Causes And Operator Prevention Of Kickback - DeWalt D28111 Instruction Manual

• The max. allowable speed of the grinding wheel or cutting
disc must always be equal to or greater than the no-load
speed of the tool specified on the nameplate.
• Do not cut workpieces requiring a maximum depth of cut
exceeding that of the cutting disc.
• Do not use grinding and cutting discs that do not conform
to the dimensions stated in the technical data. Do not use
any spacers to make a disc fit onto the spindle.
• Inspect grinding and cutting discs before each use. Do not
use chipped, cracked or otherwise defective discs.
• If provided, ensure that blotters are used when the disc is
fitted onto the spindle.
• When applying a threaded hole disc, ensure that the thread
is long enough to accept the spindle.
• Ensure that the grinding or cutting disc is mounted
correctly before use.
• Let the tool run at no-load in a safe position for at least 30
seconds. If there is a considerable vibration or if any other defect
occurs, stop the tool and check it to determine the cause.
• Do not operate this tool without the guard in place.
• Check that the workpiece is properly supported.
• Do not operate the tool near flammable liquids, gases or
dust. Sparks or hot chips from cutting or arcing motor brushes
may ignite combustible materials.
• Do not operate the tool while standing in line with the disc.
Keep other persons away from the work area.
• Do not use cutting discs for side grinding.
• Do not operate the spindle lock while the tool is running.
• Beware that after switching off the tool the wheel continues
to rotate for a short period.
• Always store grinding and cutting discs in a dry place.
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.
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