Makita 5903RKX1 Instruction Manual page 6

6. When ripping, always use a rip fence or straight
edge guide. This improves the accuracy of cut and
reduces the chance of blade binding.
7. 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.
8. 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.
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 kick-
back 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 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. (Fig. 2 & 3)
13. Do not use dull or damaged blades. Unsharpened
or improperly set blades produce narrow kerf caus-
ing 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 per-
sonal injury. (Fig. 4)
6
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 posi-
tion. 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 prop-
erly, 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 "com-
pound 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 automati-
cally.
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 per-
sonal injury.
Riving knife function
23. Use the appropriate saw blade for the riving
knife. For the riving knife to function, the body of the
blade must be thinner than the riving knife and the
cutting width of the blade must be wider than the
thickness of the riving knife.
24. Adjust the riving knife as described in this
instruction manual. Incorrect spacing, positioning
and alignment can make the riving knife ineffective
in preventing kickback.
25. Always use the riving knife except when plunge
cutting. Riving knife must be replaced after plunge
cutting. Riving knife causes interference during
plunge cutting and can create kickback.
26. For the riving knife to work, it must be engaged
in the workpiece. The riving knife is ineffective in
preventing kickback during short cuts.
27. Do not operate the saw if riving knife is bent.
Even a light interference can slow the closing rate of
a guard.
Additional safety warnings
28. 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.