Shindaiwa 446s Owner's/Operator's Manual page 13

Felling Trees (continued)
Felling Larger Trees
(Over 6" (15cm) diameter)
Direction of
Fall
Notch
n If a tree is otherwise healthy and not
seriously out of balance, its direction
of fall can often be encouraged by
first "notching" the tree on the side
facing the desired direction of fall.
n After the notch is completed, start
the felling cut slightly higher and on
the opposite side of the tree, away
from the direction of fall.
n The goal of the method is to leave a
sturdy wooden "hinge" for the tree to
pivot on while falling.
1. Determine the direction of fall.
Bucking
WARNING!
Always cut downed timber
from the uphill side of the
wood! Be alert for potential injury
from rolling or shifting logs! Downed
timber may shift or roll unpredictably
during cutting or handling operations!
Techniques
n If the log is well supported, start your
cut from the top of the log. Keeping
the guide bar parallel to the ground,
cut straight down but do not allow the
saw to cut into the ground.
n Cutting downed timber, or "bucking,"
increases the possibility of the wood
settling and pinching the guide bar.
Driving one or more soft plastic or
wooden bucking wedges can help
prevent bar-pinching during a cut.
Limbing
Limbing a standing tree is usually accom-
plished in the same manner as bucking,
with a third and final cut used to remove
the remaining stub of the limb.
NOTE:
When cutting unsupported logs or limbs,
starting with an underbuck cut will mini-
mize the possibility of the wood splitting
during the bucking cut.
WARNING!
Failure to leave a proper
wooden hinge during the falling or
"back cut" can cause the tree to
pinch the saw's guide bar and may
also change the direction of fall!
Wooden
Hinge
WARNING!
Always make your falling cut
Felling
parallel to the bottom cut! An angled
Cut
falling cut may cause the tree to
split, possibly changing the direction
of fall!
Wooden
Hinge
Direction
Of Fall
Bumper
Spike
n Use two cuts when bucking near the
inboard end of an unsupported log.
1. Make the first cut as an overbuck ap-
proximately 1/3 the diameter of the log.
2. Finish the job with an underbuck
coming up from beneath and joining
the first cut.
45°
Escape
Path
45°
First Cut
Second Cut
3 2
1
2. On the side of the tree facing the
direction of fall, make a single 90°
cut through approximately 1/3 of the
tree's diameter.
3. Working from the same side of the
tree and at a 45° angle to the first cut,
make your second cut in an upward
direction to remove a notch from the
tree as shown.
4. Working on the opposite side of the tree
and starting approximately 2"
(5 mm) higher than the bottom of the
notch created in steps 1-3. Set the bum-
per spike just behind the felling hinge.
Use full throttle and bring the bar and
chain slowly into the tree. Make sure
the tree does not start to move in the op-
posite direction to your intended felling
direction. Drive a wedge or breaker bar
into the cut as soon as it is deep enough.
NOTE:
If the cut appears to be closing on the bar,
use a mallet to drive one or two plastic or
wooden wedges into the cut behind the
bar.
5. When the tree begins to fall, stop the
saw, and put it down on the ground.
6. Use your retreat path to exit the area
quickly.
Second Cut (overbuck)
First Cut (underbuck)
About 1/3 of Tree Diameter
n Use two cuts when bucking the
outboard end of an unsupported
log. Your first cut should be an
underbuck, cutting upward through
approximately 1/3 the diameter of
the tree. Finally, move to the top of
the log and finish the cut by bucking
down (overbucking) to your first cut.
WARNING!
Kickback danger increases
in over-height or out of position cut-
ting! Do not overreach or attempt to
cut above shoulder height!
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