MAKITA UC4050A (01) PDF MANUAL

MAKITA UC4050A (01) PDF SUMMARY:

What models does this manual cover?

The instruction manual covers the following models of electric chain saws: UC3050A, UC3051A, UC3550A, UC3551A, UC4050A, UC4051A, UC4550A, and UC4551A.

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What is the intended use of this tool?

The tool is intended for cutting lumbers and logs.

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What type of power supply should be used?

The tool should be connected to a power supply with the same voltage as indicated on the nameplate and can only be operated on a single-phase AC supply. The tool is double-insulated and can be used from sockets without an earth wire.

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What are the general safety warnings for power tools?

It is important to read all safety warnings and instructions. Failure to follow the warnings and instructions may result in electric shock, fire, and/or serious injury. Save all warnings and instructions for future reference.

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What are the safety guidelines for the work area?

• Keep the work area clean and well lit. Cluttered or dark areas invite accidents.
• Do not operate power tools in explosive atmospheres, such as in the presence of flammable liquids, gases, or dust. Power tools create sparks which may ignite the dust or fumes.
• Keep children and bystanders away while operating a power tool. Distractions can cause a loss of control.

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What are the electrical safety guidelines?

• Power tool plugs must match the outlet and should never be modified. Do not use adapter plugs with earthed (grounded) power tools. Unmodified plugs and matching outlets will reduce the risk of electric shock.
• Avoid body contact with earthed or grounded surfaces such as pipes, radiators, ranges, and refrigerators. There is an increased risk of electric shock if the body is earthed or grounded.
• Do not expose power tools to rain or wet conditions. Water entering a power tool will increase the risk of electric shock.
• Do not abuse the cord. Never use the cord for carrying, pulling, or unplugging the power tool. Keep the cord away from heat, oil, sharp edges, or moving parts. Damaged or entangled cords increase the risk of electric shock.
• When operating a power tool outdoors, use an extension cord suitable for outdoor use. Using a cord suitable for outdoor use reduces the risk of electric shock.
• If operating a power tool in a damp location is unavoidable, use a residual current device (RCD) protected supply. Use of an RCD reduces the risk of electric shock.
• Using a power supply via an RCD with a rated residual current of 30mA or less is always recommended.

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What are the personal safety guidelines?

• Stay alert, watch what you are doing, and use common sense when operating a power tool. Do not use a power tool while tired or under the influence of drugs, alcohol, or medication. A moment of inattention while operating power tools may result in serious personal injury.
• Use personal protective equipment and always wear eye protection. Protective equipment such as a dust mask, non-skid safety shoes, hard hat, or hearing protection used for appropriate conditions will reduce personal injuries.
• Prevent unintentional starting. Ensure the switch is in the off-position before connecting to a power source and/or battery pack, picking up, or carrying the tool. Carrying power tools with a finger on the switch or energizing power tools that have the switch on invites accidents.
• Remove any adjusting key or wrench before turning the power tool on. A wrench or a key left attached to a rotating part of the power tool may result in personal injury.
• Do not overreach. Keep proper footing and balance at all times. This enables better control of the power tool in unexpected situations.
• Dress properly. Do not wear loose clothing or jewelry. Keep hair, clothing, and gloves away from moving parts. Loose clothes, jewelry, or long hair can be caught in moving parts.
• If devices are provided for the connection of dust extraction and collection facilities, ensure these are connected and properly used. Use of dust collection can reduce dust-related hazards.

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What are the guidelines for power tool use and care?

• Do not force the power tool. Use the correct power tool for the application. The correct power tool will do the job better and safer at the rate for which it was designed.
• Do not use the power tool if the switch does not turn it on and off. Any power tool that cannot be controlled with the switch is dangerous and must be repaired.
• Disconnect the plug from the power source and/or the battery pack from the power tool before making any adjustments, changing accessories, or storing power tools. Such preventive safety measures reduce the risk of starting the power tool accidentally.
• Store idle power tools out of the reach of children and do not allow persons unfamiliar with the power tool or these instructions to operate the power tool. Power tools are dangerous in the hands of untrained users.
• Maintain power tools. Check for misalignment or binding of moving parts, breakage of parts, and any other condition that may affect the power tool’s operation. If damaged, have the power tool repaired before use. Many accidents are caused by poorly maintained power tools.
• Keep cutting tools sharp and clean. Properly maintained cutting tools with sharp cutting edges are less likely to bind and are easier to control.
• Use the power tool, accessories, and tool bits, etc., in accordance with the provided instructions, taking into account the working conditions and the work to be performed. Using the power tool for operations different from those intended could result in a hazardous situation.

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What are the service guidelines?

• Have the power tool serviced by a qualified repair person using only identical replacement parts. This will ensure that the safety of the power tool is maintained.
• Follow instructions for lubricating and changing accessories.
• Keep handles dry, clean, and free from oil and grease.

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What are the chain saw safety warnings?

• Keep all parts of the body away from the saw chain when the chain saw is operating. Before starting the chain saw, make sure the saw chain is not contacting anything. A moment of inattention while operating chain saws may cause entanglement of clothing or body with the saw chain.
• Always hold the chain saw with the right hand on the rear handle and the left hand on the front handle. Holding the chain saw with a reversed hand configuration increases the risk of personal injury and should never be done.
• Hold the power tool by insulated gripping surfaces only because the saw chain may contact hidden wiring or its own cord. Saw chains contacting a “live” wire may make exposed metal parts of the power tool “live” and could give the operator an electric shock.
• Wear safety glasses and hearing protection. Further protective equipment for the head, hands, legs, and feet is recommended. Adequate protective clothing will reduce personal injury by flying debris or accidental contact with the saw chain.
• Do not operate a chain saw in a tree. Operating a chain saw while up in a tree may result in personal injury.
• Always keep proper footing and operate the chain saw only when standing on a fixed, secure, and level surface. Slippery or unstable surfaces such as ladders may cause a loss of balance or control of the chain saw.
• When cutting a limb that is under tension, be alert for spring back. When the tension in the wood fibers is released, the spring-loaded limb may strike the operator and/or throw the chain saw out of control.
• Use extreme caution when cutting brush and saplings. The slender material may catch the saw chain and be whipped toward you or pull you off balance.
• Carry the chain saw by the front handle with the chain saw switched off and away from your body. When transporting or storing the chain saw, always fit the guide bar cover. Proper handling of the chain saw will reduce the likelihood of accidental contact with the moving saw chain.
• Follow instructions for lubricating, chain tensioning, and changing accessories. Improperly tensioned or lubricated chains may either break or increase the chance for kickback.
• Keep handles dry, clean, and free from oil and grease. Greasy, oily handles are slippery, causing loss of control.
• Cut wood only. Do not use the chain saw for purposes not intended. For example, do not use the chain saw for cutting plastic, masonry, or non-wood building materials. Using the chain saw for operations different than intended could result in a hazardous situation.

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What is kickback and how can it be prevented?

Kickback may occur when the nose or tip of the guide bar touches an object, or when the wood closes in and pinches the saw chain in the cut. Tip contact in some cases may cause a sudden reverse reaction, kicking the guide bar up and back towards the operator. Pinching the saw chain along the top of the guide bar may push the guide bar rapidly back towards the operator.

Either of these reactions may cause a loss of control of the saw, which could result in serious personal injury. Do not rely exclusively upon the safety devices built into the saw. As a chain saw user, take several steps to keep cutting jobs free from accident or injury. Kickback is the result of tool misuse and/or incorrect operating procedures or conditions and can be avoided by taking proper precautions.

To prevent kickback:

• Maintain a firm grip, with thumbs and fingers encircling the chain saw handles, with both hands on the saw, and position the body and arm to allow resistance to kickback forces. Kickback forces can be controlled by the operator if proper precautions are taken. Do not let go of the chain saw.
• Do not overreach and do not cut above shoulder height. This helps prevent unintended tip contact and enables better control of the chain saw in unexpected situations.
• Only use replacement bars and chains specified by the manufacturer. Incorrect replacement bars and chains may cause chain breakage and/or kickback.
• Follow the manufacturer’s sharpening and maintenance instructions for the saw chain. Decreasing the depth gauge height can lead to increased kickback.

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What are some additional safety rules to follow?

• Read the instruction manual to familiarize yourself with the operation of the chain saw.
• Before using the chain saw for the first time, arrange to have instruction in its operation. If this is not possible, at least practice cutting round timber on a trestle before beginning work.
• The chain saw must not be used by children or young persons under 18 years of age. Young persons over 16 years of age may be exempted from this restriction if they are undergoing training under the supervision of an expert.
• Working with the chain saw requires a high level of concentration. Do not work with the saw if you are not feeling fit and well. Carry out all work calmly and carefully.
• Never work under the influence of alcohol, drugs, or medication.

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What is considered proper use of the chain saw?

• The chain saw is intended solely for cutting wood. Do not use it, for example, to cut plastic or porous concrete.
• Only use the chain saw for operations described in the instruction manual. Do not, for example, use it to trim hedges or for similar purposes.
• The chain saw must not be used for forestry work, i.e., for felling and limbing standing timber. The chain saw cable does not provide the operator with the mobility and safety required for such work.
• The chain saw is not intended for commercial use.
• Do not overload the chain saw.

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What personal protective equipment is required during operation?

• Clothing must be close-fitting but must not obstruct mobility.
• Wear the following protective clothing during work:
  • A tested safety helmet if a hazard is presented by falling branches or similar.
  • A face mask or goggles.
  • Suitable ear protection (ear muffs, custom or moldable ear plugs).
  • Firm leather safety gloves.
  • Long trousers manufactured from strong fabric.
  • Protective dungarees of cut-resistant fabric.
  • Safety shoes or boots with non-slip soles, steel toes, and cut-resistant fabric lining.
  • A breathing mask when carrying out work which produces dust (e.g., sawing dry wood).

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What are the protection measures against electric shock?

• The chain saw must not be used in wet weather or damp environments, as the electric motor is not waterproof.
• Only plug the saw into sockets in tested electrical circuits. Check that the system voltage matches that on the rating plate. Ensure that a 16 A line fuse is fitted. Saws used in the open air must be connected to a residual current-operated circuit-breaker with an operating current no higher than 30 mA.
• Should the connecting cable be damaged, withdraw the mains plug immediately.

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What are some safe working practices to follow?

• Before starting work, check that the chain saw is in proper working order and that its condition complies with the safety regulations. Check in particular that:
  • The chain brake is working properly.
  • The run-down brake is working properly.
  • The bar and the sprocket cover are fitted correctly.
  • The chain has been sharpened and tensioned in accordance with the regulations.
  • The mains cable and mains plug are undamaged.
• Always ensure that the extension cable used is of adequate cross-section. When using a cable reel, wind the cable completely off the reel. When using the saw in the open air, ensure that the cable employed is intended for open-air use and is rated accordingly.
• Keep the cord away from the cutting area and position the cord so that it will not be caught on branches, and the like, during cutting.
• Do not operate the chain saw in the vicinity of flammable dust or gases, as the motor generates sparks and presents a risk of explosion.
• Work only on firm ground and with a good footing. Pay particular attention to obstacles (e.g., the cable) in the working area. Take particular care where moisture, ice, snow, freshly cut wood, or bark may make surfaces slippery. Do not stand on ladders or trees when using the saw.
• Take particular care when working on sloping ground; rolling trunks and branches pose a potential hazard.
• Never cut above shoulder height.
• Hold the chain saw with both hands when switching it on and using it. Hold the rear handle with your right hand and the front handle with your left. Hold the handles firmly with your thumbs. The bar and the chain must not be in contact with any objects when the saw is switched on.
• Clean the area to be cut of foreign objects such as sand, stones, nails, wire, etc. Foreign objects damage the bar and chain and can lead to dangerous kickback.
• Take particular care when cutting in the vicinity of wire fences. Do not cut into the fence, as the saw may kick back.
• Do not cut into the ground.
• Cut pieces of wood singly, not in bunches or stacks.
• Avoid using the saw to cut thin branches and roots, as these can become entangled in the chain saw. Loss of balance presents a hazard.
• Use a secure support (trestle) when cutting sawn timber.
• Do not use the chain saw to prise off or brush away pieces of wood and other objects.
• Guide the chain saw such that no part of your body is within the extended path of the saw chain.
• When moving around between sawing operations, apply the chain brake in order to prevent the chain from being operated unintentionally. Hold the chain saw by the front handle when carrying it, and do not keep your finger on the switch.
• Withdraw the mains plug when taking breaks or leaving the chain saw unattended. Leave the chain saw where it cannot present a hazard.

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What should you do to avoid kickback?

• Never begin the cut with the tip of the bar.
• Never use the tip of the bar for cutting. Take particular care when resuming cuts which have already been started.
• Start the cut with the chain running.
• Always sharpen the chain correctly. In particular, set the depth gauge to the correct height.
• Never saw through several branches at a time.
• When limbing, take care to prevent the bar from coming into contact with other branches.
• When bucking, keep clear of adjacent trunks. Always observe the bar tip.
• Use a trestle.

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What safety features does this chain saw have?

• Chain brake: Brings the saw chain to a standstill within a fraction of a second. It is activated when the hand guard is pushed forwards. The saw chain then stops within 0.15 s, and the power supply to the motor is interrupted.
• Run-down brake: Brings the saw chain to an immediate stop when the ON/OFF switch is released. This prevents the saw chain from running on when switched off, and thus presenting a hazard.
• Front and rear hand guards: Protect the user against injury from pieces of wood which may be thrown backward, or a broken saw chain.
• Trigger lockout: Prevents the chain saw from being switched on accidentally.
• Chain catcher: Protects the user against injury should the chain jump or break.

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How should the chain saw be transported and stored?

• When the chain saw is not in use or is being transported, withdraw the mains plug and fit the guide bar cover supplied with the saw. Never carry or transport the saw with the saw chain running.
• Carry the chain saw by the front handle only, with the bar pointing backwards.
• Keep the chain saw in a secure, dry, and locked room out of the reach of children. Do not store the chain saw outdoors.

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What maintenance is required?

• Withdraw the plug from the socket before carrying out any adjustments or maintenance.
• Check the power cable regularly for damage to the insulation.
• Clean the chain saw regularly.
• Have any damage to the plastic housing repaired properly and immediately.
• Do not use the saw if the switch trigger is not working properly. Have it properly repaired.
• Under no circumstances should any modifications be made to the chain saw. Your safety is at risk.
• Do not carry out maintenance or repair work other than that described in the instruction manual. Any other work must be carried out by authorized service centers.
• Only use genuine replacement parts and accessories intended for your model of saw. The use of other parts increases the risk of accident.
• The manufacturer accepts no responsibility for accidents or damage should non-approved bars, saw chains, or other replacement parts or accessories be used.

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What first aid measures should be taken?

• Do not work alone. Always work within shouting distance of a second person.
• Always keep a first-aid box to hand. Replace any items taken from it immediately.
• Should you request assistance in the event of an accident, state the following:
  • Where did the accident happen?
  • What happened?
  • How many persons are injured?
  • What injuries do they have?
  • Who is reporting the accident?

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What are the parts of the chain saw?

The chain saw consists of the following parts:

1. Cord hook
2. Rear handle
3. Switch trigger
4. Oil filler cap
5. Front handle
6. Front hand guard
7. Guide bar
8. Saw chain
9. Lever (for lever models)
10. Adjusting screw/dial
11. Oil level sight
12. Rear hand guard
13. Lock-off button
14. Chain catcher
15. Guide bar cover
16. Adjusting screw for oil pump (at the bottom)
17. Sprocket cover
18. Spike bumper

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How do you remove or install the sprocket cover?

To remove the sprocket cover:

1. For nut models: Loosen the nut.
2. For lever models: Press and fully open the lever until it stops. Turn the lever counterclockwise.

To install the sprocket cover: Perform the above steps in reverse.

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How do you remove or install the saw chain?

To remove the saw chain:

1. Loosen the sprocket cover.
2. For nut models: Turn the chain adjusting screw counterclockwise to release the saw chain tension. For lever models: Turn the adjusting dial to “-” direction to loosen the saw chain tension.
3. Remove the sprocket cover.
4. Remove the saw chain and guide bar from the chain saw.

To install the saw chain:

1. Make sure of the direction of the chain. The arrow mark on the chain shows the direction of the chain.
2. Fit in one end of the saw chain on the top of the guide bar and the other end of it around the sprocket.
3. Place the guide bar on the chain saw.
4. Align the tension slide with the hole of the guide bar.
5. Holding the guide bar, turn the chain adjusting screw/dial to adjust the saw chain tension.
6. Place the sprocket cover so that the hooks fit alongside the holes and the pin fits its counterpart on the sprocket cover.
7. Tighten the sprocket cover.

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How do you adjust the saw chain tension?

1. Loosen the sprocket cover lightly.
2. Keep lifting up the guide bar tip slightly to keep the guide bar horizontal.
3. Turn the adjusting screw/dial to adjust the saw chain tension.
4. Grasp the saw chain in the middle of the guide bar and lift up. The gap between the guide bar and the tie strap of the saw chain should be approximately 2 – 4 mm.
5. After adjusting the chain tension, tighten the sprocket cover.

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How do you engage an extension cord?

When engaging the extension cord, secure it to the chain saw’s cord with the cord hook. Attach the cord hook about 100 – 200 mm from the extension cord connector. This helps prevent unintentional disconnection.

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How does the switch action work?

To prevent the switch trigger from being accidentally pulled, a lock-off button is provided. To start the tool, depress the lock-off button and pull the switch trigger. Release the switch trigger to stop.

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How do you lubricate the saw chain?

Lubricate the saw chain and bar using biologically degradable saw chain oil with an adhesion agent. The adhesion agent in the saw chain oil prevents the oil from being thrown off the saw excessively quickly. Mineral oils must not be used, as they are harmful to the environment.

To fill the oil:

1. Clean the area around the oil filler cap thoroughly to prevent any dirt from entering the oil tank.
2. Unscrew the oil filler cap and add oil up to the lower edge of the filler neck.
3. Screw the oil filler cap firmly back in place.
4. Wipe away any spilt chain oil carefully.

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What checks should be performed before starting work?

• Checking the chain tension
• Checking the switch action
• Checking the chain brake
• Checking the run-down brake
• Checking the chain oiler

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How do you check the chain tension?

The saw chain is correctly tensioned when it is in contact with the underside of the bar and can be raised approximately 2 – 4 mm from the bar by light finger pressure. Check the chain tension frequently, as new chains are subject to elongation. If the chain is too loose, refer to the section titled “Adjusting saw chain tension” and adjust the saw chain tension again.

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How do you check the switch action?

Before plugging in the tool, always check to see that the switch trigger actuates properly and returns to the “OFF” position when released. To prevent the switch trigger from being accidentally pulled, a lock-off button is provided. To start the tool, depress the lock-off button and pull the switch trigger. Release the switch trigger to stop. Do not pull the switch trigger hard without depressing the lock-off button as this may cause switch breakage.

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How do you check the chain brake?

1. Hold the chain saw with both hands when switching it on. Hold the rear handle with your right hand, and the front handle with your left. Make sure that the bar and the chain do not contact any object.
2. First, press the lock-off button, then the switch trigger. The saw chain starts immediately.
3. Press the front hand guard forwards using the back of your hand. Make sure that the saw chain comes to an immediate standstill.

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How do you check the run-down brake?

Switch on the chain saw. Release the switch trigger completely. Make sure the saw chain comes to a standstill within a second.

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How do you check the chain oiler?

Before starting work, check the oil level in the tank and the oil delivery. The oil level can be seen in the oil level sight.

Check the oil delivery as follows: Start the chain saw. With the saw running, hold the saw chain approximately 15 cm above a tree trunk or the ground. If lubrication is adequate, the oil spray will produce a light oil trace. Observe the wind direction and do not expose yourself to the oil spray unnecessarily.

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How do you adjust the chain lubrication?

You can adjust the oil pump feed rate with the adjusting screw.

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How do you perform bucking cuts?

For bucking cuts, rest the spike bumper on the wood to be cut. With the saw chain running, saw into the wood, using the rear handle to raise the saw and the front one to guide it. Use the spike bumper as a pivot. Continue the cut by applying slight pressure to the front handle, easing the saw back slightly. Move the spike bumper further down the timber and raise the front handle again. When making several cuts, switch the chain saw off between cuts.

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How should wood under tension be cut?

Cut wood under tension on the pressure side first. Then make the final cut on the tension side. This prevents the bar from becoming trapped.

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How do you perform limbing?

When limbing, support the chain saw on the trunk if possible. Do not cut with the tip of the bar, as this presents a risk of kickback. Pay particular attention to branches under tension. Do not cut unsupported branches from below. Do not stand on the felled trunk when limbing.

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How do you perform burrowing and parallel-to-grain cuts?

Perform parallel-to-grain cuts at as shallow an angle as possible. Carry out the cut as carefully as possible, as the spike bumper cannot be used.

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How do you fell a tree?

• Before starting felling work, ensure that:
  • Only persons involved in the felling operation are in the vicinity.
  • Any person involved has an unhindered path of retreat through a range of approximately 45° either side of the felling axis. Consider the additional risk of tripping over electrical cables.
  • The base of the trunk is free of foreign objects, roots, and ranches.
  • No persons or objects are present over a distance of 2 1/2 tree lengths in the direction in which the tree will fall.
• Consider the following with respect to each tree:
  • Direction of lean.
  • Loose or dry branches.
  • Height of the tree.
  • Natural overhang.
  • Whether or not the tree is rotten.
• Consider the wind speed and direction. Do not carry out felling work if the wind is gusting strongly.
• Trimming of root swellings: Begin with the largest swellings. Make the vertical cut first, then the horizontal cut.
• Cut a scarf: The scarf determines the direction in which the tree will fall and guides it. It is made on the side towards which the tree is to fall. Cut the scarf as close to the ground as possible. First, make the horizontal cut to a depth of 1/5 -1/3 of the trunk diameter. Do not make the scarf too large. Then make the diagonal cut.
• Cut any corrections to the scarf across its entire width.
• Make the back cut a little higher than the base cut of the scarf. The back cut must be exactly horizontal. Leave approximately 1/10 of the trunk diameter between the back cut and the scarf. The wood fibers in the uncut trunk portion act as a hinge. Do not cut right through the fibers under any circumstances, as the tree will otherwise fall unchecked. Insert wedges into the back cut in time.
• Only plastic or aluminum wedges may be used to keep the back cut open. The use of iron wedges is prohibited.
• Stand to the side of the falling tree. Keep an area clear to the rear of the falling tree up to an angle of 45° either side of the tree axis. Pay attention to falling branches.
• An escape path should be planned and cleared as necessary before cuts are started. The escape path should extend back and diagonally to the rear of the expected line of fall.

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What maintenance should be performed on the chain saw?

• Cleaning the chain saw
• Checking the plastic housing
• Sharpening the saw chain
• Cleaning the guide bar and lubricating the return sprocket
• Cleaning the oil guide
• New saw chains
• Maintaining the chain and run-down brakes
• Replacing carbon brushes
• Storing tool

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How do you clean the chain saw?

Clean the saw regularly with a clean rag. The handles, in particular, must be kept free of oil.

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How do you check the plastic housing?

Carry out regular visual inspections of all parts of the housing. If any parts are damaged, have them repaired immediately and properly in authorized service centers.

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When should the saw chain be sharpened?

Sharpen the saw chain when:

• Mealy sawdust is produced when damp wood is cut.
• The chain penetrates the wood with difficulty, even when heavy pressure is applied.
• The cutting edge is obviously damaged.
• The saw pulls to the left or right in the wood. The reason for this behavior is uneven sharpening of the saw chain or damage to one side only.

Sharpen the saw chain frequently, but remove only a little material each time. Two or three strokes with a file are usually sufficient for routine resharpening. When the saw chain has been resharpened several times, have it sharpened in an authorized service center.

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What are the sharpening criteria for the saw chain?

• All cutter lengths must be equal. Cutters of differing lengths prevent the chain from running smoothly and may cause the chain to break.
• Do not sharpen the chain once a minimum cutter length of 3 mm has been reached. A new chain must then be fitted.
• The chip thickness is determined by the distance between the depth gauge (round nose) and the cutting edge.
• The best cutting results are obtained with the following distance between the cutting edge and depth gauge:

Chain blade 91PX: 0.65 mm

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What is the risk if the distance between the cutting edge and depth gauge is excessive?

An excessive distance increases the risk of kick-back.

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What is the correct sharpening angle?

The sharpening angle of 30° must be the same on all cutters. Differences in angle cause the chain to run roughly and unevenly, accelerate wear, and lead to chain breaks.