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.
An escape path should be planned and cleared
as necessary before cuts are started. The escape
path should extend back and diagonally to the rear
of the expected line of fall.
Before felling is started, consider the natural lean
of the tree, the location of larger branches and the
wind direction to judge which way the tree will fall.
Remove dirt, stones, loose bark, nails staples, and
wire from the tree.
Notching Undercut: Make the notch (X – W) 1/
3 the diameter of the tree, perpendicular to the direc-
tion of falls as Make the lower horizontal notching
cut first. This will help to avoid pinching either the
saw chain or the guide bar when the second notch is
being made.
Felling Back Cut: Make the felling back cut (Y) at
least 50 mm higher than the horizontal notching cut.
Keep the felling back cut parallel to the horizontal
notching cut. Make the felling back cut so enough
wood is left to act as a hinge. The hinge wood keeps
the tree from twisting and falling in the wrong direc-
tion. Do not cut through the hinge.
As the felling gets close to the hinge the tree should
begin to fall. If there is any chance that the tree may
not fall in desired direction or it may rock back and
bind the saw chain, stop cutting before the felling
back cut is complete and use wedges of wood, plas-
tic or aluminium to open the cut and drop the tree
along the desired line of fall.
When the tree begins to fall remove the chain saw
from the cut, stop the motor, put the chain saw
down, then use the retreat path planned. Be alert for
overhead limbs falling and watch your footing.
To complete the felling operation, drive a wedge (Z)
into the horizontal cut.
Beware of falling branches when the tree starts to
move.
Limbing a Tree
Limbing is removing the branches from a fallen
J
tree. When limbing leave larger lower limbs to sup-
port the log off the ground. Remove the small limbs
in one cut as illustrated. Branches under tension
should be cut from the bottom up to avoid binding
the chain saw.
Bucking a Log
Bucking is cutting a log into lengths. It is impor-
K
tant to make sure your footing is firm and your weight
is evenly distributed on both feet. When possible,
the log should be raised and supported by the use of
limbs, logs or chocks. Follow the simple directions
for easy cutting.
When the log is supported along its entire length as
illustrated, it is cut from the top (overbuck).
22 • F016 L70 362 • TMS • 25.04.06
When the log is supported on one end, as illus-
L
trated, cut 1/3 the diameter from the underside (un-
derbuck). Then make the finished cut by overbuck-
ing to meet the first cut.
M
When the log is supported on both ends, as illus-
trated, cut 1/3 the diameter from the top overbuck.
Then make the finished cut by underbucking the
lower 2/3 to meet the first cut.
N
When bucking on a slope always stand on the
uphill side of the log, as illustrated. When "cutting
through", to maintain complete control release the
cutting pressure near the end of the cut without re-
laxing your grip on the chain saw handles. Don't 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.
Maintenance
Before any work on the machine itself, pull
the mains plug from the socket.
Note: To ensure long and reliable service, carry out
the following maintenance regularly.
Regularly check for obvious defects such as loose,
dislodged or damaged chain and chain bar, loose
fixings and worn or damaged components.
Check that covers and guards are undamaged and
correctly fitted. Carry out necessary maintenance or
repairs before using the chain saw.
If the chain saw should happen to fail despite the
care taken in manufacturing and testing, repair
should be carried out by an authorized customer
service agent.
Before returning, ensure all oil in the oil tank has
been emptied.
For all correspondence and spare parts orders, al-
ways include the 10-digit part number (TYP) from
the nameplate of the machine!
Replacing/Changing Chain and
Chain Bar
Fit the chain and chain bar as described in "Assem-
bly and Tensioning Chain".
The circular groove of the chain bar will wear partic-
ularly on the lower edge with time. When replacing
the chain turn the chain bar 180° to allow even wear,
thus extending chain bar life.
Check drive sprocket 21. If it is worn out or damaged
due to strain, have it exchanged by an authorized
Bosch service agent.
English - 7