Causes And Operator Prevention Of Kickback; Safety Warnings Specifi C For Grinding And Abrasive Cutting-Off Operations; Additional Safety Warnings Specifi C For Abrasive Cutting-Off Operations - DeWalt DWE4557 Instruction Manual

Causes and Operator Prevention
of Kickback
Kickback is a sudden reaction to a pinched or snagged rotating
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 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
movement at the point of pinching. Abrasive wheels may also
break under these conditions.
Kickback is the result of 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 reaction or kickback 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 Specifi c 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 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 operator from broken wheel fragments and
accidental contact with wheel.
c) 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.
d) 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.
e) 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 Specifi c 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 possibility of kickback or wheel breakage.
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