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Make sure the bar and the chain are
in place when you check the oil delivery.
Start the motor (par. 6.3), keep it running
at medium power and check if the chain
oil is delivered as shown in (fig. 11).
6.4.2 Work techniques
6.4.2.a Delimbing a tree
Make sure there is nothing or nobody
in the area where the branches will fall.
1. Stand opposite the branch you want to cut.
2. Start cutting lower branches
followed by the higher ones.
3. Cut downwards to prevent the bar
from getting jammed (fig. 12).
6.4.2.b Felling a tree
IMPORTANT Where two or more persons
are working together on felling and bucking
operations, such operations must be performed
in separate areas at a distance from each
other of at least 2.5 times the height of the tree
being felled. Do not fell trees if this involves
risks of injuring people, coming into contact
with a power line or causing any form of
damage. If the tree should come into contact
with a main power line, report the incident
immediately to the network provider.
Before commencing the felling operations:
– it is necessary to evaluate the natural
inclination of the tree, the part where the
branches are larger and the wind direction,
to assess how the tree will actually fall;
– remove any dirt, stones, pieces of
bark, nails, metal staples and wire;
– clear the area around the tree and
find a stable place to stand;
– plan obstacle-free escape routes at a 45°
angle back and away from the direction of
the fall (Fig. 13) which allow the operator
to escape to a safe zone, about 2.5 times
the height of the tree being felled;
– Stand uphill of the land onto which the tree
will probably roll or fall over after felling.
• Performing a face notch
1. Point towards a target on the ground in the
direction in which you intend to fell the tree.
2. Stand to the right of the tree,
behind the chain saw.
3. Saw a horizontal face notch to 1/3 of the
diameter of the tree, perpendicular to the
direction in which it will fall (Fig. 14.A).
• Felling back cut
1. Perform the felling back cut at least
5 cm higher than the horizontal
face notch (Fig. 15.B).
2. Perform the felling back cut leaving
sufficient wood to act as a "hinge" (Fig.
15.C). The hinge wood will prevent the
tree from twisting and falling in the wrong
direction. Do not cut through the hinge.
3. Reduce the thickness of this hinge without
pulling out the bar, until the tree falls.
4. If there is any risk of the tree not falling
in the desired direction, or that it might
lose its balance moving backwards and
bending the toothed chain, stop cutting
before completing the felling back cut and
use some wooden, plastic or aluminium
wedges (Fig. 16.D) to open the cut. Force
the tree to fall along the desired line by
hitting the wedges with a sledge hammer.
5. When the tree starts to fall, it is necessary to
withdraw the machine from the cut, switch
it off (par. 6.5), lie it on the ground and take
the foreseen exit route. Beware of falling
branches and pay attention where
you put your feet.
6.4.2.c Limbing tree branches
Limbing means removing the
branches from a felled tree.
Be careful of where the branches
are lying on the ground, the risk of
them being under tension, the direction
the branch may go during cutting and
the risk of the tree being unstable
after the branch has been cut.
When limbing, it is necessary to
leave the lower, larger branches to
support the trunk on the ground.
Remove the small branches with
a single cut (Fig. 17.A).
It is recommended to cut the tensioned
branches working from the bottom upwards to
prevent the chain saw from bending (Fig. 17.B).
6.4.2.d Bucking the trunk
Bucking means sawing a tree trunk into logs.
It is essential to make sure your feet are
positioned firmly on the ground, and your weight
is distributed equally on both feet. If possible,
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