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Before use:
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1 Check that the chain brake works correctly and is not damaged.
2 Check that the rear right hand guard is not damaged.
3 Check that the throttle lockout works correctly and is not damaged.
4 Check that the stop switch works correctly and is not damaged.
5 Check that all handles are free from oil.
6 Check that the anti vibration system works and is not damaged.
7 Check that the muffler is securely attached and not damaged.
8 Check that all parts of the chain saw are tightened correctly and that they are not damaged or missing.
9 Check that the chain catcher is in place and not damaged.
10 Check the chain tension.
General working instructions
• To ensure that people, animals or other things cannot affect your control of the machine.
• To make sure that none of the above might come within reach of your saw or be injured by falling trees.
CAUTION! Follow the instructions above, but do not use a chain saw in a situation where you cannot call for help in case of an accident.
2 Do not use the machine in bad weather, such as dense fog, heavy rain, strong wind, intense cold, etc.
Working in bad weather is tiring and often brings added risks, such as icy ground, unpredictable felling direction, etc.
3 Take great care when removing small branches and avoid cutting bushes (i.e. cutting many small branches at the same time). Small branches can be grabbed by the chain and thrown back at you, causing serious injury.
4 Make sure you can move and stand safely. Check the area around you for possible obstacles (roots, rocks, branches, ditches, etc.) in case you have to move suddenly. Take great care when working on sloping ground.
5 Take great care when cutting a tree that is under tension. A tree that is under tension may spring back to its normal position before or after being cut. If you position yourself incorrectly or make the cut in the wrong place the tree may hit you or the machine and cause you to lose control. Both situations can cause serious personal injury.
IMPORTANT!
This section describes basic safety rules for using a chain saw. This information is never a substitute for professional skills and experience. If you get into a situation where you feel unsafe, stop and seek expert advice. Contact your chain saw dealer, service agent or an experienced chain saw user. Do not attempt any task that you are not sure you can handle!
Before using a chain saw you must understand the effects of kickback and how to avoid them. See instructions under the heading How to avoid kickback.
Before using a chain saw you must understand the difference between cutting with the top and bottom edges of the bar. See instructions under the headings
How to avoid kickback and Machine’s safety equipment.
Wear personal protective equipment. See instructions under the heading ”Personal protective equipment”.
Basic safety rules
1 Look around you:
6 Before moving your chain saw switch off the engine and lock the chain using the chain brake. Carry the chain saw with the bar and chain pointing backwards.
Fit a guard to the bar before transporting the chain saw or carrying it for any distance.
7 When you put the chain saw on the ground, lock the saw chain using the chain brake and ensure you have a constant view of the machine. Switch the engine off before leaving your chain saw for any length of time.
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WARNING! Sometimes chips get stuck in the clutch cover causing the chain to jam. Always stop the engine before cleaning.
General rules
1 If you understand what kickback is and how it happens then you can reduce or eliminate the element of surprise. By being prepared you reduce the risk.
Kickback is usually quite mild, but it can sometimes be very sudden and violent.
2 Always hold the chain saw firmly with your right hand on the rear handle and your left hand on the front handle. Wrap your fingers and thumbs around the handles. You should use this grip whether you are
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right-handed or left-handed. This grip minimizes the effect of kickback and lets you keep the chain saw under control. Do not let go of the handles!
5 In order to keep control of your saw, always maintain a firm foothold. Never work on a ladder, in a tree or on any other insecure support.
3 Most kickback accidents happen during limbing. Make sure you are standing firmly and that there is nothing in the way that might make you trip or lose your balance.
Lack of concentration can lead to kickback if the kickback zone of the bar accidentally touches a branch, nearby tree or some other object.
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 with a pushing chain. 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.
Have control over the workpiece. If the pieces you intend to cut are small and light, they can jam in the saw chain and be thrown towards you. Even if this does not need to be a danger, you may be surprised and lose control of the saw. Never saw stacked logs or branches without first separating them. Only saw one log or one piece at a time. Remove the cut pieces to keep your working area safe.
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 can lead to a kickback.
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Never use the chain saw above shoulder height and avoid cutting with the tip of the bar. Never use the chain saw one-handed!
Cutting with the bottom edge of the bar, i.e. from the top of the object downwards, is known as cutting with a 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
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4 Is there a risk of kickback?
chain use only combinations that are recommended by us. See instructions under the headings Cutting equipment and Technical data.
Basic cutting technique
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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 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.
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 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.
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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.
Cutting
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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
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inadvertently getting a kickback, as well as increasing the risk of losing your balance while working.
Start by cutting from above (about 1/3 of the way through).
Finish by cutting from below so that the two cuts meet.
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.
Tree felling technique
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!
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.
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.
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
• Arrangement of branches
• Weight of snow
• Obstacles within the reach of the tree: for example, other trees, power lines, roads and buildings.
• Look for signs of damage and rot in the stem, this makes it more probably that the tree will break and start to fall before you expect it to.
You may find you are forced to let the tree fall in its natural direction because it is impossible or dangerous to try to make it fall in the direction you first intended.
Another very important factor, which does not affect the felling direction but does affect your safety, is to make sure the tree has no damaged or dead branches that might break off and hit you during felling.
The main point to avoid is letting the tree fall onto another tree. It is very dangerous to remove a trapped tree and
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there is high accident risk. See instructions under the heading Freeing a tree that has fallen badly.
IMPORTANT! During critical felling operations, hearing protectors should be lifted immediately when sawing is completed so that sounds and warning signals can be heard.
further forward in the terrain, where you would like the tree to fall (2). Stand on the right-hand side of the tree, behind the saw, and cut with a pull stroke.
Next make the bottom cut so that it finishes exactly at the end of the top cut.
Clearing the trunk and preparing your retreat
Delimb the stem up to shoulder height. It is safer to work from the top down and to have the tree between you and the saw.
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The directional cuts should run 1/4 of the diameter through the trunk and the angle between the top cut and bottom cut should be 45
°.
The line where the two cuts meet is called the directional cut line. This line should be perfectly horizontal and at right angles (90
°) to the chosen felling direction.
Remove any undergrowth from the base of the tree and check the area for obstacles (stones, branches, holes, etc.) so that you have a clear path of retreat when the tree starts to fall. Your path of retreat should be roughly 135 degrees away from the intended felling direction.
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1 Danger zone
2 Retreat path
3 Felling direction
Felling
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WARNING! Unless you have special training we advise you not to fell trees with a diameter larger than the bar length of your saw!
Felling is done using three cuts. First you make the directional cuts, which consist of the top cut and the bottom cut, then you finish with the felling cut. By placing these cuts correctly you can control the felling direction very accurately.
Directional cuts
To make the directional cut you begin with the top cut. Aim using to the saw’s felling direction mark (1) toward a goal
Felling cut
The felling cut is made from the opposite side of the tree and it must be perfectly horizontal. Stand on the left side of the tree and cut on the pull stroke.
Make the felling cut about 1.5-2 inches (3-5 cm) above the bottom directional cut.
Finish the felling cut parallel with the directional cut line so that the distance between them is at least 1/10 of the trunk diameter. The uncut section of the trunk is called the felling hinge.
The felling hinge controls the direction that the tree falls in.
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Never work in the risk zone of the hanging trapped tree.
All control over the felling direction is lost if the felling hinge is too narrow or non-existent, or if the directional cuts and felling cut are badly placed.
When the felling cut and directional cut are complete the tree should start to fall by itself or with the aid of a felling wedge or breaking bar.
We recommend that you use a bar that is longer than the diameter of the tree, so that you can make the felling cut and directional cuts with single cutting strokes. See instructions under the heading Technical data section to find out which lengths of bar are recommended for your saw.
The safest method is to use a winch.
• Tractor-mounted
• Portable
Cutting trees and branches that are in tension
Preparations: Work out which side is in tension and where the point of maximum tension is (i.e. where it would break if it was bent even more).
Decide which is the safest way to release the tension and whether you are able to do it safely. In complicated situations the only safe method is to put aside your chain saw and use a winch.
General advice:
Position yourself so that you will be clear of the tree or branch when the tension is released.
There are methods for felling trees with a diameter larger than the bar length. However these methods involve a much greater risk that the kickback zone of the bar will come into contact with the tree.
Make one or more cuts at or near the point of maximum tension. Make as many cuts of sufficient depth as necessary to reduce the tension and make the tree or branch break at the point of maximum tension.
Never cut straight through a tree or branch that is in tension!
If you must cut across tree/limb, make two to three cuts, one inch apart, one to two inches deep.
Freeing a tree that has fallen badly
Freeing a ”trapped tree”
It is very dangerous to remove a trapped tree and there is high accident risk.
Never try to fell the tree that is trapped.
Continue to cut deeper until tree/limb bends and tension is released.
Cut tree/limb from outside the bend, after tension has been released.
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