Makita 5402NA - Manual (Page 6)

6
11. Causes and Operator Prevention of Kick-
back:
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 procedures or conditions
and can be avoided by taking proper precau-
tions 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 precautions are taken.
When blade is binding, or when interrupt-
ing a cut for any reason, release the trig-
ger and hold the saw motionless in the
material until the blade comes to a com-
plete stop. Never attempt to remove the
saw from the work or pull the saw back-
ward while the blade is in motion or KICK-
BACK 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 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.
Support large panels to minimize 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 as shown in Fig. 1.
To minimize the risk of blade pinching and
kickback. When cutting operation requires
the resting of the saw on the workpiece, the
saw should be rested on the larger portion
and the smaller piece cut off.
Do not use dull or damaged blade.
Unsharpened or improperly set blades pro-
duce narrow kerf causing excessive friction,
blade binding and KICKBACK. Keep blade
sharp and clean. Gum and wood pitch hard-
ened on blades slows saw and increases
potential for kickback. Keep blade clean by
first removing it from tool, then cleaning it
with gum and pitch remover, hot water or ker-
osene. Never use gasoline.
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.
Use extra caution when making a “Pocket
Cut” into existing walls or other blind
areas. The protruding blade may cut objects
that can cause KICKBACK. For pocket cuts,
retract lower guard using Retracting Lever.
ALWAYS hold the tool firmly with both
hands. NEVER place your hand or fingers
behind the saw. If kickback occurs, the saw
Fig. 1 To avoid kickback, do support board or
panel near the cut.
Fig. 2 Do not support board or panel away
from the cut.