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Spiked Bumper
The integral bumper spike may be used as a pivot when
making a cut. It helps to keep the body of the chain saw
steady while cutting. When cutting, push the machine
forward until the spikes dig into the edge of the wood,
then by moving the rear handle up or down in the
direction of the cutting line it can help ease the physical
strain of cutting.
Guide Bar
Generally, guide bars with small radius tips have
somewhat lower potential for kick-back. You should use a
guide bar and matching chain which is just long enough
for the job. Longer bars increase the risk of loss of control
during sawing. Regularly check the chain tension. When
cutting smaller branches (less than the full length of the
guide bar) the chain is more likely to be thrown off if the
tension is not correct.
Chain Brake
Chain brakes are designed to quickly stop the chain
from rotating. When the chain brake lever/hand guard
is pushed towards the bar, the chain should stop
immediately. A chain brake does not prevent kickback.
It only lowers the risk of injury should the chain bar
contact the operator's body during a kickback event. The
chain brake should be tested before each use for correct
operation in both the run and brake positions.
Chain Catcher
A chain catcher prevents the saw chain from being
thrown back towards the operator if the saw chain comes
loose or breaks.
Instructions concerning the proper
techniques 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 fibers are being pulled apart and if you
cut in this area, the "kerf" or cut will tend to open as the
saw goes through. If a log is being supported on a saw
horse and the end is hanging unsupported over the end,
tension is created on the upper surface due to the weight
of the overhanging log stretching the fibers. Likewise, the
underside of the log will be in compression and the fibers
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
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 notified immediately.
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 starts, 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, fire, lightning, etc. This is extremely
dangerous and should only be completed by professional
tree surgeons.
1. Notching undercut
Make the notch 1/3 the diameter of the tree,
perpendicular to the direction of the fall. 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.
2. Felling-back cut
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 chain saw
from the cut, stop the motor, put the chain saw down,
anf use the retreat path planned. Be alert for falling
overhead limbs and watch your footing.
Removing buttress roots
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
first, followed by the vertical cut. Remove the resulting
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