In recent decades, the chainsaw has established itself as a replacement for the classic tools used to branch trees and cut down portions of forest, such as the axe or hand saw.
Just at the beginning of the last century saw the light of the first patent of this machine, equipped with an internal combustion engine and intended for cutting very large logs; this tool was definitely not easy to handle, so that to use it was required the intervention of at least a couple of strong people.
Then came the fifties, and Andreas Stihl designed the first chainsaw easy to use even for one person, the famous Stihl BL (one of the largest chainsaw manufacturers, in fact, still bears the name of this inventor). Later on, the company itself started to use the electric saw, pick a pro chainsaw equipped with an electric motor that is particularly suitable for gardening operations.
The same name of this instrument, composed from two parts, makes us guess the number of elements of which it is composed, that we go to describe in brief here below.
Let’s start from the engine; it is internal combustion, it is fed with a particular mixture of oil and gasoline (in the ratio of 2 and 5 percentage points) and it is a two-stroke. To use pure gasoline without mixing it with a right part of oil is strictly forbidden, because it causes damages to the engine, sometimes even not repairable; who uses instruments that instead must be fed with gasoline only is advised to signal with a very clear writing on the different containers their actual content (gasoline or mixture), in order to avoid causing very expensive damages.
Usually the mixture finishes slightly before the oil, being the doses of the mixture calibrated in a particularly careful way in anticipation of regular operation; if the oil should in fact finish before the mixture the chain would overheat, due to the lack of oil that usually reduces friction.
When using the chainsaw after a few months in which it has been idle (for example at the beginning of the season) it would be good practice to carry out targeted checks so that it starts again in a short time. Let’s go on to describe the guide bar; it is a metal support with grooves on the outside, where the cutting chain acts, which in turn is the most important part of the entire tool.
The blade must have the right level of tension, which must be checked carefully especially after it is turned on again after periods of inactivity; to do this simply take it between your thumb and forefinger and pull in the opposite direction to the body of the bar itself.
In case it should create a vacuum of a certain entity it will be necessary to adjust a particular screw, which is usually located in the point where the internal combustion engine and the guide bar join; help yourself with the instructions for possible operations of this type.
The most important thing to check before using a chainsaw is certainly the level of sharpening, which must be very precise; it is inevitable that the smaller blades of the chain will cut less effectively after a few hours of work, so they must be resharpened, in order to give them back the incisiveness on the wood they originally had.
But how do you find the right time to sharpen them? If you want to be on the safe side, do the so-called chip test (i.e. the chip that the blade produces by cutting the wood); if the chips are medium long then you will be cutting well and evenly, this means a correct sharpening of the chain that allows it to sink well into the material; if the chips are instead small, almost reduced to dust, the blades will certainly have to be rolled.
Later on we will also briefly talk about how to sharpen the cutting chain. Then we have another element of the chainsaw, the handle or rather the two handles, one for each hand of those who must use it. The front handle is a kind of support for the whole tool: it consists of an iron tube in the shape of a bow, so curved, and crosses the whole body of the engine.
The chainsaw controls are all located near the point where the base of the second handle is located, that is the rear one; these controls are the air knob to be used only when the engine is still cold, the throttle lever, and finally obviously the start and stop.
It is from this handle that the chainsaw is actually operated, directing it correctly and giving it the exact intensity to cut. Let’s move then to the tanks: they are all equipped with a mark, of tradition located on the caps, so it is really difficult to confuse them (on the caps is in fact usually located the “food” necessary to the chainsaw for proper operation).
The oil to lubricate the cutting chain is one of the fundamental elements; it is not a mineral oil like the others (currently in use for car engines or blends), so every time you decide to buy it take care to communicate to the retailer the model and brand of the chainsaw in your possession.
The instruction booklet will help you for further testing on more technical features and types of tools. In order to easily verify if the cutting chain is well lubricated, make the chain turn on empty at a distance of about ten cm from a wooden element, which is clean and smooth; if the element that distributes the oil automatically works properly then a stain will remain on the wood to indicate the oil that has been splashed out by centrifugal force in action; if the stain should not be there then you must go to a specialized mechanic as soon as possible.
Finally let’s talk about the safety devices: usually they are represented by a plastic plate located next to the handle of the chainsaw (the upper one); pushing this plate you can immediately stop the rotation of the blade in urgent cases.
The types of chainsaw available on the market are various, and differ from each other in the use they are made of. The most common types of chainsaw are those intended for forestry or agricultural use: they are generally elongated in shape and are equipped with a guide bar to slide the chain to cut.
There are different sizes: small displacement for less consistent cuts, for example to be used on garden plants (20-35 cubic cm, power 2 or 2.3 hp); medium size and displacement, to be used on trunks of medium size (displacement of 40-60 cubic cm, power 2.5-4 hp); giant displacement, used especially by those who work in the woods (80-100 cubic cm, power 6-8.5 hp).
The cost varies depending on the levels of power and size, ranging from 200€ indicative for smaller displacements to 500/600€ for larger ones (you must then take into account the variations between a manufacturer brand and the other and between a point of purchase and the other, of course, for further variations in prices); in a special paragraph will be indicated a couple of websites on which you can check the various prices on the market.
But let’s go back to talk about the various types of use: some chainsaws have the cutting bar mounted on extensions, so you can cut the branches of very tall plants or trees such as oak, etc.. To close, we describe a very particular model of chainsaw, which is intended for exceptional uses; for example, we have the chainsaw with a large grinding wheel mounted in the place that would belong to the bar, used by the Fire Department.
We conclude this section with a few quick tips for a conscious purchase of your chainsaw and to avoid “cheating” during this phase: before buying the chainsaw, take a tour of all the stores in your neighborhood so that you can make well-designed comparisons between the various products; ask the dealer as much information as possible about the tool you intend to buy; get advice from acquaintances or friends with experience in the field;
make your choice on prestigious brands and quality (the higher costs will certainly be balanced by a significant savings in repairs and maintenance operations).