Hilti NURON GDG 6-22, Original Operating Instructions, Page: 24 / 468

20 English 2327660
*2327660*
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Do not use accessories that require liquid coolants. Using water or other liquid coolants may result
in electrocution or shock.
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.
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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 kickback forces, if proper precautions are taken.
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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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Do not attach a toothed saw blade. Such blades create frequent kickback and loss of control.
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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.
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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:
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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.
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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.
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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.
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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.
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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.
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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.
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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.
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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 wire brushing operations:
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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.
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Allow brushes to run at operating speed for at least one minute before using them. During this
time no one is to stand in front or in line with the brush. Loose bristles or wires will be discharged
during the run-in time.
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Direct the discharge of the spinning wire brush away from you. Small particles and tiny wire fragments
may be discharged at high velocity during the use of these brushes and may become imbedded in your
skin.