19
Fig. 24
Notched
Undercut
First Cut
Second Cut
1/3 Diameter
Direction of Fall
45º
Fig. 25
Felling
Back Cut
2 inches
(5 cm)
2 inches
(5 cm)
Hinge
1. Make a horizonal cut into the buttress root (Fig. 23). To prevent
the guide bar from being pinched by the weight of the wood,
always make this cut first.
2. Make a vertical cut into the buttress root (Fig. 23).
3. Remove the loose section from the work area.
Step 2: Making the Notched Undercut
This cut determines which direction the tree will fall. Always make
this cut on the side of the tree facing the direction where the tree
should fall. Make the cut at 90º to the line of fall.
1. Make a horizontal cut into the trunk of the tree (Fig. 24). The cut
should be about 1/3 the diameter of the tree and close to the
ground. To prevent the guide bar from being pinched by the
weight of the wood, always make this cut first.
2. Make a 45º cut into the trunk of the tree, above the first cut (Fig.
24). Continue cutting until the two cuts meet.
3. Remove the loose section from the work area.
Step 3: Making the Felling Back Cut
This cut fells the tree.
1. Make a horizontal cut into the opposite side of the tree from the
notched undercut (Fig. 25). Make the cut approximately 2 inches
(5 cm) above the bottom of the notched undercut (Fig. 25).
2. As the cut gets close to the notched undercut, only a thin band
of wood will support the tree. This band of wood is referred to as
the hinge (Fig. 25). The hinge helps control the fall of the tree.
Leave approximately 2 inches (5 cm) of hinge in place. Do not
cut through the hinge. Cutting through the hinge could cause the
tree to fall in any direction.
3. Periodically glance up during the felling back cut to see if the
tree is going to fall in the correct direction. If there is a chance
that the tree might not fall in the desired direction, or if the tree
might rock back and bind the chain saw, remove the guide bar
from the cut, stop the unit and use wedges to open the cut and
direct the fall (Fig. 26). Only use soft plastic or wooden wedges.
Drive the wedges into the cut slowly. Once the wedges are in
place and the cut is held open, either carefully reinsert the guide
bar and continue the cut or slowly drive the wedges in further to
push the tree over.
4. As the hinge gets smaller, the tree should begin to fall. When the
tree begins to fall, remove the chain saw from the cut, stop the
motor and set the unit down immediately. Promptly exit the area
along the retreat path, but keep watching the tree as it falls.
WARNING:
Never walk in front of a tree with a notched
undercut.
WARNING:
Always recheck the area for bystanders,
animals and obstacles before making the felling back cut.
Fig. 26
Wedge
Fig. 27
Spring Pole
DANGER:
If the tree starts to fall in the wrong direction
and binds the chain saw, leave the unit and evacuate the
area immediately! Do not try to save the chain saw!
WARNING:
Stay clear of spring poles when operating the
unit. Spring poles are branches, logs, roots or saplings that
are bent under tension by other wood (Fig. 27). When the
tension is released, spring poles can strike the operator,
causing serious injury and potentially knocking the chain
saw into the operator’s body. Use extreme caution when
cutting spring poles or when releasing the cause of tension.
Содержание RM4040
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