Hitachi CS-350A Handling Instructions Manual page 25

(3) When sawing a thick piece of wood, press the spike
on the front section of the unit against the workpiece
and cut it with lever action while using the spike
as a fulcrum as shown in Fig. 5.
(4) When cutting wood horizontally, turn the unit body
to the right so that the guide bar is below and hold
the upper side of the side handle with your left
hand. Hold the guide bar horizontally and place the
spike that is on the front of the unit body on the
lumber. Using the spike as a fulcrum, cut into the
wood by turning the handle to the right. (Fig. 6)
(5) When cutting into wood from the bottom, touch the
upper part of the guide bar to the wood lightly.
(Fig. 7)
(6) In addition of careful study of the handling
instructions, take practical instruction in the operation
of the chain saw prior to use, or at least to practice
working with the chain saw by cutting lengths of
round timber on a sawing trestle.
(7) When cutting logs or timbers which are not
supported, support them properly not to move
during cutting by a sawing trestle or another proper
methods.
CAUTIONS
When cutting wood from the bottom, there is
the danger that the unit body may pushed back
toward the user if the chain strongly hits the
wood.
Do not cut all the way through the wood by
starting from the bottom since there is the danger
of the guide bar flying up out of control when
the cut is finished.
Always prevent the operating chain saw from
touching the ground or wire fences.
2. Branch cutting
(1) Cutting branches from a standing tree:
A thick branch should initially be cut off at a point
away from the trunk of the tree.
First cut in about one third of the way from below,
and then cut off the branch from above. Finally, cut
off the remaining portion of the branch even with
the trunk of the tree. (Fig. 8)
CAUTIONS
Always be careful to avoid falling branches.
Always be alert for chain saw recoil.
(2) Cutting branches from fallen trees:
First cut off branches that do not touch the ground,
then cut off those which touch the ground. When
cutting thick branches that touch the ground, first
cut in about half of the way from above, then cut
the branch off from below. (Fig. 9)
CAUTION
When cutting off branches which touch the
ground, be careful that the guide bar does not
become bound by pressure.
In the final stage of cutting, beware of the log
suddenly rolling.
3. Log cutting
When cutting a log positioned as shown in Fig. 10,
first cut in about one third of the way from below,
then cut down all the way from above.
When cutting a log that straddles a hollow as shown
in Fig. 11, first cut in about two thirds of the way
from above, then cut upward from below.
CAUTIONS
Be careful that the guide bar does not become
bound in the log by pressure.
When working on inclined ground, be sure to
stand on the uphill side of the log. If you stand
on the downhill side, the cut-off log may roll
toward you.
4. Felling trees:
(1) Undercut (q as shown in Fig. 12):
Make undercut facing direction which you want tree
to fall.
Depth of undercut should be 1/3 of tree's diameter.
Never fell trees without proper undercut.
(2) Backcut (w as shown in Fig. 12):
Make backcut about 5 cm above and parallel to the
horizontal undercut.
If the chain is bound during cutting, stop the saw
and use wedges to free form it. Do not cut through
the tree.
CAUTIONS
Trees should not be felled in a manner that
would endanger any person, strike any utility
line or cause any property damage.
Be sure to stand on the uphill side of the terrain
as the tree is likely to roll or slide downhill after
it is felled.
SETTING OF CHAIN BLADE
CAUTION
Ensure the power source has been disconnected from the
tool before performing the steps below. Wear gloves to
protect your hands.
Dull and worn chain blades will decrease the efficiency of
the tool and place unnecessary overload on the motor
and various parts of the machine. In order to maintain
optimum efficiency, it is necessary to check the chain
blades often and keep them properly sharpened and
adjusted. Blade setting and depth gauge adjustment
should be accomplished at the center of the guide bar
with the chain properly mounted to the machine.
1. Blade setting
The accessory round file should be held against the
chain blade so that one-fifth of its diameter extends
above the top of the blade, as shown in Fig. 13.
Sharpen the blades by keeping the round file at a
30° angle in relation to the guide bar, as shown
in Fig. 14, ensuring that the round file is held
straight, as shown in Fig. 15. Ensure that all saw
blades are filed at the some angle, or the cutting
efficiency of the tool will be impaired. Appropriate
angles for correctly set blades should be as shown
in Fig. 16.
2. Adjustment of depth gauge
To perform this work, please use the optional
accessory depth gauge jointer and a standard flat
file obtainable in local markets. The dimension
shown in Fig. 17 is called the depth gauge. The
depth gauge dictates the amount of incision (cut-
in), and must be accurately maintained. The optimum
depth gauge for this tool is 0.5 mm. After repeated
blade settings, the depth gauge will be decreased.
Accordingly, after every 3–4 settings, place the depth
gauge jointer as shown in Fig. 18, and file away
that portion that protrudes above the upper plane
of the depth gauge jointer.
English
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