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(fig.1) When using the machine, prevent:
- cutting in conditions where the trunk could split during
cutting (wood under pressure, dry dead trees, etc):
sudden splitting can be very dangerous.
- the bar or the chain from becoming blocked in the
cutting notch: if this should occur, disconnect the
machine from the main electricity supply and try to raise
the trunk using an appropriate tool as a lever; do not
attempt to free the machine by shaking or pulling as this
could cause damage or injury.
- situations that can lead to kickback reactions.
- using the product above shoulder height
- cutting wood with foreign objects e.g. nails
(fig.1) During machine use:
- When cutting on sloping ground, always work uphill of the
trunk to avoid being hit if the trunk should roll downhill.
- When felling trees, always finish the job: a partially cut tree
could break and fall.
- At the end of each cutting operation the user will notice a
considerable change in the strength necessary for controlling
the machine. Great care must be taken not to loose control.
Below is a description of two different types of cutting
operation:
Cutting action by pulling the chain (from top to bottom)
(fig.2) can lead to dangerous sudden movement of the
machine towards the trunk with consequential loss of
control. Where possible, use the spiked bumper during
cutting operations.
Cutting action pushing the chain (from bottom to top)
(fig.3) will lead to the danger of a sudden movement of
the machine in the direction of the user, with the risk of
hitting the user, or an impact of the "kickback danger
zone" on the trunk resulting in strong kickback; extreme
care must be taken when cutting in this manner.
The safest method for using the machine, is to block the
log on a sawhorse, cutting from top to bottom, on the
portion outside the sawhorse. (fig.4)
Spiked bumper use.
Where possible, use the spiked bumper to ensure safer
cutting action: plant it in the bark or surface of the trunk in
order to maintain more control over the machine.
Below are descriptions of typical cutting procedure to be
adopted for specific situations. However, these should be
assessed each time to calculate whether the method is
most suitable or not, In order to use a method with the
least possible risk.
Trunk on the ground. (Risk of touching the ground with
the chain once the bar has passed trough the trunk).
(fig.5)
Cut from top to bottom through the whole trunk. Towards
the end of the cut, proceed very carefully to prevent the
chain from hitting the ground. If it is possible, cut 2/3 of
the trunk, roll it over, and cut the remaining third from top
to bottom to limit the risk of the chain touching the
ground.
Trunk supported at one end only (Risk of trunk
breaking during cutting action). (fig.6)
Begin the cut from underneath for about 1/3 of the
diameter, and then finish the cutting action from the top to
meet the undercut.
Trunk supported at both ends. (Risk of pinching the
chain). (fig.7)
Begin the cut from above for about 1/3 of the diameter,
and then continue from underneath to meet the overcut.
Trunk laying on a slope. Always stand on the uphill side
of the log. When ʻcutting throughʼ, to maintain complete
control, release the cutting pressure near the end of the
cut without relaxing your grip on the chainsaw handles.
Dont let the chain contact the ground.
Tree felling.
ATTENTION!: Never attempt to fell a tree if you do not
have the necessary experience, and in any case never
fell trees that have trunks with a diameter larger than the
H. CUTTING TECHNIQUES
length of the bar! This operation is reserved for expert
machine users with adequate equipment.
When felling a tree, the aim is to have the tree fall in the
most convenient position for the following limbing and
bucking operations. (Avoid trees falling on top of other
trees: Felling trees that are entangled with other trees is
a very dangerous operation).
First of all decide which is the best direction for the tree to
fall by evaluating the following: objects or other plants
around the tree, the inclination, the curve, wind direction,
and greatest branch concentration. Take into account
dead or broken branches that may break off during felling
creating a further danger risk.
ATTENTION! During tree felling operations in critical
conditions, always remove ear protection immediately
after cutting operations to be able to listen for unusual
noises and any warning signals.
Preliminary cutting operations and identifying the
retreat path.
Eliminate any branches that interfere with the job (fig.8),
starting from top to bottom, and then, always keeping the
trunk between the user and the machine eliminate the
more difficult branches afterwards, piece by piece.
Eliminate all plants that interfere with work operations and
control the area for possible obstacles (rocks, roots,
ditches,etc.) when planning the retreat path (to follow
during tree fall); Refer to the illustration (fig.9) for the
directions to be maintained (A. predicted tree fall
direction. B. Retreat path. C. Danger zone).
FELLING CUTS (fig.10)
In order to ensure that the user has complete control over
the tree fall, the cutting instructions are as follows:
The cut that controls the fall direction of the tree is to be
executed first: First of all cut the UPPER PART of the
directional notch on the side the tree must fall. Remain
on the right hand side of the tree and cut using the chain
pull method; then cut the LOWER PART that must meet
the end of the upper part. The depth of the directional
notch must be
least 45° between upper and lower cut. The meeting
point between the two sides of the notch is called
"directional cut line" This line must be perfectly horizontal
at right angles (90°) to the felling direction.
The felling cut that provokes the tree fall, is performed at
3 to 5cm above the lower part of the directional felling cut
line, finishing at a distance of 1/10 of the trunk from the
notch. Remain on the left hand side of the tree and cut
using the chain pulling method and the spiked bumper.
Check that the tree does not move in a direction other
than that predicted for the fall. As soon as possible insert
a felling lever or wedge into the cut. The uncut part of the
trunk is called the "hinge", as it is intended to guide the
tree as it falls; in cases where the cuts are not sufficient,
not straight, or have been cut through completely, the tree
fall cannot be controlled (extremely dangerous!). For this
reason the various cuts must be performed with great
precision.
When cutting operations are completed the tree will begin
to fall. Where necessary help tree fall using wedges or
felling levers.
Limbing
Once the tree has been felled, the trunk must be limbed:
in other words, the branches are removed from the trunk.
Do not underestimate this operation because the large
majority of kickback accidents occur during this stage.
For this reason pay close attention to the position of the
bar nose during cutting operations and always work on
the left hand side of the trunk.
ENGLISH - 7
1/
of the trunk diameter, with an angle of at
4
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