McCulloch MAC 838 - Manual (Page 11)

11
Natural conditions that can cause a tree to
fall in a particular direction include:
S
The wind direction and speed.
S The lean of the tree. The lean of a tree
might not be apparent due to uneven or
sloping terrain. Use a plumb or level to de-
termine the direction of tree lean.
S Weight and branches on one side.
S Surrounding trees and obstacles.
Look for decay and rot. If the trunk is rotted,
it can snap and fall toward the operator.
Make sure there is enough room for the tree to
fall. Maintain a distance of 2-1/2 tree lengths
from the nearest person or other objects. En-
gine noise can drown out a warning call.
Remove dirt, stones, loose bark, nails, staples,
and wire from the tree where cuts are to be
made.
Direction of Fall
45_
Plan a clear retreat path
FELLING LARGE TREES
(15 cm in diameter or larger)
The notch method is used to fell large trees.
A notch is cut on the side of the tree in the de-
sired direction of fall. After a felling cut is
made on the opposite side of tree, the tree
will tend to fall into the notch.
NOTCH CUT AND FELLING THE
TREE
S Make notch cut by cutting the top of the
notch first. Cut through 1/3 of the diameter
of the tree. Next complete the notch by cut-
ting the bottom of the notch. See illustra-
tion. Once the notch is cut remove the
notch of wood from the tree.
Notch
First cut
Second cut
Final cut here. 5 cm above
center of notch.
5 cm
5 cm
S After removing the wood from the notch,
make the felling cut on the opposite side of
the notch. This is done by making a cut about
5 cm higher than the center of the notch.
This will leave enough uncut wood between
the felling cut and the notch to form a hinge.
This hinge will help prevent the tree from fall-
ing in the wrong direction.
Opening
of felling
cut
Closing
of notch
Hinge holds tree on stump and helps
control fall
NOTE : Before felling cut is complete, use
wedges to open the cut when necessary to
control the direction of fall. To avoid kickback
or chain damage, use wood or plastic
wedges, but never steel or iron wedges.
S
Be alert to signs that the tree is ready to fall:
cracking sounds, widening of the felling cut,
or movement in the upper branches.
S As tree starts to fall, stop saw, put it down,
and get away quickly on your planned re-
treat path.
S DO NOT cut down a partially fallen tree with
your saw. Be extremely cautious with par-
tially fallen trees that may be poorly sup-
ported. When a tree doesn’t fall completely,
set the saw aside and pull down the tree with
a cable winch, block and tackle, or tractor.
CUTTING A FALLEN TREE
(BUCKING)
Bucking is the term used for cutting a fallen
tree to the desired log length.
WARNING : Do not stand on the log
being cut. Any portion can roll causing loss
of footing and control. Do not stand downhill
of the log being cut.
Important points
S Cut only one log at a time.
S Cut shattered wood very carefully; sharp
pieces of wood could be flung toward oper-
ator.
S Use a sawhorse to cut small logs. Never
allow another person to hold the log while
cutting and never hold the log with your leg
or foot.
S Do not cut in an area where logs, limbs,
and roots are tangled. Drag the logs into a
clear area before cutting by pulling out ex-
posed and cleared logs first.
TYPES OF CUTTING USED FOR
BUCKING
WARNING : If saw becomes pinched
or hung in a log, don’t try to force it out. You
can lose control of the saw resulting in injury
and/or damage to the saw. Stop the saw,
drive a wedge of plastic or wood into the cut
until the saw can be removed easily. Restart
the saw and carefully reenter the cut. Do not
attempt to restart your saw when it is pinched
or hung in a log.
Turn saw OFF and use a plastic or
wooden wedge to force cut open.