Hilti NURON SC 4WL-22, Original Operating Instructions

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*2276127*
2276127 English 21
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Adjust the cutting depth to the thickness of the workpiece. Less than a full tooth of the blade teeth
should be visible below the workpiece.
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Never hold the workpiece in your hands or across your leg while cutting. Secure the workpiece
to a stable platform. It is important to support the work properly to minimise body exposure, blade
binding, or loss of control.
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Hold the power tool by insulated gripping surfaces, when performing an operation where the
cutting tool may contact hidden wiring. Contact with a "live" wire will also make exposed metal parts
of the power tool "live" and could give the operator an electric shock.
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When ripping, always use a rip fence or straight edge guide. This improves the accuracy of cut and
reduces the chance of blade binding.
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Always use blades with correct size and shape (diamond versus round) of arbour holes. Blades
that do not match the mounting hardware of the saw will run off-centre, causing loss of control.
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Never use damaged or incorrect blade washers or bolt. The blade washers and bolt were specially
designed for your saw, for optimum performance and safety of operation.
Kickback causes and related warnings
• kickback is a sudden reaction to a pinched, jammed or misaligned saw blade, causing an uncontrolled
saw to lift up and out of the workpiece toward the operator;
• when the blade is pinched or jammed tightly by the kerf closing down, the blade stalls and the motor
reaction drives the unit rapidly back toward the operator;
• if the blade becomes twisted or misaligned in the cut, the teeth at the back edge of the blade can dig
into the top surface of the wood causing the blade to climb out of the kerf and jump back toward the
operator.
Kickback is the result of saw 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 with both hands on the saw and position your arms to resist kickback forces.
Position your body to either side of the blade, but not in line with the blade. Kickback could cause
the saw to jump backwards, but kickback forces can be controlled by the operator, if proper precautions
are taken.
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When blade is binding, or when interrupting a cut for any reason, release the trigger and hold the
saw motionless in the material until the blade comes to a complete stop. Never attempt to remove
the saw from the work or pull the saw backward while the blade is in motion or kickback may
occur. Investigate and take corrective actions to eliminate the cause of blade binding.
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When restarting a saw in the workpiece, centre the saw blade in the kerf so that the saw teeth are
not engaged into the material. If a saw blade binds, it may walk up or kickback from the workpiece as
the saw is restarted.
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Support large panels to minimise the risk of blade pinching and kickback. Large panels tend to sag
under their own weight. Supports must be placed under the panel on both sides, near the line of cut and
near the edge of the panel.
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Do not use dull or damaged blades. Unsharpened or improperly set blades produce narrow kerf
causing excessive friction, blade binding and kickback.
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Blade depth and bevel adjusting locking levers must be tight and secure before making the cut. If
blade adjustment shifts while cutting, it may cause binding and kickback.
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Use extra caution when sawing into existing walls or other blind areas. The protruding blade may
cut objects that can cause kickback.
Lower guard function
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Check the lower guard for proper closing before each use. Do not operate the saw if the lower
guard does not move freely and close instantly. Never clamp or tie the lower guard into the open
position. If the saw is accidentally dropped, the lower guard may be bent. Raise the lower guard with
the retracting handle and make sure it moves freely and does not touch the blade or any other part, in all
angles and depths of cut.
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Check the operation of the lower guard spring. If the guard and the spring are not operating
properly, they must be serviced before use. Lower guard may operate sluggishly due to damaged
parts, gummy deposits, or a build-up of debris.
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The lower guard may be retracted manually only for special cuts such as "plunge cuts" and
"compound cuts". Raise the lower guard by the retracting handle and as soon as the blade enters
the material, the lower guard must be released. For all other sawing, the lower guard should operate
automatically.