Makita GA4030 Instruction Manual page 7

Kickback and Related Warnings
Kickback is a sudden reaction to a pinched or snagged
rotating wheel, backing pad, brush or any other acces-
sory. Pinching or snagging causes rapid stalling of the
rotating accessory which in turn causes the uncon-
trolled power tool to be forced in the direction opposite
of the accessory'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 move-
ment at the point of pinching. Abrasive wheels may also
break under these conditions.
Kickback is the result of power tool misuse and/or
incorrect operating procedures or conditions and can be
avoided by taking proper precautions as given below.
a) Maintain a firm grip on the power tool and
position your body and arm to allow you to
resist kickback forces. Always use auxiliary
handle, if provided, for maximum control over
kickback or torque reaction during start-up.
The operator can control torque reactions or kick-
back forces, if proper precautions are taken.
b) Never place your hand near the rotating
accessory. Accessory may kickback over your
hand.
c) 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.
d) Use special care when working corners,
sharp edges etc. Avoid bouncing and snagging
the accessory. Corners, sharp edges or bouncing
have a tendency to snag the rotating accessory
and cause loss of control or kickback.
e) 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:
a) Use only wheel types that are recommended
for your power tool and the specific guard
designed for the selected wheel. Wheels for
which the power tool was not designed cannot be
adequately guarded and are unsafe.
b) The grinding surface of 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.
c) 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. The guard helps to protect
the operator from broken wheel fragments, acci-
dental contact with wheel and sparks that could
ignite clothing.
d) Wheels must be used only for recommended
applications. For example: do not grind with
the side of cut-off wheel. Abrasive cut-off wheels
are intended for peripheral grinding, side forces
applied to these wheels may cause them to
shatter.
e) Always use undamaged wheel flanges that
are of correct size and shape for your selected
wheel. Proper wheel flanges support the wheel
thus reducing the possibility of wheel breakage.
Flanges for cut-off wheels may be different from
grinding wheel flanges.
f) Do not use worn down wheels from larger
power tools. Wheel intended for larger power tool
is not suitable for the higher speed of a smaller
tool and may burst.
Additional Safety Warnings Specific for Abrasive
Cutting-Off Operations:
a) Do not "jam" the cut-off wheel or apply
excessive pressure. Do not attempt to make an
excessive depth of cut. Overstressing the wheel
increases the loading and susceptibility to twisting
or binding of the wheel in the cut and the possibil-
ity of kickback or wheel breakage.
b) 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 spin-
ning wheel and the power tool directly at you.
c) When wheel is binding or when interrupting
a cut for any reason, switch off the power
tool and hold the power 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 correc-
tive action to eliminate the cause of wheel binding.
d) 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.
e) Support panels or any oversized workpiece
to minimize the risk of wheel pinching and
kickback. Large workpieces 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.
f) Use extra caution when making a "pocket
cut" into existing 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:
a) Do not use excessively oversized sanding
disc paper. Follow manufacturers recommen-
dations, when selecting sanding paper. Larger
sanding paper extending beyond the sanding
pad presents a laceration hazard and may cause
snagging, tearing of the disc or kickback.
Safety Warnings Specific for Wire Brushing
Operations:
a) Be aware that wire bristles are thrown by
the brush even during ordinary operation. Do
not overstress the wires by applying excessive
load to the brush. The wire bristles can easily
penetrate light clothing and/or skin.
b) If the use of a guard is recommended for
wire brushing, do not allow interference of the
wire wheel or brush with the guard. Wire wheel
or brush may expand in diameter due to work load
and centrifugal forces.
7 ENGLISH