Husqvarna 340, Руководство оператора

Страница: 22 / 80

22 –
Canadian
SAFETY INSTRUCTIONS
Felling
Felling is done using three cuts. First you make the directional
cuts, which consist of the top cut and the bottom cut, then you
finish with the felling cut. By placing these cuts correctly you
can control the felling direction very accurately.
Directional cuts
To make the directional cuts you begin with the top cut. Stand
to the right of the tree and cut on the pull stroke.
Next make the bottom cut so that it finishes exactly at the end
of the top cut.
The directional cuts should run 1/4 of the diameter through
the trunk and the angle between the top cut and bottom cut
should be 45
°
.
The line where the two cuts meet is called the directional cut
line. This line should be perfectly horizontal and at right
angles (90
°
) to the chosen felling direction.
Felling cut
The felling cut is made from the opposite side of the tree and
it must be perfectly horizontal. Stand on the left side of the
tree and cut on the pull stroke.
Make the felling cut about 3-5 cm (1.5-2 inches) above the
bottom directional cut.
Use full throttle and bring the bar and chain slowly into the
tree. Make sure the tree does not start to move in the opposite
direction to your intended felling direction. Drive a wedge or
breaking bar into the cut as soon as it is deep enough.
Finish the felling cut parallel with the directional cut line so that
the distance between them is at least 1/10 of the trunk
diameter. The uncut section of the trunk is called the felling
hinge.
The felling hinge controls the direction that the tree falls in.
All control over the felling direction is lost if the felling hinge is
too narrow or non-existent, or if the directional cuts and felling
cut are badly placed.
When the felling cut and directional cut are complete the tree
should start to fall by itself or with the aid of a felling wedge or
breaking bar.
We recommend that you use a bar that is longer than the
diameter of the tree, so that you can make the felling cut and
directional cuts with single cutting strokes. See the Technical
data section to find out which lengths of bar are
recommended for your saw.
There are methods for felling trees with a diameter larger than
the bar length. However these methods involve a much
greater risk that the kickback zone of the bar will come into
contact with the tree.
!
WARNING! Unless you have special training
we advise you not to fell trees with a
diameter larger than the bar length of your
saw!