Ryobi RCS3835T, Оригинальное руководство пользователя

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6 | English
enables better control of the chainsaw in unexpected
situations.
■ Only use replacement bars and chains specified
by the manufacturer.
Incorrect replacement bars and
chains may cause chain breakage and/or kickback.
■ Follow the manufacturer’s maintenance
instructions for the saw chain.
Decreasing the depth
gauge height can lead to increased kickback.
INSTRUCTIONS CONCERNING THE PROPER TECH-
NIQUES FOR BASIC FELLING, LIMBING, AND CROSS-
CUTTING
Understanding the forces within the wood
When you understand the directional pressures and
stresses inside the wood, you can reduce the “pinches”
or at least expect them during your cutting. Tension in the
wood means the
fi bers are being pulled apart and if you cut
in this area the “kerf” or cut will tend to open as the product
goes through. If a log is being supported on a saw horse
and the end is hanging unsupported over the end, then
tension is created on the upper surface due to the weight
of the overhanging log stretching the
fi bers. Likewise, the
underside of the log will be in compression and the fi bers
are being pushed together. If a cut is made in this area, the
kerf will have the tendency to close up during the cut. This
would pinch the blade.
Felling a tree
See page 347 - 348.
When bucking and felling operations are being performed
by two or more persons at the same time, the felling
operations should be separated from the bucking operation
by a distance of at least twice the height of the tree being
felled. Trees should not be felled in a manner that would
endanger any person, strike any utility line, or cause any
property damage. If the tree does make contact with any
utility line, the company should be noti
fi ed immediately.
The chainsaw operator should keep on the uphill side of
the terrain as the tree is likely to roll or slide downhill after
it is felled.
An escape path should be planned and cleared as
necessary before cuts are started. The escape path should
extend back and diagonally to the rear of the expected line
of fall.
Before felling is started, consider the natural lean of the
tree, the location of larger branches and the wind direction
to judge which way the tree will fall.
Remove dirt, stones, loose bark, nails, staples and wire
from the tree.
Do not attempt to fell trees which are rotten or have been
damaged by wind,
fi re, lightning, etc. This is extremely
dangerous and should only be completed by professional
tree surgeons.
■ Notching undercut
See page 347 - 348.
Make the notch 1/3 the diameter of the tree,
perpendicular to the direction of falls. Make the lower
horizontal notching cut first. This will help to avoid
pinching either the saw chain or the guide bar when the
second notch is being made.
■ Felling back cut
See page 347 - 348.
Make the felling back cut at least 50 mm/2 in higher
than the horizontal notching cut. Keep the felling back
cut parallel to the horizontal notching cut. Make the
felling back cut so enough wood is left to act as a hinge.
The hinge wood keeps the tree from twisting and falling
in the wrong direction. Do not cut through the hinge.
As the felling gets close to the hinge, the tree should
begin to fall. If there is any chance that the tree may
not fall in the desired direction or it may rock back and
bind the saw chain, stop cutting before the felling back
cut is complete and use wedges of wood, plastic or
aluminium to open the cut and drop the tree along the
desired line of fall.
When the tree begins to fall remove the product from
the cut, stop the engine, put the product down, then use
the retreat path planned. Be alert for overhead limbs
falling and watch your footing.
Removing buttress roots
See page 348.
A buttress root is a large root extending from the trunk of
the tree above the ground. Remove large buttress roots
prior to felling. Make the horizontal cut into the buttress
fi rst, followed by the vertical cut. Remove the resulting
loose section from the work area. Follow the correct tree
felling procedure after you have removed the large buttress
roots.
Push and pull
See page 349.
The reaction force is always opposite to the direction the
chain is moving. Thus, the operator must be ready to control
the tendency for the product to pull away (forward motion)
when cutting on the bottom edge of the bar. Engage always
fi rmly the bumper spike to avoid such movement. The
product can be pushed backwards (towards the operator)
when cutting along the top edge. To avoid this make sure
the chain is not jammed when cutting along the top edge.
Saw jammed in the cut
Stop the product and make it safe. Do not try to force the
chain and bar out of the cut as this is likely to break the
chain which may swing back and strike the operator. This
situation normally occurs because the wood is incorrectly
supported and forcing the cut to close under compression,
thereby pinching the blade. If adjusting the support does
not release the bar and chain, use wooden wedges or a
lever to open the cut and release the product. Never try
to start the product when the guide bar is already in a cut
or kerf.
Skating / Bouncing
When the chainsaw fails to dig in during a cut, the guide
bar can begin hopping or dangerously skidding along the
surface of the log or branch, possibly resulting in the loss
of control of the chainsaw. To prevent or reduce skating or
bouncing, always use the saw with both hands. Make sure
the saw chain establishes a groove for cutting.
Never cut small,
fl exible branches or brushes with your