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October 08, 2016 23:16

How to choose a chainsaw

Any host country house certainly have to deal with the need to conduct operations to sawing wood.This is especially in demand during construction or repair work, which the private home ownership is usually always.If there is a furnace, the constant need for fuel resupply.In addition to all - for the houses adjoining the site care: regular pruning of trees cut down or full of old, unwanted, trimming shrubs and hedges, etc.Even leisure activities often requires treatment to the saw - when it is necessary to procure fuel for barbecue or summer-grill oven.

How to choose a chainsaw

chainsaw How to choose

Use the "antiquated" approach with conventional and two-handed saws, ax, secateurs - it is quite possible, but it takes a lot of time, which is usually not enough, and requires a lot of physical effort.Well, that in our time there is an opportunity to buy a modern mechanized tool that greatly simplifies the implementation of time-consuming operations.Thus, the great demand for chainsaws, due to the convenience of working wi

th them and the full autonomy - independence from the presence of the power source.But the tool really met the expectations of the owner, be sure to understand how to choose the right chainsaw, what you should pay special attention to when buying.

Experienced users who are already using chainsaws in their daily work, probably know the basic selection criteria.But for those who are going for the first time to buy this useful "helper" to get started is at least a little to understand the device chain saws - in order to make it clear what is in question when evaluating the characteristics of the instrument.

How does the chain saw

Article Contents

  • 1 How does the chain saw
    • 1.1 Video: Design and Function chainsaw
  • 2 What is evaluated when choosing a chainsaw?
    • 2.1 Planned purpose tool
    • 2.2 types and parameters of tires and saw chains
    • 2.3 rank usability with a chainsaw
    • 2.4 Which brand to choose?
      • 2.4.1 Video: carefully, Chinese fakes chainsaws STIHL

assortment of chain saws - is very wide, as they are used in various fields.

  • This - an indispensable tool in companies involved in industrial timber harvesting and forest farms, conducting regular work cleaning arrays of dead wood or unnecessary shoots.
Without chainsaws impossible industrial logging

chainsaws impossible without industrial logging

  • In construction chainsaw used in the preparation of the wooden parts of constructed structures, cutting through windows and doorways in the log cabins of logs or timber, the sample required slots or spikes, and many other operations.
Indispensable chain saw for construction work

indispensable chain saw for construction work

  • About a variety of domestic, commercial use of chainsaws mentioned above - it is an indispensable tool of good landlord.
  • Moreover, in the capable hands of a master chainsaw becomes a tool for the creation of works of art - a log or decks are converted into unique garden wooden sculptures.
Located in such saws and similar non-standard applications

located such saws and similar non-standard use of

But in spite of such a wide range of uses, all chain saws have approximately the same structure and operate on the same principle.

first consider the chainsaw outside:

The main external components and elements of the chainsaw

main external components and elements chainsaw

All main blade design closed plastic or metal housing (item 1.).Inside is placed powertrain (engine) and to ensure its launch and operation of components and mechanisms.At the top of the housing has a removable cover (Pos. 2), which when removed allows access to the system power supply and the ignition.

Any Saw has two operating handles.Front - in an arc encircling the top housing (pos 3.) And rear (4 pos.), Located on it controls.

In front of the chainsaw mounted rail (pos. 5), with a stretched on it saw chain (Pos. 6).

To start the power unit used manual starter handle is located on the left side of the body (Pos. 7).For pre-swap of fuel to the carburetor on most models there is a special hand pump button (pos. 8).In most cases it is labeled "Rrimer" pointer.

directly around the rear of the handle, so that you can easily reach with your finger is on and switch off the engine ignition system (pos. 9).

On the left side of the body, there are always two fillers - for refueling the saw (pos. 10) and to fill the tank of the chain lubrication system and the tires (11 pos.).Openings are closed tight stoppers.Location necks may differ from the example below, but there are always signs or icons, clearly indicating the purpose of filling the tank.

Control of engine rotation is carried throttle button (pos. 12) located on the rear of the saw handle.Top Handle sure there is another key - lock (pos. 13), which is impossible without pressing the transfer of control to the throttle.This - one of lines in the security.

Before foregrip always placed a special protective sheet (pos. 14), which is cinematically connected to the emergency brake circuit.

View from the retention mechanism saw sets

View from

retention mechanism saw sets the opposite side of the chainsaw is placed a metal or plastic casing (pos. 15) that closes the rotation transmission unit from the engine to the drive sprocket chain.It is also the mechanism of chain tensioner, its lubrication, as well as two mounting nuts (pos. 16) securing the fixed position of the tire.

internal combustion engine used in chainsaws - single-cylinder, two-stroke.Its dimensions, respectively - cylinder diameter and its volume is directly dependent on the power and determine the appointment of the instrument.

Two-stroke engine chainsaw

two-stroke chainsaw

Two-stroke engines do not require a dedicated lubrication system.For normal operation of the application is sufficient mechanisms correctly selected the gasoline-oil mixture as fuel.Gasoline component is burned in the cylinder, and oil - provides lubrication of friction units.

Engine cooling - air.For greater efficiency of heat transfer fins provided an external cylinder body (Pos. 1) and the flywheel has a peculiar configuration of the turbine blades (Pos. 5), which provide a powerful forced air flow.

Inflammation working fuel mixture in the cylinder is carried out candle (Pos. 2).Fuel supply from the carburetor to the cylinder - through a special connecting pipe (3 pos.).Be sure to have a muffler (pos. 4), which reduces the noise of the work unit and directing the exhaust side.

any gear with the change in the number of revolutions of the engine to the drive sprocket is not provided - speed is regulated only by the throttle.But the clutch has (5 Pos.) - Torque transmission is carried out only when it reaches a certain speed level.

The operating principle of a centrifugal clutch mechanism

operating principle of a centrifugal clutch mechanism

This mechanism works on a centrifugal principle.Clutch shoes (their number can vary in different models) pulled towards the center of the spring (pos. 2).coupler force is calculated so that at idling pads are not in contact with the inner surface of the drum (Pos. 3) which is rigidly connected to the drive sprocket chain (pos. 4), and the rotation of the motor shaft (pos. 1) is then transmitted.

The principal device is transmitting torque to the node chain saws

principal device transmitting torque to the node chain saws

By increasing the number of revolutions of the massive block, overcoming the resistance of the spring under the effect of centrifugal force pressed against the inner surface of the drum, and the torque is transmitted to the chain.

tire chain has a slot for inserting the saw studs (key 6.) And the center hole plug (pin), whose position can be changed with a special screw (item 5). - Carried out so the chain tension adjustment.

Many models of chainsaws in the same area is a toothed chain catcher (pos. 7).In the case of chain breakage or formation flying it should not prevent injury to the worker's hands.

This also withdrawn through the screw pump and the oil supply passage from the reservoir for lubricating the chain and gears tires.Many models are equipped with an adjusting screw, by which the flow rate can be changed.

outer surface of the drum (. Item 3) plays another function - it is part of the emergency chain brake mechanism.

The device drum emergency brake

device emergency brake drum

When assembling the drum unit is surrounded by a spring-loaded ring of steel band (Pos. 1).In this inoperative position the saw belt is pressed against the drum by a spring.Before using the tool presses the master plate (Pos. 2) back.In this position, the belt is reduced, and the drum is free to rotate.

Why is this done?Chainsaw - a tool of increased danger and moves the bus circuit is able to cause serious injury.Especially dangerous is the phenomenon of kickback - when the bus drops up or to the side.In the operating state of the saw guard in the rear position is very close to the hand of an employee retention tool for the front handle.In case of a sudden or kickback upwards towards the back of the hand inadvertently move the shield to the forward position, spring loaded belt obozhmet drum and its rotation for 0.5 - 1 second is stopped, and thus stops and the movement of the chain.The engine, however, remains on track.

The chart below shows the screw №3, changing the position of the pin when adjusting the chain tension.

However, the work of the brake requires special care wizard.If you allow the engine speed without moving the panel to the rear operating position, it is easy to overheat the mechanism and even cause melting of the polymer structure with the output of all parts of the mechanism of action.A work without a valid chain brake - is strictly prohibited.

To start the engine - the transfer of the start-up torque, which will supply the fuel mixture from the carburetor to the cylinder and create momentum to spark formation on the candle, use a manual starter.

Recoil starter chainsaw assembly

Recoil starter chainsaw assembly

starter design is simple.This drum with wound on his cable (cord), which ends with a handle located on the outside.The drum itself is located on the frame, having a return spring - it provides a winder rope starter return to its original position.The starter is left most models, coaxially with the engine crankshaft.

With a sharp pulling the cord reel is attached to the small translational movement forward, so that the slots were in response lugs the engine flywheel and the rotational movement transmitted flywheel and then - to the crankshaft.

Service access carburetor and spark plugs made the opening of the top cover chainsaw.

When removing the cover allows access to the spark plug , air filter and carburetor

When removing the cover allows access to the spark plug, air filter and carburetor

Here necessarily arranged filter elements, providing clean air entering the carburetor.They require regular inspection and cleaning - clogged filters are a common cause of unstable operation of the engine or even the impossibility of its launch.

Many models have another external control - adjust the air carburetor (called the "choke" is usually included among the motorists).This adjustment is necessary to facilitate cold start, warm-up before it, especially at low winter temperatures.

Рычаг управления воздушной заслонкой ("подсос")

choke control ( «leak»)

The fuel tank is a filter, providing clean mixture of suspensions.Fuel pumps, as such, no, except for the "primer" for preliminary manual pumping.Pressure equalization tank and the outside (to the formulation of fuel was not created vacuum) provides a special breather on the lid of the tank.During his state also requires regular "look closely" as a clogged breather engine chainsaw will always stall.

layout of specific models of chainsaws, especially - different manufacturers may have some differences.However, the basic scheme for all remains approximately the same.

For greater clarity, the device information chainsaw - demo video clip:

Video: Design and Function chainsaw

What is evaluated when choosing a chainsaw?

Which tool evaluation criteria should be given special attention when buying a chainsaw?

Planned purpose tool

To begin to really represent how much the work will fall on the chainsaw, and with what regularity.From this first selection depends on the desired model.

  • If you need to perform small works with a low frequency, for example, a single billet of wood for the fireplace or barbecue, trimming trees, perform simple operations in the processing of wood blanks, we can restrict the acquisition of an inexpensive model, relating to the classdomestic chainsaws.
Most miniature and light - chain saws consumer class (garden )

most miniature and light - chain saws consumer class (garden)

These instruments are usually designed for very short continuous operation - within 20 ÷ 30 minutes, and a total of not more than 1,5 ÷ 2 hours per day.But even in this mode, it is recommended not to exceed the threshold of 20 hours of use for a month.Lifespan of the unit is small, usually within 400 hours of operation, and to remain a chainsaw "assistant" as long as possible, it requires an appropriate, very rational use.

Power saws household power unit is typically less than 1.5 kW, and the volume of the cylinder - about 40 cm³.Domestic class saws usually have a very efficient muffler that reduces the noise to a minimum the effects of their work.

With all these shortcomings in these chain saws, there are undeniable advantages.This - the compactness and light weight.These qualities allow the use of consumer-class tool for almost everyone, regardless of the level of physical fitness of the person.

  • second class chainsaws - a semi-or, as they are often called - "farmer".
Пример бензопилы полупрофессионального класса ("фермерского")

Example chainsaw semi Class ( "farm»)

This is - quite a serious tool that can withstand a few hours of continuous operation (about 4 hours per day).Power of the power unit reaches 2 ÷ 2,5 kW, cylinder - up to 60 cc.

This chainsaw has quite suitable for any household needs, including - for regular firewood, small trees stall and cut into logs, for a variety of construction operations.Most often, these are the carpenters saws used in the construction of log cabins or log homes.Apply these saws and felling trees, but only for cleaning the trunks and branches of knots.

lifespan laid down in such a chainsaw, usually about 1000 hours.For the "arsenal" of a country house of the owner, constantly living in it, it is likely the best option.

course, and the dimensions and weight of the chainsaw is already significantly higher than that of domestic class tools, and work with it will require a certain preparation.

  • Finally, chainsaws professional class.