Hilti SCW 18-A, Original Operating Instructions

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4
Kickback causes and related warnings
• kickback is a sudden reaction to a pinched, bound 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 bound 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 and check that saw
teeth are not engaged into the material. If saw blade is binding, 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 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 lower guard for proper closing before each use. Do not operate the saw if lower guard does
not move freely and close instantly. Never clamp or tie the lower guard into the open position. If
saw is accidentally dropped, 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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Lower guard may be retracted manually only for special cuts such as "plunge cuts" and "compound
cuts". Raise lower guard by retracting handle and as soon as blade enters the material, the lower
guard must be released. For all other sawing, the lower guard should operate automatically.
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Always observe that the lower guard is covering the blade before placing saw down on bench or
floor. An unprotected, coasting blade will cause the saw to walk backwards, cutting whatever is in its
path. Be aware of the time it takes for the blade to stop after switch is released.
2.1.3 Additional safety instructions
Personal safety
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Modification of the power tool is not permitted.
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Always hold the machine with both hands on the grips provided. Keep the grips dry, clean and free
from oil and grease.
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Wear ear protectors. Exposure to noise can cause hearing loss.
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Respiratory protection must be worn if the power tool is used without a dust removal system for
work that creates dust.
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Operate the tool only together with the safety devices that belong to it.
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Improve the blood circulation in your fingers by relaxing your hands and exercising your fingers
during breaks between working.
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The power tool is not intended for use by inexperienced persons who have received no special
training.
Printed: 20.10.2015 | Doc-Nr: PUB / 5135507 / 000 / 03