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met,
Gloves
the
–
should comply with EN381-7 and be CE marked
Leg protection (chaps)
ould
should comply with EN381-5, be CE marked and provide
–
nds
all-round protection.
Chainsaw safety boots
mple
should comply with EN ISO 20345:2004 and be marked
–
not
with a shield depicting a chainsaw to show compliance with
EN 381-3. (Occasional users may use steel toe-cap safety
arts,
boots with protective gaiters which conform to EN 381-9
tery
if the ground is even and there is little risk of tripping or
e:
catching on undergrowth)
Chainsaw jackets for upper body protection
–
should comply with EN 381-11 and be CE marked
INSTRUCTIONS CONCERNING THE PROPER TECHNIQUES
ct
FOR BASIC FELLING, LIMBING, AND CROSS-CUTTING
d as
ple,
Understanding the forces within the wood
i.e.,
When you understand the directional pressures and stresses inside
ol of
the wood you can reduce the "pinches" or at least expect them
during your cutting. Tension in the wood means the fibers are being
you
pulled apart and if you cut in this area, the "kerf" or cut will tend to
into
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
the
created on the upper surface due to the weight of the overhanging
ugh
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
y to
the cut. This would pinch the blade.
lure
Felling a tree
the
See figures 1 - 8.
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
n is
manner that would endanger any person, strike any utility line, or
ncy
cause any property damage. If the tree does make contact with any
the
utility line, the company should be notified immediately.
the
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
hain
diagonally to the rear of the expected line of fall.
may
curs
Before felling starts, consider the natural lean of the tree, the
ut to
location of larger branches, and the wind direction to judge which
ting
way the tree will fall.
den
Remove dirt, stones, loose bark, nails, staples, and wire from the
r try
tree.
erf.
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
by
See figures 1 - 6.
ator.
Make the notch 1/3 the diameter of the tree, perpendicular to
aw:
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
See figures 1 - 6.
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
fety
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 chainsaw from the cut,
stop the motor, put the chainsaw down, and use the retreat path
planned. Be alert for falling overhead limbs and watch your
footing.
Removing buttress roots
See figures 7 - 8.
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 loose section from the work area.
Follow the correct tree felling procedure after you have removed the
large buttress roots.
Bucking a log
See figures 9 - 11.
Bucking is cutting a log into lengths. It is important to make sure
your footing is firm and your weight is evenly distributed on both
feet. When possible, the log should be raised and supported by the
use of limbs, logs or chocks. Follow the simple directions for easy
cutting. When the log is supported along its entire length, it is cut
from the top (overbuck).
When the log is supported on one end, cut 1/3 the diameter from the
underside (underbuck). Then make the finished cut by overbucking
to meet the first cut.
When the log is supported on both ends, cut 1/3 the diameter from
the top (overbuck). Then make the finished cut by underbucking the
lower 2/3 to meet the first cut.
When bucking on a slope always stand on the uphill side of the
log. To maintain control when "cutting through", release the cutting
pressure near the end of the cut without relaxing your grip on the
chainsaw handles. Don't let the chain contact the ground. After
completing the cut, wait for the saw chain to stop before you move
the chainsaw. Always stop the motor before moving from tree to
tree.
Limbing a tree
See figures 12 - 13.
Limbing is removing the branches from a fallen tree. When limbing,
leave larger lower limbs to support the log off the ground. Remove
the small limbs in one cut. Branches under tension should be cut
from the bottom up to avoid binding the chainsaw.
Springpoles
See figure 14.
A springpole is any log, branch, rooted stump, or sapling which is
bent under tension by other wood so that it springs back if the wood
holding it is cut or removed.
On a fallen tree, a rooted stump has a high potential of springing
back to the upright position during the bucking cut to separate the
log from the stump. Watch out for springpoles—they are dangerous.
WARNING! Springpoles are dangerous and could strike the
operator, causing the operator to lose control of the chainsaw.
This could result in severe or fatal injury to the operator. This
should be done by trained users.
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