Bosch GWS Professional 20-230 JH Manual Original página 16

OBJ_BUCH-1686-003.book Page 17 Wednesday, April 23, 2014 3:36 PM
 Do not operate the power tool near flammable materi-
als. Sparks could ignite these materials.
 Do not use accessories that require liquid coolants. Us-
ing water or other liquid coolants may result in electrocu-
tion or shock.
Kickback and related warnings
 Kickback is a sudden reaction to a pinched or snagged ro-
tating wheel, backing pad, brush or any other accessory.
Pinching or snagging causes rapid stalling of the rotating
accessory which in turn causes the uncontrolled power
tool to be forced in the direction opposite of the accesso-
ry's rotation at the point of the binding.
For example, if an abrasive wheel is snagged or pinched by
the workpiece, the edge of the wheel that is entering into
the pinch point can dig into the surface of the material
causing the wheel to climb out or kick out. The wheel may
either jump toward or away from the operator, depending
on direction of the wheel's movement at the point of pinch-
ing. Abrasive wheels may also break under these condi-
tions.
Kickback is the result of power tool misuse and/or incor-
rect operating procedures or conditions and can be avoid-
ed by taking proper precautions as given below.
 Maintain a firm grip on the power tool and position your
body and arm to allow you to resist kickback forces. Al-
ways use auxiliary handle, if provided, for maximum
control over kickback or torque reaction during
start-up. The operator can control torque reactions or
kickback forces, if proper precautions are taken.
 Never place your hand near the rotating accessory.
Accessory may kickback over your hand.
 Do not position your body in the area where power tool
will move if kickback occurs. Kickback will propel the
tool in direction opposite to the wheel's movement at the
point of snagging.
 Use special care when working corners, sharp edges,
etc. Avoid bouncing and snagging the accessory. Cor-
ners, sharp edges or bouncing have a tendency to snag the
rotating accessory and cause loss of control or kickback.
 Do not attach a saw chain woodcarving blade or
toothed saw blade. Such blades create frequent kickback
and loss of control.
Safety warnings specific for Grinding and Abrasive
Cutting-Off operations
 Use only wheel types that are recommended for your
power tool and the specific guard designed for the se-
lected wheel. Wheels for which the power tool was not de-
signed cannot be adequately guarded and are unsafe.
 The grinding surface of the centre depressed wheels
must be mounted below the plane of the guard lip. An
improperly mounted wheel that projects through the plane
of the guard lip cannot be adequately protected.
 The guard must be securely attached to the power tool
and positioned for maximum safety, so the least
amount of wheel is exposed towards the operator.
Bosch Power Tools
The guard helps to protect operator from broken wheel
fragments, accidental contact with wheel and sparks that
could ignite clothing.
 Wheels must be used only for recommended applica-
tions. For example: do not grind with the side of the
cut-off wheel. Abrasive cut-off wheels are intended for
peripheral grinding; side forces applied to these wheels
may cause them to shatter.
 Always use undamaged wheel flanges that are of cor-
rect size and shape for your selected wheel. Proper
wheel flanges support the wheel thus reducing the possi-
bility of wheel breakage. Flanges for cut-off wheels may be
different from grinding wheel flanges.
 Do not use worn down reinforced wheels from larger
power tools. Wheels intended for larger power tools are
not suitable for the higher speed of a smaller tool and may
burst.
Additional safety warnings specific for abrasive cutting
off operations
 Do not "jam" the cut-off wheel or apply excessive pres-
sure. Do not attempt to make an excessive depth of cut.
Overstressing the wheel increases the loading and suscep-
tibility to twisting or binding of the wheel in the cut and the
possibility of kickback or wheel breakage.
 Do not position your body in line with and behind the
rotating wheel. When the wheel, at the point of operation,
is moving away from your body, the possible kickback may
propel the spinning wheel and the power tool directly at
you.
 When wheel is binding or when interrupting a cut for
any reason, switch off the power tool and hold the pow-
er tool motionless until the wheel comes to a complete
stop. Never attempt to remove the cut-off wheel from
the cut while the wheel is in motion otherwise kickback
may occur. Investigate and take corrective action to elimi-
nate the cause of wheel binding.
 Do not restart the cutting operation in the workpiece.
Let the wheel reach full speed and carefully re-enter
the cut. The wheel may bind, walk up or kickback if the
power tool is restarted in the workpiece.
 Support panels or any oversized workpiece to minimize
the risk of wheel pinching and kickback. Large work-
pieces tend to sag under their own weight. Supports must
be placed under the workpiece near the line of cut and near
the edge of the workpiece on both sides of the wheel.
 Use extra caution when making a "pocket cut" into ex-
isting walls or other blind areas. The protruding wheel
may cut gas or water pipes, electrical wiring or objects that
can cause kickback.
Safety warnings specific for sanding operations
 Do not use excessively oversized sanding disc paper.
Follow manufacturers recommendations, when select-
ing sanding paper. Larger sanding paper extending be-
yond the sanding pad presents a laceration hazard and
may cause snagging, tearing of the disc, or kickback.
English | 17
1 609 92A 0MJ | (23.4.14)