
pneumatic tool. Firstly, set the air pressure to the lower
value of the recommended rated pressure (see "Technical
Data").
When in doubt, check the pressure at the air inlet with a
pressure gauge with the pneumatic tool switched on.
For maximum performance, the values for the supply-air
hose 13 (connection thread, maximum operating pres-
sure, inner hose diameter, maximum hose length; see
"Technical Data") must be observed.
The compressed air supplied should be free of foreign ma-
terial and moisture to protect the tool from damage, con-
tamination, and the formation of rust.
All fittings, connecting lines and hoses must be dimen-
sioned for the pressure and the required air volume.
Avoid restrictions in the air supply, e.g., from pinching,
kinking, or stretching!
Connecting the Air Supply to the Pneumatic Tool
– Empty the magazine 8.
(See "Emptying the Magazine", page 14)
For the following worksteps, a fastener can be dis-
charged when interior parts of the pneumatic tool are
not in the starting position due to repairs, maintenance
or transport.
– Connect the air connector 6 with a supply-air hose 13
equipped with an air-connection coupling 12.
– Check the proper function by placing the outlet 11 or
the rubber workpiece protector 1 of the pneumatic tool
onto a piece of scrap wood or wood material, and dis-
charging once or twice.
Loading the Magazine (see figures B1–B2)
Disconnect the air supply before making
any adjustments, changing accessories,
or placing the pneumatic tool aside. This
safety measure prevents accidental start-
ing of the pneumatic tool.
 Use only original Bosch accessories (see "Technical
Data"). The precision parts of the pneumatic tool such
as the magazine, the outlet and the shot duct are
matched to Bosch staples, nails and brads. Other man-
ufacturers use other steel qualities and sizes.
Using fasteners not permitted, can damage the pneu-
matic tool and cause injuries.
While loading the magazine, hold the pneumatic tool in
such a manner that the outlet 11 is not pointed at your own
body or at other persons.
– Pull back the magazine slider 7 until it engages at the
rear.
Note: The magazine slider must slide back with only low
force (finger-pressure). A tight-running magazine slider
causes the nails to be driven in at an incorrect angle.
– Clean and lubricate the magazine slider 7 as required
and make sure that the magazine 8 is not dirty/soiled.
– Insert a fitting nail strip 14.
1 609 92A 10Z | (10.11.14)
Do not use nail strips with less than 5 nails. Do not insert
more than 2 nail strips. Make sure that the heads of the
nails do not overlap.
GSN 90-34 DK: With this pneumatic tool, a lock function
of the magazine slider prevents the last nails from being
discharged. Approx. 7 nails remain in the magazine.
– Completely pull back the magazine slider 7 once more
to free the lock.
– Carefully guide the magazine slider to the front until it
touches the nail strip.
Make sure that the magazine slider is slid beyond the
head of the last nail.
Note: Do not let the magazine slider snap back without
guiding it. Otherwise, the magazine slider could become
damaged, and there is danger of your fingers being caught
or pinched.
Operation
Actuation systems
The pneumatic tool can be operated with two different ac-
tuations systems:
– Single actuation with safety run
With this actuation system, the discharge lock-off 2
must first be firmly pressed against the workpiece. A
fastener is not discharged until the trigger 10 is pulled.
Afterwards, further discharging procedures can only be
actuated, when the trigger and the discharge lock-off
have first been set back to the starting position.
– Contact actuation
With this actuation system, the trigger 10 must be
pulled first. A fastener is always discharged when the
discharge lock-off 2 is firmly pressed against the work-
piece while the trigger is pressed.
This enables a higher working speed to be achieved.
The actuation system is set via the selector switch 9.

Starting Operation

Disconnect the air supply before making
any adjustments, changing accessories,
or placing the pneumatic tool aside. This
safety measure prevents accidental start-
ing of the pneumatic tool.
Working with Single Actuation (see figure C)
– Press selector switch 9 inward and at the same time piv-
ot it to the bottom position until it engages.
The actuation system "single
actuation" is set.
– Release the selector switch 9 again.
– Firmly position the outlet 11 or the rubber workpiece
protector 1 on the workpiece until discharge lock-off 2
is pressed in completely.
– Afterwards, briefly press trigger 10 and release again.
A nail is discharged.
– Allow the pneumatic tool to bounce back from the work-
piece.
– For another driving procedure, completely lift the pneu-
matic tool from the workpiece and position it firmly at
the next desired location.
Working with Contact Actuation (see figure D)
– Press selector switch 9 inward and at the same time piv-
ot it to the upper position until it engages.
The actuation system
"contact actuation" is
set.
– Release the selector switch 9 again.
– Press and hold the trigger 10.
– Firmly position the outlet 11 or the rubber workpiece
protector 1 on the workpiece until discharge lock-off 2
is pressed in completely.
A nail is discharged.
– Allow the pneumatic tool to bounce back from the work-
piece.
– For another driving procedure, completely lift the pneu-
matic tool from the workpiece and position it firmly at
the next desired location.
– Move the pneumatic tool uniformly over the workpiece
by lifting it off and applying it again.
Each time when applying the pneumatic tool while the
discharge lock-off is pressed in, a nail will be dis-
charged.
– As soon as the desired amount of nails have been driven
in, release trigger 10 again.
Working Advice
Disconnect the air supply before making
any adjustments, changing accessories,
or placing the pneumatic tool aside. This
safety measure prevents accidental start-
ing of the pneumatic tool.
Check the proper function of the safety and actuation de-
vices, and the tight seating of all screws and nuts each time
before using.
Disconnect a defective or not properly operating pneumat-
ic tool immediately from of the air supply and contact an
authorised service agent for Bosch power tools.
Do not perform any incorrect manipulations on the pneu-
matic tool. Do not disassemble or block any components of
the pneumatic tool, such as the discharge lock-off.
Do not carry out "emergency repairs" with unsuitable
means. The pneumatic tool is to be maintained regularly
and properly (see "Maintenance and Cleaning", page 15).
Avoid any weakening and damage whatsoever of the pneu-
matic tool, e.g., through:
– Imprinting or engraving,
– Retrofitting measures not approved by the manufactur-
er,
– Guiding along templates manufactured of hard material,
e.g. steel,
– Dropping on or sliding over the floor,
– Using as a hammer,
– Applying any kind of force.
Make sure to check whatever is below or behind your work-
piece. Do not shoot nails into walls, ceilings or floors, when
persons are behind them. The nails can burst through the
workpiece and injure someone.
Do not shoot a nail onto an already driven-in one. This
could cause the nail to deform, the nails could become
jammed or the pneumatic tool could move uncontrolled.
When the pneumatic tool is used under cold ambient con-
ditions, the first nails will be driven in slower than usual.
Once the pneumatic tool has warmed up during working,
normal operating speed will be regained.
Avoid blank shots in order to reduce the wear of the impact
striker.
For longer work breaks or after finishing work, disconnect
the pneumatic tool from the air supply and empty the mag-
azine.
Emptying the Magazine
– Pull back the magazine slider 7 until it engages at the
rear.
– Remove the nail strips 14.
Discard nail strips with less than 5 nails.
– Completely pull back the magazine slider 7 once more
to free the lock.
– Carefully guide the magazine slider to the front until it
touches the beginning of the magazine.
Note: Do not let the magazine slider snap back without
guiding it. Otherwise, the magazine slider could become
damaged, and there is danger of your fingers being caught
or pinched.
Adjusting the Depth Stop (see figure E)
The driving depth of the nails can be set with thumbwheel
3.
– Empty the magazine 8.
(See "Emptying the Magazine", page 14)
– Nails are driven in too deeply:
To reduce the driving depth, turn thumbwheel 3 in
clockwise direction.
or
Nails are not driven in deep enough:
To increase the driving depth, turn thumbwheel 3 in an-
ticlockwise direction.
Bosch Power Tools