Husqvarna 445 EPA II, 445 e, EPA II, 450 e EPA II, 450 EPA II Owner's Manual

Operator’s manual

Manuel d’utilisation

Manual de instrucciones

445 450e

Please read the operator’s manual carefully and make sure you understand the instructions before using the machine.

Lire attentivement et bien assimiler le manuel d’utilisation avant d’utiliser la machine.

Lea detenidamente el manual de instrucciones y asegúrese de entender su contenido antes de utilizar la máquina.

1151081-49 Rev.2 2008-02-27

EPA II

445e

450

EPA II

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EEEEnnnngggglllliiiisssshhhh ((((2222----44442222))

FFFFrrrreeeennnncccchhhh ((((44443333--

SSSSppppaaaannnniiiisssshhhh ((((88886666----111122227777))

))

Symbols on the machine:

WARNING! Chain saws can be dangerous! Careless or improper use can result in serious or fatal injury to the operator or others.

Please read the operator’s manual carefully and make sure you understand the instructions before using the machine.

Always wear:

• Approved protective helmet

• Approved hearing protection

• Protective goggles or a visor

KEY TO SYMBOLS

Visual check.

Protective goggles or a visor must be worn.

Refuelling.

Both of the operator ′ s hands must be used to operate the chain saw.

Never operate a chain saw holding it with one hand only.

Contact of the guide bar tip with any object must be avoided.

Tip contact may cause the guide bar to move suddenly upward and backward (so-called kickback), which may cause serious injury.

Other symbols/decals on the machine refer to special certiﬁcation requirements for certain markets.

Symbols in the operator’s manual:

Switch off the engine before carrying out any checks or maintenance. CAUTION! The start/stop switch automatically returns to run position. In order to prevent unintentional starting, the spark plug cap must be removed from the spark plug when assembling, checking and/or performing maintenance.

Filing with oil and adjusting oil ﬂow.

The chain brake must be engaged when the chain saw is started.

You will ﬁnd the following labels on your chain saw:

EPA II

The Emissions Compliance Period referred to on the Emission Compliance label indicates the number of operating hours for which the engine has been shown to meet Federal emissions requirements. Category C = 50 hours, B = 125 hours, and A = 300 hours.

Maintenance, replacement, or repair of the emission control devices and system may be performed by any nonroad engine repair establishment or individual.

Always wear approved protective gloves.

Regular cleaning is required.

2 – English

The engine exhaust from this product contains chemical known to the State

of California to cause cancer, birth

defects or other reproductive harm.

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CONTENTS

Contents

KEY TO SYMBOLS

Symbols on the machine: 2 Symbols in the operator’s manual: 2

CONTENTS

Contents 3

INTRODUCTION

Dear customer! 4

WHAT IS WHAT?

What is what on the chain saw? 5

GENERAL SAFETY PRECAUTIONS

Before using a new chain saw 6 Important 6 Always use common sense 7 Personal protective equipment 7 Machine ′ s safety equipment 7 Cutting equipment 10

ASSEMBLY

Fitting the bar and chain 17

FUEL HANDLING

Fuel 19 Fueling 20 Fuel safety 20

STARTING AND STOPPING

Starting and stopping 21

WORKING TECHNIQUES

Before use: 23 General working instructions 23 How to avoid kickback 29

MAINTENANCE

General 31 Carburetor adjustment 31 Checking, maintaining and servicing chain saw

safety equipment 31 Mufﬂer 33 Starter 34 Air ﬁlter 35 Spark plug 36 Lubricating the bar tip sprocket 36 Needle bearing lubrication 36 Cooling system 36 ”Air Injection” centrifugal cleaning 37 Winter use 37 Maintenance schedule 38

TECHNICAL DATA

Technical data 39 Bar and chain combinations 40 Saw chain ﬁling and ﬁle gauges 40 EC-declaration of conformity 40

FEDERAL EMISSION CONTROL WARRANTY STATEMENT

YOUR WARRANTY RIGHTS AND OBLIGATIONS 41

AMERICAN STANDARD SAFETY PRECAUTIONS

Safety precautions for chain saw users 42

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English

–

INTRODUCTION

Dear customer!

Congratulations on your choice to buy a Husqvarna product! Husqvarna is based on a tradition that dates back to 1689, when the Swedish King Karl XI ordered the construction of a factory on the banks of the Huskvarna River, for production of muskets. The location was logical, since water power was harnessed from the Huskvarna River to create the waterpowered plant. During over 300 years of continuous operation, the Husqvarna factory has produced a lot of different products, from wood stoves to modern kitchen appliances, sewing machines, bicycles, motorcycles etc. In 1956, the ﬁrst motor driven lawn mowers appeared, followed by chain saws in 1959, and it is within this area Husqvarna is working today.

Today Husqvarna is one of the leading manufacturers in the world of forest and garden products, with quality as our highest priority. We develop, manufacture and market high quality motor driven products for forestry and gardening as well as for building and construction industry.

Your purchase gives you access to professional help with repairs and service whenever this may be necessary. If the retailer who sells your machine is not one of our authorized dealers, ask for the address of your nearest servicing dealer.

It is our wish that you will be satisﬁed with your product and that it will be your companion for a long time. Think of this operator ′ s manual as a valuable document. By following its ′ content (using, service, maintenance etc) the life span and the second-hand value of the machine can be extended. If you ever lend or sell this machine, make sure that the borrower or buyer gets the operator ′ s manual, so they will also know how to properly maintain and use it.

Thank you for using a Husqvarna product.

Husqvarna AB has a policy of continuous product development and therefore reserves the right to modify the design and appearance of products without prior notice.

For customer assistance, contact us at our website: www.usa.husqvarna.com

4 – English

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WHAT IS WHAT?

What is what on the chain saw?

1 Cylinder cover 2 Decompression valve 3 Air purge 4 Start reminder 5 Combined start and stop switch 6 Rear handle 7 Information and warning decal 8 Fuel tank 9 Adjuster screws carburetor 10 Starter handle 11 Starter 12 Chain oil tank 13 Product and serial number plate 14 Felling direction mark 15 Front handle 16 Front hand guard

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17 Mufﬂer 18 Chain 19 Bar tip sprocket 20 Bar 21 Bumper spike 22 Chain catcher 23 Chain tensioning screw 24 Clutch cover 25 Right hand guard 26 Throttle control 27 Throttle lockout 28 Chain tensioner wheel (445e, 450e) 29 Knob (445e, 450e) 30 Operator’s manual (EPA) 31 Bar guard 32 Combination spanner

English – 5

GENERAL SAFETY PRECAUTIONS

Before using a new chain saw

• Please read this manual carefully.

• Check that the cutting equipment is correctly ﬁtted and adjusted. See instructions under the heading Assembly.

• Refuel and start the chain saw. See the instructions under the headings Fuel Handling and Starting and Stopping.

• Do not use the chain saw until sufﬁcient chain oil has reached the chain. See instructions under the heading Cutting equipment.

• Long-term exposure to noise can result in permanent hearing impairment. So always use approved hearing protection.

WARNING! Under no circumstances may the design of the machine be modiﬁed

without the permission of the manufacturer. Always use genuine accessories. Non-authorized modiﬁcations and/or accessories can result in serious personal injury or the death of the operator or others. Your warranty may not cover damage or liability caused by the use of nonauthorized accessories or replacement parts.

WARNING! A chain saw is a dangerous tool if used carelessly or incorrectly and

can cause serious, even fatal injuries. It is very important that you read and understand the contents of this operator’s manual.

WARNING! The inside of the mufﬂer contain chemicals that may be

carcinogenic. Avoid contact with these elements in the event of a damaged mufﬂer.

WARNING! Long term inhalation of the engine’s exhaust fumes, chain oil mist

and dust from sawdust can represent a health risk.

WARNING! The ignition system of this machine produces an electromagnetic

ﬁeld during operation. This ﬁeld may under some circumstances interfere with pacemakers. To reduce the risk of serious or fatal injury, we recommend persons with pacemakers to consult their physician and the pacemaker manufacturer before operating this machine.

WARNING! Never allow children to use or be in the vicinity of the machine. As the machine is equipped with a springloaded stop switch and can be started by low speed and force on the starter handle, even small children under some circumstances can produce the force necessary to start the machine. This can mean a risk of serious personal injury. Therefore remove the spark plug cap when the machine is not under close supervision.

Important

IMPORTANT! The machine is only designed for cutting wood. You should only use the saw with the bar and chain

combinations we recommend in the chapter Technical data.

Never use the machine if you are fatigued, while under the inﬂuence of alcohol or drugs, medication or anything that could affect your vision, alertness, coordination or judgement.

Wear personal protective equipment. See instructions under the heading Personal protective equipment.

Do not modify this product or use it if it appears to have been modiﬁed by others.

Never use a machine that is faulty. Carry out the checks, maintenance and service instructions described in this manual. Some maintenance and service measures must be carried out by trained and qualiﬁed specialists. See instructions under the heading Maintenance.

Never use any accessories other than those recommended in this manual. See instructions under the headings Cutting equipment and Technical data.

CAUTION! Always wear protective glasses or a face visor to reduce the risk of injury from thrown objects. A chain saw is capable of throwing objects, such as wood chips, small pieces of wood, etc, at great force. This can result in serious injury, especially to the eyes.

WARNING! Running an engine in a conﬁned or badly ventilated area can result in death due to asphyxiation or carbon monoxide poisoning.

WARNING! Faulty cutting equipment or the wrong combination of bar and saw chain increases the risk of kickback! Only use the bar/saw chain combinations we recommend, and follow the ﬁling instructions. See instructions under the heading Technical data.

6 – English

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GENERAL SAFETY PRECAUTIONS

Always use common sense

It is not possible to cover every conceivable situation you can face when using a chain saw. Always exercise care and use your common sense. Avoid all situations which you consider to be beyond your capability. If you still feel uncertain about operating procedures after reading these instructions, you should consult an expert before continuing. Do not hesitate to contact your dealer or us if you have any questions about the use of the chain saw. We will willingly be of service and provide you with advice as well as help you to use your chain saw both efﬁciently and safely. Attend a training course in chain saw usage if possible. Your dealer, forestry school or your library can provide information about which training materials and courses are available.

• Protective goggles or a visor

• Gloves with saw protection

• Trousers with saw protection

• Boots with saw protection, steel toe-cap and non-slip sole

• Always have a ﬁrst aid kit nearby.

• Fire Extinguisher and Shovel

Generally clothes should be close-ﬁtting without restricting your freedom of movement.

IMPORTANT! Sparks can come from the mufﬂer, the bar and chain or other sources. Always have ﬁre extinguishing tools available if you should need them. Help prevent forest ﬁres.

Work is constantly in progress to improve the design and technology - improvements that increase your safety and efﬁciency. Visit your dealer regularly to see whether you can beneﬁt from new features that have been introduced.

Personal protective equipment

WARNING! Most chain saw accidents happen when the chain touches the

operator. You must use approved personal protective equipment whenever you use the machine. Personal protective equipment cannot eliminate the risk of injury but it will reduce the degree of injury if an accident does happen. Ask your dealer for help in choosing the right equipment.

Machine

In this section the machine’s safety features and their function are explained. For inspection and maintenance see instructions under the heading Checking, maintaining and servicing chain saw safety equipment. See instructions under the heading, What is what?, to ﬁnd where these parts are located on your machine.

The life span of the machine can be reduced and the risk of accidents can increase if machine maintenance is not carried out correctly and if service and/or repairs are not carried out professionally. If you need further information please contact your nearest servicing dealer.

′′

s safety equipment

′′

WARNING! Never use a machine with defective safety components. Safety equipment must be inspected and maintained. See instructions under the heading Checking, maintaining and servicing chain saw safety equipment. If your machine does not pass all the checks, take the saw to a servicing dealer for repair.

Chain brake and front hand guard

Your chain saw is equipped with a chain brake that is designed to stop the chain if you get a kickback. The chain brake reduces the risk of accidents, but only you can prevent them.

• Approved protective helmet

• Hearing protection

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Take care when using your saw and make sure the kickback zone of the bar never touches any object.

English

–

GENERAL SAFETY PRECAUTIONS

• The chain brake (A) can either be activated manually (by your left hand) or automatically by the inertia release mechanism.

• The brake is applied when the front hand guard (B) is pushed forwards.

• This movement activates a spring-loaded mechanism that tightens the brake band (C) around the engine drive system (D) (clutch drum).

• The front hand guard is not designed solely to activate the chain brake. Another important feature is that it reduces the risk of your left hand hitting the chain if you lose grip of the front handle.

• To release the chain brake pull the front hand guard backwards, towards the front handle.

• Kickback can be very sudden and violent. Most kickbacks are minor and do not always activate the chain brake. If this happens you should hold the chain saw ﬁrmly and not let go.

• The way the chain brake is activated, either manually or automatically by the inertia release mechanism, depends on the force of the kickback and the position of the chain saw in relation to the object that the kickback zone of the bar strikes.

If you get a violent kickback while the kickback zone of the bar is farthest away from you the chain brake is designed to be activated by the inertia in the kickback direction.

• The chain brake must be engaged when the chain saw is started to prevent the saw chain from rotating.

•

Use the chain brake as a ”parking brake” when star ting and when moving over short distances, to reduce the risk of moving chain accidentally hitting your leg or anyone or anything close by. Do not leave the chain saw switched on with the chain brake activated for long periods. The chain saw can become very hot.

8 – English

If the kickback is less violent or the kickback zone of the bar is closer to you the chain brake is designed to be activated manually by the movement of your left hand.

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GENERAL SAFETY PRECAUTIONS

• In the felling position the left hand is in a position that makes manual activation of the chain brake impossible. With this type of grip, that is when the left hand is placed so that it cannot affect the movement of the front hand guard, the chain brake can only be activated by the inertia action.

Will my hand always activate the chain brake during a kickback?

No. It takes a certain force to move the hand guard forward. If your hand only lightly touches the front guard or slips over it, the force may not be enough to trigger the chain brake. You should also maintain a ﬁrm grip of the chain saw handles while working. If you do and experience a kickback, your hand may never leave the front handle and will not activate the chain brake, or the chain brake will only activate after the saw has swung around a considerable distance. In such instances, the chain brake might not have enough time to stop the saw chain before it touches you.

There are also certain positions in which your hand cannot reach the front hand guard to activate the chain brake; for example, when the saw chain is held in felling position.

Will my inetria activated chain brake always activate during kickback in the event of a kickback?

No. First your brake must be in working order. Testing the brake is simple, see instructions under the heading Checking, maintaining and servicing chain saw safety equipment. We recommend you do before you begin each work session. Second the kickback must be strong enough to activate the chain brake. If the chain brake is too sensitive it would activate all the time which would be a nuisance.

Will my chain brake always protect me from injury in the event of a kickback?

No. First, the chain brake must be in working order to provide the intended protection. Second, it must be activated during the kickback as described above to stop the saw chain. Third, the chain brake may be activated but if the bar is too close to you the brake might not have enough time to slow down and stop the chain before the chain saw hits you.

Only you and proper working technique can eliminate kickback and its danger.

Throttle lockout

The throttle lockout is designed to prevent accidental operation of the throttle control. When you press the lock (A) (i.e. when you grasp the handle) it releases the throttle control (B). When you release the handle the throttle control and the throttle lockout both move back to their original positions. This arrangement means that the throttle control is automatically locked at the idle setting.

Chain catcher

The chain catcher is designed to catch the chain if it snaps or jumps off. This should not happen if the chain is properly tensioned (see instructions under the heading Assembly) and if the bar and chain are properly serviced and maintained (see instructions under the heading General working instructions).

Right hand guard

Apart from protecting your hand if the chain jumps or snaps, the right hand guard stops branches and twigs from interfering with your grip on the rear handle.

Vibration damping system

Your machine is equipped with a vibration damping system that is designed to reduce vibration and make operation easier.

1151081-49 Rev.2 2008-02-27

English

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GENERAL SAFETY PRECAUTIONS

The machine ′ s vibration damping system reduces the transfer of vibration between the engine unit/cutting equipment and the machine ′ s handle unit. The body of the chain saw, including the cutting equipment, is insulated from the handles by vibration damping units.

Cutting hardwoods (most broadleaf trees) creates more vibration than cutting softwoods (most conifers). Cutting with cutting equipment that is blunt or faulty (wrong type or badly sharpened) will increase the vibration level.

WARNING! Overexposure to vibration can lead to circulatory damage or nerve

damage in people who have impaired circulation. Contact your doctor if you experience symptoms of overexposure to vibration. Such symptoms include numbness, loss of feeling, tingling, pricking, pain, loss of strength, changes in skin colour or condition. These symptoms normally appear in the ﬁngers, hands or wrists. These symptoms may be increased in cold temperatures.

Stop switch

Use the stop switch to switch off the engine.

•

requiring among other things the mufﬂer must be equipped with an approved type of spark arrestor screen.

CAUTION! The mufﬂer gets very hot during and after use. This also applies during idling. Be aware of the ﬁre hazard, especially when working near ﬂammable substances and/or vapours.

WARNING! Never use a saw without a mufﬂer, or with a damaged mufﬂer. A damaged mufﬂer may substantially increase the noise level and the ﬁre hazard. Keep ﬁre ﬁghting equipment handy. If a spark arrestor screen is required in your area, never use the saw without or with a broken spark arrestor screen.

Cutting equipment

This section describes how to choose and maintain your cutting equipment in order to:

• Reduce the risk of kickback.

• Reduce the risk of the saw chain breaking or jumping off the bar.

• Obtain optimal cutting performance.

• Extend the life of cutting equipment.

• Avoid increasing vibration levels.

General rules

Only use cutting equipment recommended by us!

See instructions under the heading Technical data.

Mufﬂer

The mufﬂer is designed to keep noise levels to a minimum and to direct exhaust fumes away from the user.

WARNING! The exhaust fumes from the engine are hot and may contain sparks

which can start a ﬁre. Never start the machine indoors or near combustible material!

In areas with a hot, dry climate there is a high risk of ﬁres. These areas are sometimes subject to government rules

10 – English

• Keep the chain’s cutting teeth properly

sharpened! Follow our instructions and use the recommended ﬁle gauge. A damaged or badly

sharpened chain increases the risk of accidents.

1151081-49 Rev.2 2008-02-27

GENERAL SAFETY PRECAUTIONS

• Maintain the correct depth gauge setting! Follow

our instructions and use the recommended depth gauge clearance. Too large a clearance increases

the risk of kickback.

• Keep the chain properly tensioned! If the chain is slack it is more likely to jump off and lead to increased wear on the bar, chain and drive sprocket.

Some terms that describe the bar and chain

To maintain the safety features of the cutting equipment, you should replace a worn or damaged bar or chain with a bar and chain combinations recommended by Husqvarna. See instructions under the heading Technical Data for a list of replacement bar and chain combinations we recommend.

Bar

• Length (inches/cm)

• Number of teeth on bar tip sprocket (T).

• Keep cutting equipment well lubricated and properly maintained! A poorly lubricated chain is more likely to break and lead to increased wear on the bar, chain and drive sprocket.

Cutting equipment designed to reduce kickback

WARNING! Faulty cutting equipment or the wrong combination of bar and saw

chain increases the risk of kickback! Only use the bar/saw chain combinations we recommend, and follow the ﬁling instructions. See instructions under the heading Technical data.

The only way to avoid kickback is to make sure that the kickback zone of the bar never touches anything.

By using cutting equipment with ”built-in” kickback reduction and keeping the chain sharp and wellmaintained you can reduce the effects of kickback.

Bar

The smaller the tip radius the lower the chance of kickback.

Chain

A chain is made up of a number of links, which are available in standard and low-kickback versions.

IMPORTANT! No saw chain design eliminates the danger of kickback.

• Chain pitch (inches). The spacing between the drive links of the chain must match the spacing of the teeth on the bar tip sprocket and drive sprocket.

• Number of drive links. The number of drive links is determined by the length of the bar, the chain pitch and the number of teeth on the bar tip sprocket.

• Bar groove width (inches/mm). The groove in the bar must match the width of the chain drive links.

• Chain oil hole and hole for chain tensioner. The bar must be matched to the chain saw design.

Chain

• Chain pitch (inches)

WARNING! Any contact with a rotating saw chain can cause extremely serious

injuries.

1151081-49 Rev.2 2008-02-27

English

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GENERAL SAFETY PRECAUTIONS

• Drive link width (mm/inches)

• Number of drive links.

Sharpening your chain and adjusting depth gauge setting

General information on sharpening cutting teeth

• Never use a blunt chain. When the chain is blunt you have to exert more pressure to force the bar through the wood and the chips will be very small. If the chain is very blunt it will produce wood powder and no chips or shavings.

• A sharp chain eats its way through the wood and produces long, thick chips or shavings.

3 File position

4 Round ﬁle diameter

It is very difﬁcult to sharpen a chain correctly without the right equipment. We recommend that you use our ﬁle gauge. This will help you obtain the maximum kickback reduction and cutting performance from your chain.

See instructions under the heading Technical data for information about sharpening your chain.

WARNING! Departure from the sharpening instructions considerably increases the risk of kickback.

Sharpening cutting teeth

• The cutting part of the chain is called the cutter and consists of a cutting tooth (A) and the depth gauge (B). The cutters cutting depth is determined by the difference in height between the two (depth gauge setting).

When you sharpen a cutting tooth there are four important factors to remember.

1 Filing angle

2 Cutting angle

12 – English

To sharpen cutting teeth you will need a round ﬁle and a ﬁle gauge. See instructions under the heading Technical data for information on the size of ﬁle and gauge that are recommended for the chain ﬁtted to your chain saw.

• Check that the chain is correctly tensioned. A slack chain will move sideways, making it more difﬁcult to sharpen correctly.

• Always ﬁle cutting teeth from the inside face. Reduce the pressure on the return stroke. File all the teeth on one side ﬁrst, then turn the chain saw and ﬁle the teeth on the other side.

1151081-49 Rev.2 2008-02-27

GENERAL SAFETY PRECAUTIONS

• File all the teeth to the same length. When the length of the cutting teeth is reduced to 0.16 inch (4 mm) the chain is worn out and should be replaced.

General advice on adjusting depth gauge setting

• When you sharpen the cutting tooth (A) the depth gauge setting (C) will decrease. To maintain optimal cutting performance the depth gauge (B) has to be ﬁled down to achieve the recommended depth gauge setting. See instructions under the heading Technical data to ﬁnd the correct depth gauge setting for your particular chain.

WARNING! The risk of kickback is increased if the depth gauge setting is

too large!

Adjustment of depth gauge setting

• The cutting teeth should be newly sharpened before adjusting the depth gauge setting. We recommend that you adjust the depth gauge setting every third time you sharpen the cutting teeth. NOTE! This recommendation assumes that the length of the cutting teeth is not reduced excessively.

• You will need a ﬂat ﬁle and a depth gauge tool. We recommend that you use our depth gauge tool to acheive the correct depth gauge setting and bevel for the depth gauge.

Tensioning the chain

WARNING! A slack chain may jump off the bar and cause serious or even fatal injury.

The more you use a chain the longer it becomes. It is therefore important to adjust the chain regularly to take up the slack.

Check the chain tension every time you refuel. NOTE! A new chain has a running-in period during which you should check the tension more frequently.

Tension the chain as tightly as possible, but not so tight that you cannot pull it round freely by hand.

445, 450

• Loosen the bar nut that holds the clutch cover and chain brake. Use the combination spanner. Then retighten the bar nut as tightly as you can by hand.

• Raise the tip of the bar and stretch the chain by tightening the chain tensioning screw using the combination spanner. Tighten the chain until it does not sag from the underside of the bar.

• Place the depth gauge tool over the chain. Detailed information regarding the use of the depth gauge tool, will be found on the package for the depth gauge tool. Use the ﬂat ﬁle to ﬁle off the tip of the depth gauge that protrudes through the depth gauge tool. The depth gauge setting is correct when you no longer feel resistance as you draw the ﬁle along the depth gauge tool.

1151081-49 Rev.2 2008-02-27

• Use the combination spanner to tighten the bar nuts while lifting the tip of the bar at the same time. Check that you can pull the chain round freely by hand and that it does not sag from the underside of the bar.

The position of the chain tensioning screw on our chain saws varies from model to model. See instructions under the heading What is what? to ﬁnd out where it is on your model.

English – 13

GENERAL SAFETY PRECAUTIONS

445e, 450e

• Release the knob by folding it out.

• Turn the knob anti clockwise to loosen the bar cover.

• Adjust the tension on the chain by turning the wheel down (+) for tighter tension and up (-) to loosen the tension.

• Fold the knob back in to lock the tensioning.

Lubricating cutting equipment

WARNING! Poor lubrication of cutting equipment may cause the chain to snap, which could lead to serious, even fatal injuries.

Chain oil

Chain oil must demonstrate good adhesion to the chain and also maintain its ﬂow characteristics regardless of whether it is warm summer or cold winter weather.

As a chain saw manufacturer we have developed an optimal chain oil which has a vegetable oil base. We recommend the use of our own oil for both maximum chain life and to minimise environmental damage. If our own chain oil is not available, standard chain oil is recommended.

Never use waste oil! Using waste oil can be dangerous to you and damage the machine and environment.

• Tighten the bar clutch by turning the knob clockwise.

14 – English

IMPORTANT! When using vegetable based saw chain oil, dismantle and clean the groove in the bar and saw chain before long-term storage. Otherwise there is a risk of the saw chain oil oxidizing, which will result in the saw chain becoming stiff and the bar tip sprocket jamming.

Filling with chain oil

• All our chain saws have an automatic chain lubrication system. On some models the oil ﬂow is also adjustable.

• The saw chain oil tank and the fuel tank are designed so that the fuel runs out before the saw chain oil.

However, this safety feature requires that you use the right sort of chain oil (if the oil is too thin it will run out before the fuel), and that you adjust the carburetor as recommended (a lean mixture may mean that the fuel lasts longer than the oil) and that you also use the recommended cutting equipment (a bar that is too long will use more chain oil).

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GENERAL SAFETY PRECAUTIONS

Checking chain lubrication

• Check the chain lubrication each time you refuel. See instructions under the heading Lubricating the bar tip sprocket.

Aim the tip of the bar at a light coloured surface about 20 cm (8 inches) away. After 1 minute running at 3/4 throttle you should see a distinct line of oil on the light surface.

If the chain lubrication is not working:

• Check that the oil channel in the bar is not obstructed. Clean if necessary.

• Check that the groove in the edge of the bar is clean. Clean if necessary.

Chain drive sprocket

The clutch drum is ﬁtted with one of the following drive sprockets:

A Spur sprocket (the chain sprocket is welded on the drum)

B Rim sprocket (replaceable)

Regularly check the degree of wear on the drive sprocket. Replace if wear is excessive. Replace the drive sprocket whenever you replace the chain.

Needle bearing lubrication

Both versions of sprockets have a needle bearing on the drive shaft, which has to be greased regularly (once a week). CAUTION! Use only high quality bearing grease or engine oil.

See instructions under the heading Maintenance, Needle bearing lubrication.

Checking wear on cutting equipment

• Check that the bar tip sprocket turns freely and that the lubricating hole in the tip sprocket is not blocked. Clean and lubricate if necessary.

If the chain lubrication system is still not working after carrying out the above checks and associated measures you should contact your servicing dealer.

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Check the chain daily for:

• Visible cracks in rivets and links.

• Whether the chain is stiff.

• Whether rivets and links are badly worn. Replace the saw chain if it exhibits any of the points

above. We recommend you compare the existing chain with a

new chain to decide how badly the existing chain is worn. When the length of the cutting teeth has worn down to

only 0.16 inch (4 mm) the chain must be replaced.

English – 15

GENERAL SAFETY PRECAUTIONS

Bar

Check regularly:

• Whether there are burrs on the edges of the bar. Remove these with a ﬁle if necessary.

• Whether the groove in the bar has become badly worn. Replace the bar if necessary.

• Whether the tip of the bar is uneven or badly worn. If a hollow forms on the underside of the bar tip this is due to running with a slack chain.

• To prolong the life of the bar you should turn it over regularly.

WARNING! Most chain saw accidents happen when the chain touches the operator.

Wear personal protective equipment. See instructions under the heading Personal protective equipment.

Do not tackle any job that you feel you are not adequately trained for. See instructions under the headings Personal protective equipment, How to avoid kickback, Cutting equipment and General working instructions.

Avoid situations where there is a risk of kickback. See instructions under the heading Machine

Use the recommended protective equipment and check its condition. See instructions under the heading General working instructions.

Check that all the chain saw safety features are working. See instructions under the headings General working instructions and General safety precautions.

′′′′s safety equipment.

16 – English

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ASSEMBLY

Fitting the bar and chain

WARNING! Always wear gloves, when working with the chain.

445, 450

Check that the chain brake is in disengaged position by moving the front hand guard towards the front handle.

Remove the bar nuts and remove the clutch cover (chain brake). Take off the transportation ring (A).

Tension the chain by turning the chain tensioning screw clockwise using the combination spanner. The chain should be tensioned until it does not sag from the underside of the bar.

The chain is correctly tensioned when it does not sag from the underside of the bar, but can still be turned easily by hand. Hold up the bar tip and tighten the bar nuts with the combination spanner.

When ﬁtting a new chain, the chain tension has to be checked frequently until the chain is run-in. Check the chain tension regularly. A correctly tensioned chain ensures good cutting performance and long life.

Fit the bar over the bar bolts. Place the bar in its rearmost position. Place the chain over the drive sprocket locate it in the groove on the bar. Begin on the top edge of the bar.

Make sure that the edges of the cutting links are facing forward on the top edge of the bar.

Fit the clutch cover and locate the chain adjuster pin in the hole in the bar. Check that the drive links of the chain ﬁt correctly over the drive sprocket and that the chain is correctly located in the groove in the bar. Tighten the bar nuts ﬁnger tight.

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445e, 450e

Check that the chain brake is in disengaged position by moving the front hand guard towards the front handle.

Loosen the chain tensioner wheel and remove the clutch cover (chain brake). Remove the transport guard.

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ASSEMBLY

Fit the bar over the bar bolts. Place the bar in its rearmost position. Place the chain over the drive sprocket locate it in the groove on the bar. Begin on the top edge of the bar.

Make sure that the edges of the cutting links are facing forward on the top edge of the bar.

Tension the chain by turning the wheel down (+). The chain should be tensioned until it does not sag from the underside of the bar.

The chain is correctly tensioned when it does not sag from the underside of the bar, but can still be turned easily by hand. Hold up the bar tip and tighten the bar knob by turning the knob clockwise.

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FUEL HANDLING

Fuel

Note! The machine is equipped with a two-stroke engine and must always be run using a mixture of gasoline and two-stroke oil. It is important to accurately measure the amount of oil to be mixed to ensure that the correct mixture is obtained. When mixing small amounts of fuel, even small inaccuracies can drastically affect the ratio of the mixture.

WARNING! Always ensure there is adequate ventilation when handling fuel.

Gasoline

• Use good quality unleaded gasoline.

• CAUTION! Engines equipped with catalytic

converters must be run on unleaded fuel mixtures. Leaded gasoline will destroy the catalytic

converter and it will no longer serve its purpose. The green fuel cap on saws ﬁtted with catalytic converters means that only unleaded gasoline can be used.

• The lowest recommended octane grade is 87 ((RON+MON)/2). If you run the engine on a lower octane grade than 87 so-called knocking can occur. This gives rise to a high engine temperature and increased bearing load, which can result in serious engine damage.

• When working with continuous high revs (e.g. limbing) a higher octane is recommended.

Environment fuel

HUSQVARNA recommends the use of alkylate fuel or environmental fuel for four-stroke engines blended with two-stroke oil as set out below. Note that carburetor adjustment may be necessary when changing the type of fuel (see instructions under the heading Carburetor).

Running-in

Avoid running at a too high speed for extended periods during the ﬁrst 10 hours.

Two-stroke oil

• For best results and performance use HUSQVARNA two-stroke engine oil, which is specially formulated for our air-cooled two stroke-engines.

• Never use two-stroke oil intended for water-cooled engines, sometimes referred to as outboard oil (rated TCW).

• Never use oil intended for four-stroke engines.

Mixing ratio

1:50 (2%) for all engines.

Gasoline, litre Two-stroke oil, litre

2% (1:50)

5 0,10 10 0,43/0,20 15 0,30 20 0,40 US gallon US ﬂ. oz. 1 2 1/2 2 1/2 6 1/2 5 12 7/8

Mixing

• Always mix the gasoline and oil in a clean container intended for fuel.

• Always start by ﬁlling half the amount of the gasoline to be used. Then add the entire amount of oil. Mix (shake) the fuel mixture. Add the remaining amount of gasoline.

• Mix (shake) the fuel mixture thoroughly before ﬁlling the machine’s fuel tank.

• Do not mix more than one month’s supply of fuel at a time.

• If the machine is not used for some time the fuel tank should be emptied and cleaned.

Chain oil

• We recommend the use of special oil (chain oil) with good adhesion characteristics.

• Never use waste oil. This results in damage to the oil pump, the bar and the chain.

• It is important to use oil of the right grade (suitable viscosity range) to suit the air temperature.

• In temperatures below 32°F (0°C) some oils become too viscous. This can overload the oil pump and result in damage to the oil pump components.

• Contact your service agent when choosing chain oil.

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FUEL HANDLING

Fueling

WARNING! Taking the following precautions, will lessen the risk of ﬁre:

Do not smoke and do not place any hot objects in the vicinity of fuel.

Always stop the engine and let it cool for a few minutes before refuelling.

When refuelling, open the fuel cap slowly so that any excess pressure is released gently.

Tighten the fuel cap carefully after refuelling.

Always move the machine away from the refuelling area before starting.

Clean the area around the fuel cap. Clean the fuel and chain oil tanks regularly. The fuel ﬁlter must be replaced at least once a year. Contamination in the tanks causes malfunction. Make sure the fuel is well mixed by shaking the container before refuelling. The capacities of the chain oil tank and fuel tank are carefully matched. You should therefore always ﬁll the chain oil tank and fuel tank at the same time.

WARNING! Fuel and fuel vapor are highly ﬂammable. Take care when handling fuel

and chain oil. Be aware of the risks of ﬁre, explosion and those associated with inhalation.

Fuel safety

• Never refuel the machine while the engine is running.

• Make sure there is plenty of ventilation when refuelling or mixing fuel (gasoline and 2-stroke oil).

• Move the machine at least 10 ft (3 m) from the refuelling point before starting it.

• Never start the machine:

If you have spilled fuel or chain oil on the machine. Wipe off the spillage and allow remaining fuel to evaporate.

2 If you have spilled fuel on yourself or your clothes,

change your clothes. Wash any part of your body that has come in contact with fuel. Use soap and water.

3 If the machine is leaking fuel. Check regularly for leaks

from the fuel cap and fuel lines.

WARNING! Never use a machine with visible damage to the spark plug guard and ignition cable. A risk of sparking arises, which can cause a ﬁre.

Transport and storage

• Always store the chain saw and fuel so that there is no risk of leakages or fumes coming into contact with sparks or naked ﬂames from electrical equipment, electric motors, relays/switches, boilers and the like.

• Always store fuel in an approved container designed for that purpose.

• For longer periods of storage or for transport of the chain saw, the fuel and chain oil tanks should be emptied. Ask where you can dispose of waste fuel and chain oil at your local gas station.

• Ensure the machine is cleaned and that a complete service is carried out before long-term storage.

• The bar guard must always be ﬁtted to the cutting attachment when the machine is being transported or in storage, in order to prevent accident contact with the sharp chain. Even a non-moving chain can cause serious cuts to yourself or persons you bump into with an exposed chain.

• Remove the spark plug cap from the spark plug. Activate the chain brake.

Long-term storage

Empty the fuel/oil tanks in a well ventilated area. Store the fuel in approved cans in a safe place. Fit the bar guard. Clean the machine. See instructions under the heading Maintenance schedule.

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STARTING AND STOPPING

Starting and stopping

WARNING! Note the following before starting:

The chain brake must be engaged when the chain saw is started to reduce the chance of contact with the moving chain during starting.

Never start a chain saw unless the bar, chain and all covers are ﬁtted correctly. Otherwise the clutch can come loose and cause personal injuries.

Place the machine on ﬁrm ground. Make sure you have a secure footing and that the chain cannot touch anything.

Keep people and animals well away from the working area.

Starting

The chain brake should be activated when starting the chain saw. Activate the chain brake by pushing the front hand guard forwards.

Push down the red choke control (5) as soon as the engine ﬁres which can be heard through a "puff" sound. Keep on pulling the cord powerfully until the engine starts.

Warm engine

When the chain saw is heated restart the saw only by pulling the cord powerfully until the engine starts (6).

Never wrap the starter cord around your hand

There is a simpliﬁed start reminder with illustrations to describe each step on the rear edge of the saw (A).

As the chain brake is still engaged the speed of the engine must be set to idling as soon as possible, this is achieved by disengaging the throttle lock. Disengagement is done by gently touching on the throttle trigger. This prevents unnecessary wear to the clutch, clutch drum and brake band.

Cold engine Start position (1): Set the start/stop switch in the choke

position by pulling the red control outward - upward (1). Decompression valve (2): Press the valve to reduce the

pressure in the cylinder and make starting easier. Once the machine has started the valve will automatically return to its original setting.

Air purge (3): Press the air purge diaphragm repeatedly until fuel ﬁlls the diaphragm (at least 6 times). The diaphragm need not be completely ﬁlled.

Grip the front handle with your left hand. Hold the chain saw on the ground by placing your right foot through the rear handle. Pull the starter handle with your right hand and pull out the starter cord slowly until you feel a resistance (as the starter pawls engage) then pull ﬁrmly and rapidly until the engine ﬁres (4).

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Allow the machine to idle a few seconds before giving full throttle.

CAUTION! Do not pull the starter cord all the way out and do not let go of the starter handle when the cord is fully extended. This can damage the machine.

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STARTING AND STOPPING

Note! Pull the front hand guard towards the front handle. The chain brake is now disengaged. Your saw

is ready for use.

WARNING! Long term inhalation of the engine’s exhaust fumes, chain oil mist

and dust from sawdust can represent a health risk.

• Never start a chain saw unless the bar, chain and all covers are ﬁtted correctly. See instructions under the heading Assembly. Without a bar and chain attached to the chain saw the clutch can come loose and cause serious injury.

• The chain brake should be activated when starting. Se instructions under the heading Start and stop. Do not drop start. This method is very dangerous because you may lose control of the saw.

• Always hold the saw with both hands. The right hand should be on the rear handle, and the left hand on the front handle. All people, whether right or left handed, should use this grip. Use a ﬁrm grip with thumbs and ﬁngers encircling the chain saw handles.

Stopping

Stop the engine by pushing the start/stop switch down. CAUTION! The start/stop switch automatically returns to

run position. To avoid involuntary start up, the spark plug cap must always be removed from the spark plug when the machine is unsupervised.

• Never start the machine indoors. Exhaust fumes can be dangerous if inhaled.

• Observe your surroundings and make sure that there is no risk of people or animals coming into contact with the cutting equipment.

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WORKING TECHNIQUES

Before use:

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

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:

• 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.

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English – 23

WORKING TECHNIQUES

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.

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.

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.

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 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!

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.

4 Never use the chain saw above shoulder height

and avoid cutting with the tip of the bar. Never use the chain saw one-handed!

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.

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

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WORKING TECHNIQUES

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 can lead to a kickback.

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.

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?

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 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.

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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.

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WORKING TECHNIQUES

Limbing

When limbing thick branches you should use the same approach as for cutting.

Cut difﬁcult branches piece by piece.

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.

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.

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

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.

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WORKING TECHNIQUES

Retreat path

Danger zone

r z

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 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.

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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.

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.

Felling

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 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.

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WORKING TECHNIQUES

Next make the bottom cut so that it ﬁnishes exactly at the end of the top cut.

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.

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.

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.

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.

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.

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WORKING TECHNIQUES

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. Never work in the risk zone of the hanging trapped tree.

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).

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.

Continue to cut deeper until tree/limb bends and tension is released.

Cut tree/limb from outside the bend, after tension has been released.

How to avoid kickback

WARNING! Kickback can happen very suddenly and violently; kicking the chain saw, bar and chain back at the user. If this happens when the chain is moving it can cause very serious, even fatal injuries. It is vital you understand what causes kickback and that you can avoid it by taking care and using the right working technique.

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.

Make one or more cuts at or near the point of maximum tension. Make as many cuts of sufﬁcient depth as

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What is kickback?

The word kickback is used to describe the sudden reaction that causes the chain saw and bar to jump off an object when the upper quadrant of the tip of the bar, known as the kickback zone, touches an object.

Kickback always occurs in the cutting plane of the bar. Normally the chain saw and bar are thrown backwards and upwards towards the user. However, the chain saw may move in a different direction depending on the way it

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WORKING TECHNIQUES

was being used when the kickback zone of the bar touched the object.

Kickback only occurs if the kickback zone of the bar touches an object.

Limbing

WARNING! A majority of kickback accidents occur during limbing. Do not

use the kickback zone 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 toward you and cause loss of control resulting in injury.

Cutting the trunk into logs

See instructions under the heading Basic cutting technique.

Make sure that you can stand and move about safely. Work on the left side of the trunk. Work as close as possible to the chain saw for maximum control. If possible, let the weight of the chain saw rest on the trunk.

Keep the trunk between you and the chain saw as you move along the trunk.

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