Jonsered CS 2238S Manuel D'utilisation page 18

6 Always use a fast cutting speed, i.e. full throttle.
7 Take great care when you cut with the top edge of the
bar, i.e. when cutting from the underside of the
object. This is known as cutting on the push stroke.
The chain tries to push the chain saw back towards
the user. If the saw chain is jamming, the saw may be
pushed back at you.
8 Unless the user resists this pushing force there is a
risk that the chain saw will move so far backwards
that only the kickback zone of the bar is in contact
with the tree, which will lead to a kickback. (35)
Cutting with the bottom edge of the bar, i.e. from the
top of the object downwards, is known as cutting on
the pull stroke. 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 on the pull stroke 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
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.
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 on the pull stroke.
• Cutting from below = Cutting on the push stroke.
Cutting on the push stroke 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?
18 – English
WORKING TECHNIQUES
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.
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.
The following instructions describe how to handle the
commonest 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
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.
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. (36)
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.
5451868-52 Rev. 2 2008-12-19