Hitachi CS33EDT-ND - Инструкция по эксплуатации - Страница 13

12

English

WARNING

Do not stand in-line with chain when cutting.

BASIC TECHNIQUES FOR MAKING FELLING, LIMBING AND 
BUCKING CUTS
The intention of the following information is to provide you with the 
general introduction to wood cutting techniques.

WARNING

○

  This information does not cover all speci

fi

 c situations, which may 

depend on di

ff

 erences in terrain, vegetation, kind of wood, form and 

size of trees, etc. Consult your servicing dealer, forestry agent or 
local forestry schools for advice on speci

fi

 c woodcutting problems 

in your area. This will make your work more e

ffi

  cient and safer.

○

  Avoid cutting in adverse weather conditions, such as dense fog, 

heav y rain, bitter cold, high winds, etc.

Adverse weather is often tiring to work in and creates potentially 
dangerous conditions such as slipper y ground. 

High winds may force the tree to fall in an unexpected direction 
causing proper ty damage or personal injur y.

CAUTION

Never use a chain saw to pr y or for any purpose for which it is not 
intended.

WARNING

○

  Avoid stumbling on obstacles such as stumps, roots, rocks, 

branches and fallen trees. Watch out for holes and ditches. Be 
extremely cautious when working on slopes or uneven ground.

 Shut 

o

ff

  the saw when moving from one work place to another.

Always cut at wide open throttle. A slow moving chain can easily 
catch and force the saw to jerk.

○

  Never use the saw with only one hand.

You cannot control the saw properly and you may lose control 
and injure yourself severely.

Keep the saw body close to your body to improve control and 
reduce strain.

When cutting with the bottom par t of the chain the reactive force 
will pull the saw away from you towards the wood you are cutting.

The saw will control the feeding speed and sawdust will be 
directed towards you. (

Fig.

19

)

○

  When cutting with the upper par t of the chain the reactive force 

will push the saw towards you and away from the wood you are 
cutting. (

Fig.

20

)

○

  There is a risk of kickback if the saw is pushed far enough so that 

you begin to cut with the nose of the bar.

The safest cutting method is to cut with the bottom par t of the 
chain. Sawing with the upper par t makes it much more di

ffi

  cult to 

control the saw and increases the risk of kickback.

○

  In case the chain locked, immediately release the throttle trigger.

If the throttle trigger keeps rotating at high speed with the chain 
locked, the clutch will overheat causing trouble.

NOTE

Always keep the spiked bumper face to a tree, because the 
chain may suddenly be drawn into a tree.

FELLING

Felling is more than cutting down a tree. You must also bring it down 
as near to an intended place as possible without damaging the tree 
or any thing else.
Before felling a tree, carefully consider all conditions which may 
e

ff

 ect the intended direction, such as:

Angle of the tree. Shape of the crown. Snow load on the crown.
Wind conditions. Obstacles within tree range (e.g., other trees, 
power lines, roads, buildings, etc.).

WARNING

○

  Always obser ve the general conditions of the tree. Look for 

decay and rot in the trunk which will make it more likely to snap 
and star t to fall before you expect it.

○

  Look for dr y branches, which may break and hit you when you 

are working.

Always keep animals and people at least twice the tree length 
away while felling. Clear away shrubs and branches from around 
the tree.

Prepare a path of retreat away from the felling direction.

BASIC

RULES

FOR

FELLING

TREES

Normally the felling consists of two main cutting operations, notching 
and making the felling cut. Star t making the upper notch cut on the 
side of the tree facing the feeling direction. Look through the ker f as 
you saw the lower cut so you do not saw too deep into the trunk. The 
notch  should  be  deep  enough  to  create  a  hinge  of  su

ffi

  cient  width 

and strength. The notch opening should be wide enough to direct 
the fall of the tree as long as possible. Saw the felling cut from the 
other side of the tree between one and two inches (3 – 5 cm) above 
the edge of the notch. (

Fig.

21

)

19. Felling direction
20.  45° minimum notch opening
21. Hinge
22. Felling cut

Never saw completely through the trunk. Always leave a hinge.
The hinge guides the tree. If the trunk is completely cut through, you 
lose control over the felling direction.
Inser t a wedge or a felling lever in the cut well before the tree 
becomes unstable and star ts to move. This will prevent the guide 
bar from binding in the felling cut if you have misjudged the falling 
direction.  Make  sure  no  people  have  come  into  the  range  of  the 
falling tree before you push it over.

FELLING

CUT,

TRUNK

DIAMETER

MORE

THAN

T WICE

GUIDE

BAR

LENGTH

Cut a large, wide notch. Then cut a recess into the center of the 
notch. Always leave a hinge on both sides of the center cut. (

Fig.

22

)

Complete the felling cut by sawing around the trunk as in the 

Fig.

23

.

WARNING

These methods are extremely dangerous because they involve 
the use of the nose of guide bar and can result in kickback.

Only properly trained professionals should attempt these 
techniques.

LIMBING

Limbing is removing the branches from a feller tree.

WARNING

A majority of kickback accidents occur during Iimbing.

Do not use the nose of the guide bar. Be extremely cautious and 
avoid contacting the log, other limbs or objects with the nose 
of the guide bar. Be extremely cautious of limbs under tension. 
They can spring back towards you and cause loss of control 
resulting in injur y. (

Fig.

24

)

Stand on the left side of the trunk. Maintain a secure footing and 
rest the saw on the trunk. Hold the saw close to you so that you are 
in  full  control  of  it.  Keep  well  away  from  the  chain.  Move  only  when 
the trunk is between you and the chain. Watch out for spring back of 
limbs under tension.

LIMBING

THICK

BRANCHES

When limbing thick branches, the guide bar may get pinched easily. 
Branches under tension often snap up, so cut troublesome branches 
in small steps. Apply the same principles as for cross cutting. Think 
ahead and be aware of the possible consequences of all your actions.

CROSS

CUT TING/BUCKING

Before star ting to cut through the log, tr y to imagine what is going to 
happen. Look out for stresses in the log and cut through it in such a 
manner that the guide bar will not get pinched.

CROSS

CUT TING

LOGS,

PRESSURE

ON

TOP

Take a 

fi

 rm stance. Begin with an upper cut. Do not cut too deeply, 

about 1/3 of the log diameter is enough. Finish with a bottom cut. 
The saw cuts should meet. (

Fig.

25

)

23. Relieving cut
24. Cross cut
25.  Pressure on top
26. Pressure side
27. Tension side
28.  Relative depth of saw cuts

000Book̲CS33EDT̲EE.indb   12

000Book̲CS33EDT̲EE.indb   12

2011/08/06   8:57:19

2011/08/06   8:57:19