Causes And Operator Prevention Of Kickback - Porter Cable PC186CS Manuel D'instructions

90550103 PCL186 Circular Saw
e. Hold power tool by insulated gripping surfaces when performing an operation
where the cutting tool may contact hidden wiring or its own cord. Contact with
a "live" wire will also make exposed metal parts of the power tool "live" and shock
the operator.
f. When ripping always use a rip fence or straight edge guide. This improves the
accuracy of cut and reduces the chance of blade binding.
g. Always use blades with correct size and shape (diamond versus round) of
arbor holes. Blades that do not match the mounting hardware of the saw will run
eccentrically, causing loss of control.
h. 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.

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 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:
a. 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.
b. 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.
c. 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.
d. 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.
e. Do not use dull or damaged blades. Unsharpened or improperly set blades
produce narrow kerf causing excessive friction, blade binding and kickback.
f. 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.
g. Use extra caution when making a "plunge cut" into existing walls or other
blind areas. The protruding blade may cut objects that can cause kickback.
LOWER GUARD SAFETY INSTRUCTIONS
a. 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.
b. 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.
c. Lower guard should 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.
4/7/09 8:23 AM Page 4
4