Ryobi CS-1840, Owner'S Operating Manual

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horizontal notching cut.
1. Pick your escape route (or routes in case the intended
route is blocked). Clear the immediate area around the
tree and make sure there are no obstructions in your
planned path of retreat. Clear the path of safe retreat
approximately 135 ° from the planned line of fall.
2. Consider the force and direction of the wind, the lean
and balance of the tree, and the location of large limbs.
These things influence the direction in which the tree
will fall. Do not try to fell a tree along a line different
from its natural line of fall.
3. Cut a notch about 1/3 the diameter of the trunk in the
side of the tree. Make the notch cuts 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.
4. Make the back cut level and horizontal, and at a
minimum of 50mm above the horizontal cut of the
notch.
Note: Never cut through to the notch. Always leave a band
of wood between the notch and back cut (approximately
50mm or 1/10 the diameter of the tree). This is called a
“hinge” or “hinge wood.” It controls the fall of the tree and
prevents slipping or twisting or shooting back of the tree
off the stump.
5. 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. Drive
wedges in, little by little, to help jack the tree over.
6. As the 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.
WARNING! Never cut through to the notch when making a
back cut. The hinge controls the fall of the tree, this is the
section of wood between the notch and back cut.
Warning! Do Not Fell Trees
• If you can no longer distinguish details within the danger
zone, e.g., owing to fog, rain or twilight.
• If the direction of fall cannot be estimated owing to wind
or gusts of wind.
• If you are unable to get a firm foothold while working on
slooping ground, black ice, frozen or dewy ground.
Removing Buttress Roots (Fig. 17)
A buttress root is a large root extending from the trunk of
the tree above the ground. Remove large buttress roots
prior to felling. Make the horizontal cut into the buttress
first, followed by the vertical cut. Remove the resulting
loose section from the work area. Follow the correct tree
felling procedure as stated in FELLING TREES after you
have removed the large buttress roots.
Bucking (Fig. 18)
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. Refer to Kickback in the Specific
Safety Rules section of this manual for more information.
• During bucking operations, stand on the uphill side so
that the cut-off section of the log cannot roll over you.
• Sometimes it is impossible to avoid pinching (with just
standard cutting techniques) or difficult to predict which
way a log will settle when cut.
Note: If the wood diameter is large enough for you to
insert a soft bucking wedge without touching the chain,
you should use the wedge to hold the cut open to prevent
pinching.
Overbucking (Fig. 19)
Begin from 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 (Fig. 20)
Begin from the underside 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.
Branch Trimmind And Pruning (Fig. 21, 22)
• Work slowly, keeping both hands on the saw with a firm
grip. Maintain secure footing and balance.
• Keep the tree between you and the chain while limbing.
• Do not cut from a ladder. This is extremely dangerous.
Leave this operation for professionals.
• Do not cut above chest height. A saw held higher than
chest height is difficult to control against kickback.
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.
• When pruning trees it is important not to make the flush
cut next to the main limb or trunk until you have cut off
the limb further out to reduce the weight. This prevents
stripping the bark from the main member.
• Underbuck the branch 1/3 through for your first cut.
• Overbuck the branch to drop it.
• Finish by cutting smoothly and neatly against the main
member so the bark will grow back to seal the wound.
WARNING! If the limbs to be pruned are above chest
height, hire a professional to perform the pruning.
MAINTENANCE
• Do not make any adjustments while the motor is in
motion.
• Always disconnect the electrical cord from the power
source before carrying out any assembly, adjustment or
maintenance work.
• Only the maintenance work described in these operating
instructions may be carried out. Any other maintenance
work must be carried out by an authorised service
centre.
• Do not modify the chain saw as this could jeopardize
your safety and will make the warranty null and void.
• Check the chain saw for damage. Any damaged
safety devices and parts must be repaired or replaced
immediately.
• After use, check your tool to keep it in top condition.
• Keep the cooling vents on the motor housing clean and
unobstructed at all times. Clean out accumulated
dust.