Causes And Operator Prevention Of Kickback - DeWalt DC390 Guide D'utilisation

• Check lower guard for proper closing before use. Do not oper-
ate saw if lower guard does not move freely and close instant-
ly. 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.
• Check the operation and condition 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 slug-
gishly due to damaged parts, gummy deposits, or a buildup of
debris.
• Lower guard should be retracted manually only for special
cuts such as "Pocket Cuts" and "Compound Cuts." Raise
lower guard by Retracting Handle. As soon as blade enters
the material, lower guard must be released. For all other saw-
ing, the lower guard should operate automatically.
• 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 what-
ever is in its path. Be aware of the time it takes for the blade to stop
after switch is released.
• NEVER hold piece being cut in your hands or across your leg.
It is important to support the work properly to minimize body expo-
sure, blade binding, or loss of control.
• Hold tool by insulated gripping surfaces when performing an
operation where the cutting tool may contact hidden wiring.
Contact with a "live" wire will make exposed metal parts of the tool
"live" and shock the operator.
• When ripping always use a rip fence or straight edge guide.
This improves the accuracy of cut and reduces the chance for
blade binding.
• Always use blades with correct size and shape (diamond vs.
round) arbor holes. Blades that do not match the mounting hard-
ware of the saw will run eccentrically, causing loss of control.
• Never use damaged or incorrect blade washers or bolts. The
blade washers and bolt were specially designed for your saw, for
optimum performance and safety of operation.
• Avoid cutting nails. Inspect for and remove all nails from lumber
before cutting.

CAUSES AND OPERATOR PREVENTION OF KICKBACK

• 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
operator.
• Kickback is the result of tool misuse and/or incorrect operating pro-
cedures or conditions and can be avoided by taking proper pre-
cautions as given below:
• Maintain a firm grip with both hands on the saw and position
your body and arm to allow you to resist kickback forces.
Kickback forces can be controlled by the operator, if proper pre-
cautions are taken.
• When blade is binding, or when interrupting a cut for any rea-
son, 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 back-
ward while the blade is in motion or kickback may occur.
Investigate and take corrective actions to eliminate the cause of
blade binding.
• When restarting a saw in the workpiece, center the saw blade
in the kerf and check that the 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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