McCulloch MAC 740 Chainsaw User Manual


 
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
slopingterrain. Useaplumborleveltode-
termine the direction of tree lean.
S Weight and branches on one side.
S Surrounding trees and obstacles.
Look for decay and rot. If thetrunk isrotted,
it can snap and fall toward the operator.
Make sure there is enough room for the treeto
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.
Removedirt, stones, loosebark, 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
(15cmindiameterorlarger)
The notch method is used to felllarge trees.
Anotchiscutonthesideofthetreeinthede-
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
ofthetree.Nextcompletethenotchbycut-
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 cmabove
center of notch.
5cm
5cm
S After removing the wood from the notch,
make the felling cut on the opposite side of
thenotch.Thisis donebymakingacutabout
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 thetree fromfall-
ing in the wrong direction.
Opening
of felling
cut
Closing
of notch
Hinge holdstree on stump and helps
control fall
NOTE: Before felling cut is complete, use
wedges to open the cut when necessary to
controlthedirectionoffall. Toavoidkickback
or chain damag e, use wood or plastic
wedges, but never steel or iron wedges.
S Bealerttosignsthatthetreeisreadytofall:
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 asideand pulldown thetreewith
a cable winch, block and tackle, or tractor.
CUTTING A F ALLEN 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 andcontrol. 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
piecesofwoodcouldbeflungtowardoper-
ator.
S Use a sawhorse to cut small logs. Never
allow another person to hold the logwhile
cuttingandneverholdthelogwithyourleg
or foot.
S Do n ot cut in an area where logs, limbs,
and roots are tangled. Drag thelogs intoa
clear area beforecutting b ypulling out ex-
posed and cleared logs first.
TYPES OF CUTTING USED FOR
BUCKING
WARNING:If saw becomespinched
or hung ina log, don’ttry t oforce it out. You
can lose controlof the saw r esulting in injury
and/or damage to the saw. Stop the saw ,
drive a wedge of plastic or wood into thecut
untilthesawcanberemovedeasily. Restart
thesawandcarefully reenterthe cut. Donot
attempttorestartyoursawwhenitispinched
or hung in a log.
Turn saw OFF and use a plastic or
wooden wedge to force cut open.