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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 power tool misuse and/
or incorrect operating procedures or conditions
and can be avoided by taking proper precau-
tions as given below.
a) Maintain a fi rm grip on the power tool and
position your body and arm to allow you to re-
sist kickback forces. The operator can control
kickback forces, if proper precautions are taken.
b) Use special care when working corners,
sharp edges etc. Avoid bouncing and snag-
ging the accessory. Corners, sharp edges or
bouncing have a tendency to snag the rotating
accessory and cause loss of control or kickback.
c) Do not attach a toothed saw blade. Such
blades create frequent kickback and loss of
control.
d) Always feed the bit into the material in
the same direction as the cutting edge is
exiting from the material (which is the same
direction as the chips are thrown). Fee-
ding the tool in the wrong direction causes the
cutting edge of the bit to climb out of the work
and pull the tool in the direction of this feed.
e) When using rotary fi les, cut-off wheels,
high-speed cutters or tungsten carbide cut-
ters, always have the work securely clamped.
These wheels will grab if they become slightly can-
ted in the groove, and can kickback. When a cut-off
wheel grabs, the wheel itself usually breaks. When
a rotary fi le, high-speed cutter or tungsten carbide
cutter grabs, it may jump from the groove and you
could lose control of the tool.
Safety warnings specifi c for grinding and
abrasive cutting-off operations:
a) Use only wheel types that are recommen-
ded for your power tool and only for recom-
mended applications. For example: do not
grind with the side of a cut-off wheel. Abrasive
cut-off wheels are intended for peripheral grinding,
side forces applied to these wheels may cause
them to shatter.
b) For threaded abrasive cones and plugs
use only undamaged wheel mandrels with an
unrelieved shoulder fl ange that are of correct
size and length. Proper mandrels will reduce the
possibility of breakage.
c) Do not “jam” a cut-off wheel or apply ex-
cessive pressure. Do not attempt to make an
excessive depth of cut. Overstressing the wheel
increases the loading and susceptibility to twis-
ting or snagging of the wheel in the cut and the
possibility of kickback or wheel breakage.
d) Do not position your hand in line with and
behind the rotating wheel. When the wheel, at
the point of operation, is moving away from your
hand, the possible kickback may propel the spin-
ning wheel and the power tool directly at you.
e) When wheel is pinched, snagged 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 com-
plete 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 pinching or snagging.
f) 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.
g) 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 un-
der the workpiece near the line of cut and near
the edge of the workpiece on both sides of the
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