Hitachi CS30EH, Руководство пользователя

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GB-9
G
B
Never saw completely through the trunk. Always
leave a hinge.
The hinge guides the tree. If the trunk is
completely cut through, you lose control over
the felling direction.
Insert a wedge or a felling lever in the cut well
before the tree becomes unstable and starts to
move. This will prevent the guide bar from
binding in the felling cut if you have misjudged
the falling direction. Make sure no people have
come into the range of the falling tree before
you push it over.
FELLING CUT, TRUNK DIAMETER MORE
THAN TWICE GUIDE BAR LENGTH
Cut a large, wide notch. Then cut a recess into
the center of the notch. Always leave a hinge
on both sides of the center cut. (Fig. 2-7E)
Complete the felling cut by sawing around the
trunk as in the Fig. 2-7F.
WARNINGI
These methods are extremely dangerous
because they involve the use of the nose of
guide bar and can result in kickback. Only
properly trained professionals should attempt
these techniques.
Fig. 2-7B
Fig. 2-7C
Fig. 2-7D
Fig. 2-7F
Fig. 2-7E
WARNING!
Never use the saw with only one hand.
You cannot control the saw properly and
you may lose control and injure yourself
severely.
Keep the saw body close to your body to
improve control and reduce strain.
When cutting with the bottom part of the
chain the reactive force will pull the saw
away from you towards the wood you are
cutting.
The saw will control the feeding speed
and sawdust will be directed towards you.
(Fig. 2-7B)
When cutting with the upper part of the
chain the reactive force will push the saw
towards you and away from the wood you
are cutting. (Fig. 2-7C)
WARNING!
There is a risk of kickback if the saw is
pushed far enough so that you begin to cut
with the nose of the bar.
The safest cutting method is to cut with the
bottom part of the chain. Sawing with the
upper part makes it much more difficult to
control the saw and increases the risk of
kickback.
NOTE!
Always keep the spiked bumper face to a tree,
because the chain may suddenly be drawn into
a tree.
FELLING
Felling is more than cutting down a tree. You
must also bring it down as near to an intended
place as possible without damaging the tree or
anything else.
Before felling a tree, carefully consider all
conditions which may effect the intended
direction, such as:
Angle of the tree. Shape of the crown. Snow
load on the crown. Wind conditions. Obstacles
within tree range (e.g., other trees, power lines,
roads, buildings, etc.).
WARNING!
Always observe the general conditions of
the tree. Look for decay and rot in the trunk
which will make it more likely to snap and
start to fall before you expect it.
Look for dry branches, which may break and
hit you when you are working.
Always keep animals and people at least
twice the tree length away while felling.
Clear away shrubs and branches from
around the tree.
Prepare a path of retreat away from the
felling direction.
BASIC RULES FOR FELLING TREES
Normally the felling consists of two main
cutting operations, notching and making the
felling cut.
Start making the upper notch cut on the side of
the tree facing the feeling direction. Look
through the kerf as you saw the lower cut so
you do not saw too deep into the trunk.
The notch should be deep enough to create a
hinge of sufficient width and strength. The
notch opening should be wide enough to direct
the fall of the tree as long as possible.
Saw the felling cut from the other side of the
tree between one and two inches (3-5 cm)
above the edge of the notch. (Fig. 2-7D)