Ryobi RY40502 - Manual (Page 21)

21 - English
OPERATION
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.
■ Sometimes it is impossible to avoid pinching
(with just standard cutting techniques) or difficult
to predict which way a log will settle when cut.
To avoid pinching while cutting, rotate or move
the log so that the pinch is eliminated.
BUCKING LOGS UNDER STRESS
See Figures 19 - 20.
When the log is supported along its entire length,
it should be cut from the top or overbucking.
When the log is supported on one end, cut 1/3
the diameter from the underside or underbucking.
Then make the finishing cut by overbucking to
meet the first cut.
As the log is being cut, it will tend to bend. The
saw can become pinched or hung in the log if you
make the first cut deeper than 1/3 of the diameter
of the log.
Give special attention to logs under stress to
prevent the bar and chain from pinching.
When bucking on a slope, always stand on the
uphill side of the log as shown in figure 18. When
“cutting through,” to maintain complete control
of the chain saw, 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.
TYPES OF CUTTING USED
See Figure 20.
OVERBUCKING
Begin on the top side of the log with the bottom
of the saw against the log; exert light pressure
downward. Note that the saw will tend to pull
away from you.
UNDERBUCKING
Begin on the under side of the log with the top
of the saw against the log; exert light pressure
upward. During underbucking, the saw will tend
to push back at you. Be prepared for this reaction
and hold the saw firmly to maintain control.
WARNING:
Never climb into a tree to limb or prune. Do
not stand on ladders, platforms, a log, or in
any position which can cause you to lose your
balance or control of the saw.
LIMBING
See Figure 21.
Limbing is removing branches from a fallen tree.

Work slowly, keeping both hands on the chain
saw with a firm grip. Always make sure your
footing is secure and your weight is distributed
evenly on both feet.
 Leave the larger support limbs under the tree to
keep the tree off the ground while cutting.
Fig. 20
CUT LIMBS ONE AT A TIME AND LEAVE SUPPORT LIMBS
UNDER TREE UNTIL LOG IS CUT
Fig. 21
4
1
3
2
OVERBUCKING
UNDERBUCKING