Husqvarna 235 Manuale Utente

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WORKING TECHNIQUES
English – 17
5451546-93 Rev.4 2008-04-16
pulling chain. In this case the chain saw pulls itself 
towards the tree and the front edge of the chain saw 
body rests naturally on the trunk when cutting. Cutting 
with a pulling chain gives the operator better control 
over the chain saw and the position of the kickback 
zone.
9 Follow the instructions on sharpening and maintaining 
your bar and chain. When you replace the bar and chain 
use only combinations that are recommended by us. 
See instructions under the headings Cutting equipment 
and Technical data.
Basic cutting technique
General
• Always use full throttle when cutting!
• Reduce the speed to idle after every cut (running the 
engine for too long at full throttle without any load, i.e. 
without any resistance from the chain during cutting, 
can lead to serious engine damage).
• Cutting from above = Cutting with a pulling chain.
• Cutting from below = Cutting with pushing chain.
Cutting with a pushing chain increases the risk of kickback. 
See instructions under the heading How to avoid kickback.
Terms
Cutting = General term for cutting through wood.
Limbing = Cutting branches off a felled tree.
Splitting = When the object you are cutting breaks off 
before the cut is complete.
There are five important factors you should consider 
before making a cut:
1 Make sure the cutting equipment will not jam in the cut.
2 Make sure the object you are cutting will not split.
3 Make sure the chain will not strike the ground or any 
other object during or after cutting.
4 Is there a risk of kickback?
5 Do the conditions and surrounding terrain affect how 
safely you can stand and move about?
Two factors decide whether the chain will jam or the object 
that you are cutting will split: the first is how the object is 
supported before and after cutting, and the second is 
whether it is in tension.
In most cases you can avoid these problems by cutting in 
two stages; from the top and from the bottom. You need to 
support the object so that it will not trap the chain or split 
during cutting.
The following instructions describe how to handle the 
common situations you are likely to encounter when using 
a chain saw.
Limbing
When limbing thick branches you should use the same 
approach as for cutting.
Cut difficult branches piece by piece.
Cutting
If you have a pile of logs, each log you attempt to cut should 
be removed from the pile, placed on a saw horse or 
runners and cut individually.
Remove the cut pieces from the cutting area. By leaving 
them in the cutting area, you increase the risk for 
inadvertently getting a kickback, as well as increasing the 
risk of losing your balance while working.
The log is lying on the ground. There is little risk of the 
chain jamming or the object splitting. However there is a 
risk that the chain will touch the ground when you finish the 
cut.
Cut all the way through the log from above. Avoid letting the 
chain touch the ground as you finish the cut. Maintain full 
throttle but be prepared for what might happen. (37)
If it is possible (can you turn the log?) stop cutting about 2/
3 of the way through the log.
Turn the log and finish the cut from the opposite side.
The log is supported at one end. There is a high risk that 
it will split.
Start by cutting from below (about 1/3 of the way through).
Finish by cutting from above so that the two cuts meet.
The log is supported at both ends. There is a high risk 
that the chain will jam.
Start by cutting from above (about 1/3 of the way through).
Finish by cutting from below so that the two cuts meet.
Tree felling technique
Safe distance
The safe distance between a tree that is to be felled and 
anyone else working nearby is at least 2 1/2 tree lengths. 
Make sure that no-one else is in this ”risk zone” before or 
during felling. (38)
Felling direction
The aim is to fell the tree in a position where you can limb 
and cross-cut the log as easily as possible. You want it to 
fall in a location where you can stand and move about 
safely.
Once you have decided which way you want the tree to fall 
you must judge which way the tree would fall naturally.
Several factors affect this:
• Lean of the tree
• Bend
• Wind direction
!
WARNING! Never use a chain saw by 
holding it with one hand. A chain saw is 
not safely controlled with one hand. 
Always have a secure, firm grip around 
the handles with both hands.
IMPORTANT! If the chain jams in the cut: stop the 
engine! Don’t try to pull the chain saw free. If you do 
you may be injured by the chain when the chain saw 
suddenly breaks free. Use a lever to open up the cut 
and free the chain saw.
!
WARNING! Never attempt to cut logs 
while they are in a pile or when a couple 
of logs are lying together. Such 
procedures drastically increase the risk 
of kickback which can result in a serious 
or fatal injury.
IMPORTANT! It takes a lot of experience to fell a tree. 
Inexperienced users of chain saws should not fell trees. 
Do not attempt any task beyond your experience level!