Starting Operation; Working With The Power Tool; Before Cutting - Bosch Professional GAC 250 Original Instructions Manual

The power tool can be directly connected to the socket of a
Bosch all-purpose dust extractor with remote starter. This
dust extractor is started up automatically when the power
tool is switched on.
The dust extractor must be suitable for the material being
worked.
When extracting dry dust or dust that is especially detri-
mental to health or carcinogenic, use a special dust ex-
tractor.
Operation

Starting Operation

Pay attention to the mains voltage! The voltage of the
u
power source must match the voltage specified on the
rating plate of the power tool. Power tools marked
with 230 V can also be operated with 220 V.
Products that are only sold in AUS and NZ: Use a resid-
u
ual current device (RCD) with a nominal residual current
of 30 mA or less.
Switching On and Off
Pull the hand guard/lever for activating the front
brake (4) from position to position
of the front handle (3) (see figure E). If you have not op-
erated the hand guard/lever for activating the front
brake (4), the front brake has not been deactivated be-
fore use and the power tool will not start up.
Remove the chain guard (7).
Hold the power tool as described in the "Working with the
Power Tool" section.
To start the power tool, first press the lock-off button (14),
then press and hold the on/off switch (2).
If the power tool is running, you can release the lock-off func-
tion.
To switch off the power tool, release the on/off switch (2).
Note: For safety reasons, the on/off switch (2) cannot be
locked; it must remain pressed throughout operation.
Note: Do not slow down the power tool by activating the
front brake (4).
Run-Out Brake/Front Brake (see figure E)
The power tool is fitted with two protective devices:
The run-out brake slows down the saw chain after the on/off
switch (2) is released.
The front brake is a protective mechanism that is triggered
via the lever for activating the front brake (4) if the power
tool kicks back or the on/off switch fails. The saw chain stops
immediately.
Perform a function test from time to time. Push the lever for
activating the front brake (4) forwards (position
briefly switch on the power tool. The saw chain must not
start up. To unlock the front brake again, pull the lever for ac-
tivating the front brake (4) back again (position
Bosch Power Tools
Do not carry the power tool by the lever for activating the
front brake.

Working with the Power Tool

Before Cutting

The following checks must be performed before starting op-
eration and regularly during sawing:
– Is the power tool in a safe state?
– Is the saw chain tensioned and sharpened correctly? Dur-
ing sawing, check the chain tension regularly every ten
minutes. Particularly when using new saw chains, in-
creased extension should be expected initially. The state
of the saw chain greatly influences the sawing perform-
ance. Only sharp saw chains protect against overload.
– Is the front brake released and its function ensured?
– Are you wearing the required protective equipment? Use
safety goggles, a dust mask and hearing protection. It is
recommended that you wear additional protective equip-
ment for your head, hands, legs and feet. Wearing suit-
able protective clothing reduces the risk of injury from fly-
ing cut material and the saw chain accidentally coming
into contact with an object.
in the direction
Saw Kickback (see figure E)
A saw kickback is the sudden uncontrolled movement and
kickback of the running power tool, which can occur if the tip
of the chain bar comes into contact with the material to be
sawn or if the chain jams.
If a kickback occurs, the power tool may respond unpredict-
ably and cause severe injuries to the operator or bystanders
in the cutting area.
Particular care must be taken for lateral, bevel and rip cuts
because the stop (10) cannot be applied.
To prevent saw kickbacks:
– Position the power tool so that it is as flat as possible.
– Never work with a loose, extended or heavily worn saw
chain.
– Never saw above shoulder height.
– Never saw using the tip of the chain bar.
– Always hold the power tool firmly with both hands.
– Always use a Bosch saw chain for autoclaved aerated con-
crete (accessory).
– Use the stop (10) as a lever.
– Make sure that the chain tension is correct.
General Behaviour (see figures E–H)
Always hold the power tool firmly with both hands, with your
left hand on the front handle and your right hand on the rear
handle. Always grasp the handles with your thumb and fin-
ger. Always guide the mains cable to the rear and keep it out-
) and
side the area of the saw chain and material to be sawn.
Ensure you always have a secure footing when operating the
power tool.Hold the power tool slightly to the right of your
).
body.
English | 13
1 609 92A 8GB | (03.04.2023)