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TYPES OF CUTTING
A. BASIC CUTTING TECHNIQUE
1. IMPORTANT POINTS.
a. Cut wood only. Do not cut metal, plastics,
masonry, non-wood,buildingmateriels; etc.
b. Stop the saw if the chain strikes a foreign
object. Inspect the unit and repair or replace
parts as necessary.
c. Keep the chain out of dirt and sand. Even a
small amount of dirt will quickly dull a chain and
thus, increase the possibility of kickback.
L_.KICKBACK WARNING
Kickback can occur when the moving chain contacts an
object at the upper portion ofthe tip ofthe guide bar or
Whenthe wood closes in and pinches the saw chain in
the cut. Contact at the upper portion of the tip of the
guide bar can cause the chainto dig into the object and
stop the chain for an instant. The result is a lightning
f_S_,reverse reaction which kicks the guide bar up and
back toward the operator, If the saw chain is pinched
along the top of the guide bar, the guide bar can be
driven rapidly back toward the operator. Either ofthese
reactions can cause loss of saw control which can
result in serious personal injury.
2. UNDERSTAND REACTIVE FORCES
Pinch-Kickback and Pun-In occur when the chain
issuddenly stopped by being pinched, caught, or
by contacting a foreign object in the wood. This
results in a reversal ofthe chainforceusedto cutwood
and causes thesaw tomove in the opposite direction of
chain rotation. Either reaction can result in loseofcon-
trol and possibleserious personal injury.
• Pinch-Kickback
---occurs when the chain, on top ofthe bar issuddenly
stopped when the top of the bar is used for cutting.
--rapidly drives the saw straight back toward the
operator.
• Pull-In-
-- can occur when the chain on the bottom of the
bar is suddenly stopped.
--pul/s thesaw rapid/yforward,
3. PROCEDURE
Practicecuttinga few small logsusingthefollowing techn_
que togetthe 'feel" ofusingyoursaw beforeyoubegin
majorsawing operation.
a. Accelerate the engine to full throttle just before
entering the cut by squeezing the throttletrigger.
b. Begin cutting with the spur against the log.
Figure20.
c. Keep the engine at full threttle the enUre time you
are cutting.
d. Allow the chain to cut for you; exert only light
downward pressure. Ifyou force thecut, damage to
the bar,chain,or engine can result.
e. Release the throttle trigger as soon as the cut is
completed, allowing theengine toidle.Ifyourunthe
saw at full throttlewithout a cuttingload, unnecessary
wear can occurtothe chain, bar,and engine.
f. Do not put pressure on thesawat theend ofthecut
to avoidlosing control whenthe cut is complete.
g. Stop the engine before setting thesaw down after
cutting.
/(
BEGIN CUTTING WITH.THE
_ _rj'. ISPUR=AGAINST LOG.
Figure 20
B. TREE FELLING TECHNIQUES
1. PLAN YOUR SAWING OPERATION CARE-
FULLY IN ADVANCE
e. Clear the work area. You need a clear area all
around the tree where you can have secure
footing.
b. Study the naturel conditions that can cause
the tree to fall in a particular direction:
1.) TheWlNDdiroctionandspeed
2.) The LEAN ofthetree
3.) WEIGHTED withBRANCHES on one side
4.) Surrounding'TREES and OBSTACLES
c. Look for decay and rot, If the trunk is rotted,
itcould snap and fall toward the operator.
d. Check for broken or dead branches which
could fall on you while cutting.
e. Make sure there isenough room for the tree
to fall. Maintaining a distance of 21/2 tree
lengths from the nearest person or other ob-
jects. Engine noise may drown out warning
call.
f. Remove dirt, stones, loose bark, nails,
staples, and wire from the tree where cuts
are to be made.
g. Plan to stand on the up-hill side when cut-
ting on a slope.
h. Plan a clear retreat path to the rear and
diagonal to the line of fall. Figure21.
12
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