7
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.
9. 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.
10. 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.
11. 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.
12. 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.
To avoid kickback, do support board or panel near
the cut. (Fig. 2)
Do not support board or panel away from the cut.
(Fig. 3)
13. Do not use dull or damaged blades. Unsharpened
or improperly set blades produce narrow kerf causing
excessive friction, blade binding and kickback.
14. 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.
15. Use extra caution when sawing into existing walls
or other blind areas. The protruding blade may cut
objects that can cause kickback.
16. ALWAYS hold the tool firmly with both hands.
NEVER place your hand or fingers behind the saw.
If kickback occurs, the saw could easily jump
backwards over your hand, leading to serious
personal injury. (Fig. 4)
17. Never force the saw. Push the saw forward at a
speed so that the blade cuts without slowing.
Forcing the saw can cause uneven cuts, loss of
accuracy, and possible kickback.
Lower guard function
18. 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.
19. 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.
20. 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.
21. 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.
22. To check lower guard, open lower guard by hand,
then release and watch guard closure. Also check
to see that retracting handle does not touch tool
housing. Leaving blade exposed is VERY
DANGEROUS and can lead to serious personal injury.
Additional safety warnings
23. Use extra caution when cutting damp wood,
pressure treated lumber, or wood containing
knots. Maintain smooth advancement of tool without
decrease in blade speed to avoid overheating the
blade tips.
24. Do not attempt to remove cut material when blade
is moving. Wait until blade stops before grasping
cut material. Blades coast after turn off.
25. Avoid cutting nails. Inspect for and remove all
nails from lumber before cutting.
26. Place the wider portion of the saw base on that
part of the workpiece which is solidly supported,
not on the section that will fall off when the cut is
made. As examples, Fig. 5 illustrates the RIGHT
way to cut off the end of a board, and Fig. 6 the
WRONG way. If the workpiece is short or small,
clamp it down. DO NOT TRY TO HOLD SHORT
PIECES BY HAND!
27. Before setting the tool down after completing a
cut, be sure that the lower guard has closed and
the blade has come to a complete stop.
28. Never attempt to saw with the circular saw held
upside down in a vise. This is extremely
dangerous and can lead to serious accidents.
(Fig. 7)
29. Some material contains chemicals which may be
toxic. Take caution to prevent dust inhalation and
skin contact. Follow material supplier safety data.
30. Do not stop the blades by lateral pressure on the
saw blade.
31. Do not use any abrasive wheels.
