5 - English
ROTARY TOOL SAFETY WARNINGS
KICKBACK AND RELATED WARNINGS
Kickback is a sudden reaction to a pinched or snagged rotating
wheel, sanding band, 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.
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 power tool misuse and/or incorrect
operating procedures or conditions and can be avoided 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.
The operator can control torque reactions or
kickback forces, if proper precautions are taken.
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.
Do not attach a toothed saw blade.
Such blades create
frequent kickback and loss of control.
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).
Feeding 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.
When using rotary files, cut-off wheels, high-speed
cutters or tungsten carbide cutters, always have the
work securely clamped.
These wheels will grab if they
become slightly canted in the groove, and can kickback.
When a cut-off wheel grabs, the wheel itself usually
breaks. When a rotary file, high-speed cutter or tungsten
carbide cutter grabs, it may jump from the groove and
you could lose control of the tool.
SAFETY WARNINGS SPECIFIC FOR
GRINDING AND ABRASIVE CUTTING-OFF
OPERATIONS:
Use only wheel types that are recommended for your
power tool and only for recommended 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.
For threaded abrasive cones and plugs use only
undamaged wheel mandrels with an unrelieved
shoulder flange that are of correct size and length.
Proper mandrels will reduce the possibility of breakage.
Do not “jam” a 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 snagging of the wheel in the
cut and the possibility of kickback or wheel breakage.
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 spinning wheel and the power tool directly
at you.
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 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 eliminate the cause of wheel pinching
or snagging.
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 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.
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.
