Black Max BM5020 Manual Del Operador página 21

 The chain saw operator should keep on the
uphill side of the terrain as the tree is likely to
roll or slide downhill after it is felled.
 Remove dirt, stones, loose bark, nails, staples,
and wire from the tree where felling cuts are to
be made.
NOTE: Before every cut, make sure the felling
sights on the saw housing are aligned with the
direction path for the tree to fall. Figure 23a shows
how the felling direction sights are used when
making the back cut.
 Notched Undercut. Cut a notch about 1/3 the
diameter of the tree as shown in figure 21. Make
the cuts of the notch so they intersect at a right
angle to the line of fall. This notch should be
cleaned out to leave a straight line. To keep the
weight of the wood off the saw, always make
the lower cut of the notch before the upper cut.
See Figure 21.
 Felling Backcut. The backcut is always made
level and horizontal, and at a minimum of 2 in.
above the horizontal cut of the notch. See Fig-
ures 21 - 22.
 Never cut through to the notch. Always leave a
band of wood between the notch and backcut
(approximately 2 in. or 1/10 the diameter of the
tree). This is called "hinge" or "hingewood." It
controls the fall of the tree and prevents slip-
ping or twisting or shoot-back of the tree off the
stump. See Figures 21 - 22.
 On large diameter trees, stop the back cut before
it is deep enough for the tree to either fall or settle
back on the stump. Then insert soft wooden or
plastic wedges into the cut so they do not touch
the chain. The wedges can be driven in, little by
little, to help jack the tree over. See Figure 23b.
NOTE: When bucking or felling with a wedge,
it may be necessary to remove the safety tip
anti-kickback nose guard to allow the bar to be
drawn through the cut. After the cut is complete,
the tip should be reinstalled immediately.
 As tree starts to fall, stop the chain saw and put
it down immediately. Retreat along the cleared
path, but watch the action in case something
falls your way. Be alert for overhead limbs or
branches that may fall and watch your footing.
OPERATION
WARNING:
Never cut through to the notch when making a
backcut. The hinge controls the fall of the tree,
this is the section of wood between the notch
and backcut.
BUCKING
See Figure 24.
Bucking is the term used for cutting a fallen tree
to the desired log length.
 Cut only one log at a time.
 Support small logs on a saw horse or another
log while bucking.
 Keep a clear cutting area. Make sure that no
objects can contact the guide bar nose and
chain during cutting, this can cause kickback.
To avoid the danger, keep the safety tip anti-
kickback device attached while cutting. Refer to
Kickback in the Specific Safety Rules section
of this manual for more information.
 When bucking on a slope, always stand on the
uphill side of the log. To maintain complete con-
trol of the chain saw when cutting through the
log, release the cutting pressure near the end of
the cut without relaxing your grip on the chain
saw handles. Do not let the chain contact the
ground. After completing the cut, wait for the
saw chain to stop before you move the chain
saw. Always stop the motor before moving from
tree to tree.
Page 21 — English
KICKBACK
Fig. 24