Even the popular Stihl does not last forever: the teeth of a chainsaw eventually wear out, which is easy to determine by the nature of the chips that form. With a dull cutting edge, the chips turn out to be small, because the working edge does not cut, but crushes the wood. Naturally, the effort expended by the operator increases sharply. It's time to sharpen the saw. How to do this correctly - choose the optimal technology, determine what angle of tooth sharpening should be and how to check it?
External signs of a dull cutting edge of a chainsaw tooth
Let us recall that a chainsaw tooth has a complex configuration (see Fig. 1), which also depends on the direction of movement of the chain. It has two working edges: a side edge, which is located perpendicular to the axis of movement of the links, and an upper edge, located at a certain angle to the direction of movement of the chain. In addition, a limiter is provided on each tooth, the parameters of which determine the height of the chips removed. Since the main cutting force falls precisely on the working angle, all subsequent work with the tool will depend on the angle to which the tooth is sharpened.
Figure 1 – Functional parts of a chainsaw tooth and their appearance
Before starting long-term work with a chainsaw, it needs to be inspected and test sawed, as a result of which:
- Visually determine the presence (or absence) of a conical section adjacent to the corner of the tooth, as well as a radius rounding on it - the main signs of blunting (see Fig. 2).
Figure 2
- Check the feed force at which the tool operates steadily and produces a quick cut. For sharp teeth, the initial moment of penetration of the tooth into the wood occurs quickly, and without significant resistance to the material.
- Find out the presence of chain vibrations during a steady cut - if they are noticeable, then the teeth need to be sharpened.
- Inspect the appearance of the newly cut end (especially if the tool is used for rip sawing). If there are rough chips and dents, the chainsaw chain must be sharpened.
Sharpening angles and chainsaw tooth configuration
The cutting edge of a tooth is characterized by the following parameters:
- Width;
- Thickness;
- Sharpening angle.
In addition, each tool model has its own tooth pitch, the value of which for household and semi-professional models is associated with the power of the chainsaw and the torque that the drive develops. For example, for rip sawing, the pitch is taken smaller (for example, 0.325 inches). In this case, work productivity will decrease, but the required force will be significantly lower. Upper step values for household chainsaws are adopted extremely rarely, mainly when felling trees with a large trunk diameter. The engine power should not exceed 2500 W.
The thickness of the cutting edge of most chainsaw manufacturers is set to the same, and equal to 1.3 mm (there are also edges with a thickness of 1.1 mm, but, firstly, they are extremely difficult to sharpen at home, and, secondly, such links are extremely have little functionality: they can only be used for cutting thin branches).
The height of the chain profile can be either 0.625 mm or 0.762 mm, and in the vast majority of cases, a low profile is used for household gasoline tools. When sharpening limiters, this parameter is very important, because as the height of the excess permissible values decreases, the vibration of the tool during operation increases, although the quality of the cut remains satisfactory. Therefore, you should not get carried away with reducing the height of the stop when sharpening a tooth.
The sharpening angle of a chainsaw chain depends on the main purpose of the tool - for transverse or longitudinal sawing. Since during longitudinal sawing the resistance of wood is always noticeably higher, the edge of the tooth must be very sharp. It is recommended to do it in the range of 6...12° (for comparison - with a predominance of cross cuts - up to 25...30°). Naturally, in the first case, sharpening should be done more often, and especially carefully, since an unacceptably small angle of inclination of the tooth contributes to its rapid chipping when using a chainsaw. This is especially important for links that are made from structural alloy steels containing silicon and manganese, for example, 40ХГС or 35ХГСА.
Chainsaw chain sharpening template
When purchasing a chainsaw, it is advisable to acquire a special template (see Fig. 3), with which you can easily set the optimal values of the tooth angles. It is used to control the values of the rear angles of the upper and end blades, as well as the front edge angle (it is indicated in the manufacturer’s instructions and can vary within 65...80°).
It is especially important to use a template to estimate the clearance angle of the upper blade. This sharpening angle of a chainsaw chain is otherwise very difficult to determine, and yet it must be maintained within rather limited limits - from 50 to 60°.
The sharpening angle is measured by determining the angle between the top cutting edge and a line perpendicular to the chain guide.
The sharpening angle of the chainsaw chain can be changed depending on what work will be done. As the hardness of the wood increases, its value should decrease. In general it is considered optimal value angle 10...12° - for longitudinal cutting, and 25...30° - for cross cutting.
Figure 3 – Appearance of a template for sharpening chainsaw teeth
Sharpening can be done manually using a round file with a working diameter of 4...5.5 mm, or on a machine. In the first case, it is extremely important to correctly position the tool relative to the tooth being sharpened. The upper edge of the working part of the file is located approximately a fifth above the upper edge of the tooth. The tool is positioned perpendicular to the chain axis, and at an angle of 25...30° to the upper edge of the tooth
One round file is not enough. To sharpen the limiter, you will need a flat file, and to clean the work area, you will need a hook that removes the sawdust that forms. There are also special holders on sale, on which the lines of the direction of movement of the file relative to the chain axis are graduated. As can be seen from Fig. 4, the holder can be installed on the tooth from above, and rest on its upper edge. Since the height of the holder is adapted to a certain chain pitch, it should be selected in relation to chainsaws of specific models and brands.
The minimum required kit to obtain the correct chain sharpening angle manually, shown in Fig. 5.
Figure 5 – Kit sharpening tool and accessories
First, the teeth of one direction are sharpened, and then the other. Start by lightly pressing the tool away from you, gradually increasing the load. During sharpening, the round file is periodically rotated along its axis.
Mechanized sharpening on a machine
Sharpening on a machine is much more convenient and does not require highly qualified performer. Such machines are electrically driven and equipped with special grinding wheels.
For a household workshop, it is worth purchasing compact units that do not take up much storage space and are suitable for quick and high-quality sharpening of chainsaw chains from different manufacturers. Such units should operate from a stationary power supply with a voltage of 220 V, have low power consumption (up to 100 W) and be easy to install on the circuit.
When choosing a machine, you need to pay attention to the following technological characteristics:
- Possibility of processing teeth with different thicknesses of the upper edge and different chain pitches;
- The ability to adjust the sharpening angle, within the limits specified earlier;
- Availability of replacement grinding discs;
- Constant value of the cutting width.
The design of the machine is simple and includes a drive electric motor, a shaft with a seat for a sharpening disk, a handle with controls, and a device for attaching the machine to a chain. Adjustment of the force of pressing on the sharpened element is ensured by a spring clamp. Modern models of sharpening machines are equipped with a differentiated clamp, which provides for self-centering of the product on the machine. For ease of work, there is a measuring scale on the clamp body.
Optionally, the machines can also be equipped with a miniature electric light bulb, which provides illumination working area, as well as a hydraulic booster, making sharpening easier.
Safety of work is ensured by a folding safety shield.
The first chainsaws appeared at the beginning of the twentieth century. The chains installed on them with straight and flat teeth, like modern hacksaws, were characterized by low efficiency, quickly dulled and required very labor-intensive maintenance. For example, when sharpening, it was necessary to take into account that the teeth are divided into trimming, cutting and chipping, have different cutting angles and orientations in relation to the direction of movement (they can be deviated to the left, right or located in the center).
There is no doubt that attempts to modernize the circuits have been made repeatedly, but only one of them was successful. Developed by Joseph Cox and launched in metal in 1947, the new L-shaped universal sawing chain, thanks to its increased productivity and simplified sharpening, very quickly pushed its predecessor out of the market, and now almost all saw chains“flaunt” the characteristic crescent-shaped profile of the cutting links.
Technical parameters of saw chains
Picking up chain for chainsaw, pay attention to such characteristics as its purpose, pitch, thickness of the drive link, profile height and cutting depth.
It is known that sawing wood cutting along the grain is more labor intensive than cutting across it, and to achieve the best results it is advisable to use chains that are suitable for the task at hand.
The main difference between longitudinal and transverse type chains is the angles of attack of the cutting links. For cross-cutting chains, they are 25–35 degrees; for longitudinal sawing chains, the angles are sharper – from 5 to 15 degrees.
The use of chains inappropriate for their purposes can lead to either reduced productivity (if cross-cutting is carried out with a longitudinal chain), or increased “aggressiveness”, strong vibration and additional load on the engine. However, many users prefer not to waste time replacing the chain and longitudinal cuts are made with the same chain as transverse ones, especially if the “quality” of the resulting cut does not require compliance with the “highest” level. Therefore, chains for longitudinal sawing are in demand in smaller quantities, and they are produced in volume , commensurate with demand. It is not surprising that it is much more difficult to buy such a chain than a cross chain. And the issue of purchasing them becomes really relevant if you plan to use special machines like mini-sawmills.
The larger the chain pitch, the larger the links that make it up and the higher its performance.
Chain pitch– the distance between three consecutively located rivets, divided by two. This is a defining parameter, and depending on its value, all existing chains are divided into five groups with pitches of 1/4″, 0.325″, 3/8″, 0.404″ and 3/4″.
Step 1/4″(6.35 mm) is inherent in miniature chains installed on low-power one-handed saws. True, in Russia they are practically not used.
Chains with steps 0.325″(8.25 mm) and 3/8″(9.3 mm) - the most common options. More than 80% of saws produced around the world are equipped with them.
Steps 0.404″(10.26 mm) and 3/4″(19.05 mm) are distinguished by chains with larger links and increased productivity. For several decades, they were equipped with Russian-made saws, but now they are installed only on powerful felling saws and harvesting equipment.
Pitch is traditionally measured in inches, and is written as follows: three digits are ordinary, and two digits are decimal fractions. This is necessary to avoid confusion. In particular, the result of converting 3/8″ to decimal is 0.375″ - the difference with the previous standard (0.325″) is just one digit.
The larger the chain pitch, the larger the links that make it up and the higher its performance. But, on the other hand, the wider the cut, and more is required to overcome the cutting resistance. powerful saw. Small pitch chains have other advantages - a larger number of teeth per unit length, smooth movement in the cut and, accordingly, reduced vibration. And their cuts turn out cleaner.
Drive link thickness(shank) is the second most important parameter. During operation, the chain slides in the groove of the bar, and this sliding should be smooth, without snagging and at the same time without unnecessary “bumpiness”. In a word, the thickness of the shank and the thickness of the groove must strictly correspond to each other, increasing the reliability of the chain fit and eliminating the likelihood of it “jumping off”. The international community of manufacturers provides five standard sizes, measured in inches or millimeters (whichever is more convenient): 1.1 mm (0.043″), 1.3 mm (0.050″), 1.5 mm (0.058″), 1.6 mm (0.063″) and 2.0 mm (0.080″).
1.1 mm– such thin drive links are typical for the smallest chains and saws of the appropriate size.
1.3 mm– perhaps the most popular size, typical for household and semi-professional chains.
1.5 mm– ranks second in demand. Installed on more powerful and productive saws.
1.6 mm And 2.0 mm– such thick shanks are found only on chains for highly professional saws.
Profile height. Saw chains are available in high or low profile depending on the height of the cutting edge above the plane of the guide bar. The former are used for professional purposes to achieve maximum productivity. The latter are installed on amateur-class chainsaws, since due to the increased support area of the cutting links and the reduced thickness of the cut chips, they are safer.
Depth of cut - the size of the gap between the upper edge of the tooth and the cut stop, which regulates the thickness of the chips. Most often, there are samples with gaps of 0.025″ (0.635 mm) and 0.030″ (0.762 mm), less often – with gaps up to 0.070″ (1.778 mm), but they are intended for machine felling units.
The depth of cut largely determines the performance of the chain and its sawing speed. The larger the gap, the higher the performance. But in the pursuit of efficiency, one should not forget about vibration: chains with a small depth of cut in the cut move softer, “twitch” less. Therefore, manufacturers, trying to balance vibration and performance, very often install cutters with a minimum depth of cut on chains with a large pitch, and vice versa .
Engine size. This parameter characterizes the saw and, it would seem, has nothing to do with the chain itself. However, catalogs and brief annotations for chains often list the engine sizes they are designed to work with. And these recommendations should be followed. A chain installed on an engine that is too powerful for it will experience heavy loads and fail ahead of time, never having reached its service life. Variations in the load on the motor and other important components of the saw itself.
Chain components
Any saw chain consists of three types of links: cutting, driving (shanks) and connecting. The strength of the connection is ensured by rivets.
Cutting link- perhaps the most complex part of the saw chain, actually consisting of two parts: a cut depth limiter and a cutting element with an L-shaped contour cutting angle.
The upper cutting edge of the link is always wider than the chain and bar itself, due to which the cut is quite free and the cutting resistance is minimal. The tooth works on the principle of a plane: the further the knife (upper cutting edge) is extended above the plane of the plane (cutting limiter), the thicker the chips.
The performance characteristics of the cutting link are determined by numerous factors, namely: the sharpening angle of the top edge and its working, cutting angle, the angle of the side edge (angle of attack) and the height of the cutting stop. During sharpening, the values of all these parameters must be strictly maintained, since even a small change can lead to negative consequences.
The cutting teeth are right-handed and left-handed, and they are strengthened alternately with chains. But in general, cutters are divided into types depending on their profile. Upon careful study of the “shapes” formed by the upper and side edges, two “boundary” options can be distinguished: a “seven” with an acute angle between the edges and a rounded “sickle”. The first option is called chisel (from the English chisel - cutter, chisel), the second - chipper (from the English to chip - chop into chips).
Chisel teeth are characterized by high cutting performance and cutting speed. Due to their configuration, they have a smaller contact area with wood during operation, which reduces cutting resistance. This is a professional option, but it is very sensitive to an abrasive environment, quickly becomes dull when working with “dirty” wood, and when sharpening it requires strict adherence to all angles and parameters.
The crescent-shaped profile - chipper - is less effective, since it has a slightly larger contact area with the wood, but it is also much easier to care for - the rounded corner does not respond so painfully to minor errors during sharpening. Such links are good when working with contaminated wood.
All other profile options are various modifications of the two described above.
Upper and side edge The cutting element is usually coated with a thin film of some hard metal. Most often it is chromium, but sometimes a nickel-phosphorus alloy is used. The coating applied by galvanic method significantly improves the anti-friction properties of parts, increases wear resistance, hardness and, in fact, does all the main work of cutting wood fibers. The steel “core” serves as a substrate or base for the coating.
Leading links(shanks) ensure the movement of the chain, transmitting rotation from the engine through the drive sprocket, as well as a stable position of the chain on the saw bar. In this case, the chain moves through a special groove provided in the design of the guide bar. A “side” responsibility of the drive link is to distribute lubricant from the drive sprocket (where the oil pump supplies it) throughout the bar and chain. It should be noted that the number of shanks plays a major role in designating the chain length for a certain length of the saw bar, which makes it easier right choice and size compliance.
Connecting links, true to their name, they combine the cutting and driving parts into a single whole, called a saw chain.
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Technological improvements
Developed by Joseph Cox, the cutting link concept has changed little over the years. Of course, they tried to modernize it, but all the improvements made concerned either the lubrication system or the fight against vibration and kickback.
Lubrication system. Chain and bar lubrication is a very important factor. The design of chain saws includes a pump that supplies oil from the tank to the cutting system through special holes. But then the chain itself distributes it. The shanks, passing the sprocket, “capture” the lubricant and “spread” it throughout the tire and chain. Bottom part This is why they are designed in the form of a hook - so that they “grab” more and “lose” less. To additionally retain the lubricant, special holes are drilled in the shanks or channels are milled. The lubrication system often uses connecting links - additional recesses are made in them for lubrication.
Abundant lubrication reduces friction and heat, thereby not only increasing the service life of each element, but also reducing chain stretch. So constant control over the lubrication process is in the interests of each user. It is carried out quite simply: when accelerating the chain, microscopic drops of oil (if it is supplied in sufficient quantity) form an oil trace in the form of a strip on any light surface (for example, on a tree trunk that is about to be sawed), if bring the end of the tire to it. No trace - alarm signal, indicating a lack of lubrication and requiring an immediate solution to the problem (checking for oil, cleaning the tire groove, adjusting the pump, etc.). And one more thing: modern chainsaws allow the installation of chains and bars of various lengths, but before using a new headset, you need to make sure that the oil pump can handle its “processing”.
To improve the lubrication process, many manufacturers in Russia offer special oils. They are made on a plant basis (for example, rapeseed) using polymer additives that self-neutralize within two hours upon contact with plants and soil. In addition to the environmental benefits, the lubricating properties of these oils are 30% higher than those of automobile oils. And their consumption is approximately 25% less.
Combat vibration and kickback.Vibration is dangerous because as a result of its prolonged exposure (as happens, for example, among professional fellers), the so-called Raynaud's symptom can develop: as a result of deterioration in blood supply, the fingertips lose their sensitivity and react painfully to temperature changes.
The desire of manufacturers to reduce the harmful effects of high-frequency vibrations comes down mainly to the development of special shock-absorbing parts. The cause of vibration is the constant collision of the cutting teeth with the wood. At the moment when the cutter hits the wood with its working edge, it stops for a fraction of a second, being clamped between the wood and the guide bar. In this case, part of the shock wave energy is transmitted through the chain and drive sprocket to the operator’s hands. Another part is also communicated through the chain to the guide bar and, again, to the operator’s hands. If you reduce the impact force, the vibration level will also decrease.
The beveled cut stop helps reduce shaking; thanks to it, the chain moves more smoothly, and the wood slides off the cutting tooth more smoothly. Special shock-absorbing protrusions on the driving and connecting links also serve the same purpose.
Another effective way– beveled or raised heel of the cutting link. This design allows the saw chain to sag slightly when the cutting tooth hits the wood, and the link does not immediately hit the bar, and the force of this impact is noticeably reduced. As a result, not only vibration is reduced, but also tire and chain wear.
These structural elements are designed to help with reverse impact - a situation that occurs when the user touches any hard surface with the toe of the tire while the chain is moving (if we draw an analogy with a watch dial - the sector “from 12 to 3 o’clock”). At the same time, the saw rebounds sharply, creating a traumatic moment. The beveled cutting stop and shock-absorbing lugs minimize this effect.
The order of the links
Saw chains are classified based on their dimensions, design features and on the order of the links. It can be standard, with a half pass or skip. In the first case, there are two leading links for each cutter. In the second, every third cutting link is replaced by a connecting link. And finally, in the third case, a connecting link is installed in place of every second cutting link.
It is almost impossible to purchase a ready-made chain with a “non-standard” alternation of links - they are not found in stores. It’s another matter if the chain is riveted independently. An artificially high distance between cutters reduces their number, and, consequently, reduces cost. However, increasing this distance increases vibration, reduces productivity and cutting speed.
Care and maintenance of saw chains
The saw set - that is, the chain, bar and drive sprocket - is consumables, and, naturally, when purchasing, the user is interested in the question: how long will this material last? But there is no exact answer here, since the “shelf life” of the above-mentioned parts largely depends on the type of work that will be performed with their help, on the degree of care for them, etc. Contaminated sawing material and careless handling will significantly reduce the service life. For example, if you touch the ground with the tip of the tire while working, the sharpening quickly “goes away” - sand (i.e., abrasive) in combination with high speed of movement “takes it down” very quickly. A nail in an old log cut for firewood can sometimes destroy even a new chain without any hope of resuscitation. And there is no need to remind that such moments are dangerous not only for the chain and saw, but also for the operator himself.
If all the parts are lubricated on time and efficiently, and the teeth are properly and accurately sharpened, then one tire will be enough for approximately one drive sprocket and three or four chains. Moreover, it is advisable to use the chains alternately: today - one, tomorrow - another, and so on in a circle. Then the tire, sprocket and chains themselves will wear out evenly. If you use only one chain, leaving the others “in reserve”, then when their turn comes, they will work with “slippage”, experiencing additional dynamic shocks when moving, and will fail much faster. And all because the drive sprocket wears out according to the configuration of the shanks of the first chain.
Running in a new chain– a sequence of actions recommended by specialists that ensures a long “working” life. The first step is to soak the chain in oil for several hours. The meaning of the event is obvious: the lubricant has time to flow into all the small cracks and reliably “saturate” the parts and rubbing joints. The second step is to install the chain on the tire and briefly “run” it at idle speed. After stopping the engine, you need to check the tension of the chain and, if necessary, tighten it, after cooling it first. And after this, after making several cuts with minimal pressure on the bar and rechecking the chain tension, proceed directly to work.
Chain tension- Very important point. A chain that is not tensioned enough will dangle and may jump off the tire or even burst. Reupholstering also does not bode well - it causes excessive wear and increased load on the engine. In addition, the design of almost all Piltaks means that tensioning the chain also strengthens the tire - in a “relaxed” state, the tire moves freely left and right. To check, it is enough to take the chain at the top of the bar, approximately in the middle or a little closer to the tip, by the tooth and pull it up. With the correct tension, approximately a third of the shank remains in the bar groove. If more, the chain is overtightened; less, the chain is undertightened. In this case, the chain itself should move freely by hand.
Lubrication. We have already mentioned the need for careful lubrication of the chain. But even if the chain and saw are equipped various systems to improve lubrication, pre-soaking the chain in oil will not harm it, but, on the contrary, will reduce wear caused by friction and provide a longer service life.
Chain sharpening requires compliance with two rules. Firstly, you should control the sharpness of the corners of the cutting link, the height of the cut limiter and the compliance of these parameters with those initially specified at the factory. And, secondly, clearly control the identity of the dimensions of all cutting links of one chain.
What are the consequences of non-compliance with these principles? So, if the angles on all cutting elements are the same, but incorrect, the user risks either reduced performance or increased vibration and load on the engine. At different sharpening angles, due to uneven load on the cutting elements, vibration will increase and the likelihood of chain breakage will increase. In any case, premature failure will be ensured.
That is why all the teeth of the chain must be sharpened evenly and at the same initially specified angles, which, by the way, were established experimentally. Then the chain will last as long as possible and efficiently. This is not a very difficult task; special devices for sharpening the chain allow you to maintain the specified parameters without thinking and without resorting to precise measuring instruments.
Another important point is to monitor the slightest cracks, abrasions and bruises that can lead to a chain break. If the chain breaks during operation, it slips off the tire and flies down at high speed, under the operator’s feet. To avoid accidents, all saws are equipped with a chain catcher in the form of a protrusion. Still, extra attention won't hurt.
Each user will be interested to know that any new chain sealed in a bag is just a stamping, and by sharpening it, you can increase productivity by about a quarter. In addition, with new chains, the height of the cut stop, and in fact the thickness of the resulting chips, is automatically “adjusted” to the minimum value, i.e. for working conditions in “harsh” conditions (winter, frozen and hardwood etc.). And if sawing is carried out in the summer, and its object is freshly cut pine, there is a reason to adjust the limiter (using a special template) to speed up the work.
Chainsaw - necessary tool For household needs, He will find a worthy use in the country. A chainsaw is easy to cut wood for a stove or fireplace. She also performs well when every owner of such an assistant should know correct angle Calling a specialist to your home, and especially to your dacha, costs a lot of money. Therefore, you have to make do on your own.
Although it is better to entrust sharpening to a professional, some lumberjacks have learned this craft on their own. If wood cutting specialists have to sharpen a chain 3-4 times a day, then an ordinary gardener does not have such a need due to the fact that he rarely uses the tool. How can you master the craft yourself? There are some recommendations for this.
Features of the chainsaw
Cutting wood is similar to working with a plane. In this case, the size of the cut depends on the thickness of the limiter. When the saw chain works hard, the teeth become dull faster. This is clearly manifested when the ground surface appears in the path of the chain. To completely dull the teeth, it is enough to “catch” on the ground for a couple of seconds.
If you sharpen it as often as possible, the chain will last much longer, since very little metal will be removed. In addition to the question of what angle of sharpening the chainsaw chain should be, you should also know this!
Working with a dull tool is undesirable for a number of reasons. First of all, this affects the quality of the cut, and not in better side. Fatigue also quickly sets in, which is felt not only in the hands, but also in the body.
Another reason is unjustified excess fuel consumption. All parts will work in increased mode, which inevitably leads to rapid wear. Performance drops seriously, which also happens when using a defective chain.
Features of the chain structure
To effectively be able to sharpen a chainsaw chain, you need to know the structure of its teeth. You can’t do without knowing the sharpening angle. Each tooth has a complex structure. Its geometry is represented by the following components:
- basis;
- spatula;
- depth limiter.
In this case, the blade consists of two blades: the end blade and the top blade. Moreover, between them there must be the correct sharpening angle of the chainsaw chain in order to provide it with the necessary performance.
As you can now guess, it is not the chain that cuts the tree, since it serves as the basis for securing the cutting links and moves them at high speed. The links themselves have sharp blades, with the help of which the wood is cut.
How do you know when sharpening is needed?
You can determine whether the chain teeth are ground down or not by looking at some characteristic features. Of course, it all depends on how intensively the chainsaw is used. It’s worth taking a closer look at what kind of shavings it leaves behind. Its uniformity and square shape indicate sharp teeth. If the chain is worn down, it usually leaves behind wood dust, and the sawdust itself resembles the needles that a hand saw “produces.”
If the cutting speed is reduced, then this is also considered a sign of a dull chain. You can feel an increase in the load on the instrument itself and the appearance of vibration. Beginners may not always be able to spot some of these signs. Therefore, they should pay more attention to the quality of the chips. Sometimes it can be brown, which is a guaranteed indication that it’s time to sharpen the chain.
Sharpening methods
To sharpen a tool, you can turn to the services of craftsmen who not only know what angle of sharpening chainsaw chains is necessary, but also do all the work quickly and at a professional level. As a rule, the cost of such services is not so high, but the quality, on the contrary, is very high! This option is suitable for those who like to cut wood and have no desire to tinker with their tools.
Everyone else will be interested in trying their hand at this. Professionals in this regard always choose automatic equipment, which is characterized by maximum efficiency and accuracy. Of course, not every lumberjack can afford to purchase it, and therefore they manage in different ways. And here, among many amateurs, there are discussions about which technique is better to give preference:
- manual;
- alternative;
- modern.
You should not neglect the signs of dullness, and at the first need, begin the operation of sharpening the chainsaw chain. This will allow you to use it for as long as possible.
Correct sharpening angle values
The angle is not a constant value and does not depend on the manufacturer or model of the equipment. It is selected taking into account what kind of tree you will be dealing with. You can choose some average value, but the cutting efficiency may be ineffective. For this reason, it is necessary to choose the correct value, taking into account the specific type of wood.
If we are talking about solid wood, including those trees that have been “frozen” for a long time, it has a high resistivity. In this regard, the sharpening angle should be reduced. This will practically avoid the occurrence of vibrations, and the movement of the chain will be softer. The minimum value is 25°.
For soft types of wood, the sharpening angle can be increased, but not more than 35°. This will significantly improve productivity. As for the sharpening angle of the chainsaw chain for rip sawing, the value is 10°. In this case, the cut will be as smooth as possible, and equipment vibration will be minimized. Knowing these features, we can proceed to consider different ways sharpening.
Manual method
This is the simplest and slowest method for sharpening chain teeth. However, the method is good when sharpening is done on site in the forest. Why not carry a whole machine with you all the time?! But here it is worth being more precise - this does not mean one tool, but a whole set, which includes:
- flat file;
- round file;
- sample.
Each of them performs their duties. The main purpose of the flat tool is to sharpen the depth gauge.
A round file already performs the main operation, making the cutting edges sharper. In this case, each chain requires a certain tool diameter:
- pitch ¼ inch - 4 mm;
- pitch 0.325 - 4.8 mm;
- 3/8 inch pitch - 5.2 mm;
- pitch 0.404 - 5.5 mm.
For Picco chains, which are equipped with Shtil 180 chainsaws with 3/8 and quarter inch pitches, a file with a diameter of 4 mm is also suitable. It is important to hold it correctly. With respect to the vertical plane, the file must be positioned strictly perpendicular to the chain, and with respect to the horizontal plane - at a slight angle (about 30°). The specific sharpening angle is selected depending on the needs, but within 25-35°.
Unlike sharpening a chainsaw chain on a machine, the angle here can be set using a template, which is considered useful assistant. For this purpose, it is equipped with two slots: SOFT/S (for soft wood) and HARD/H (for hard wood). The template must be secured above the chain, which gives it the privileges of a limiter.
Just keep in mind that this method It is not intended for permanent use, but serves only as a straightening blade. Too much frequent use Over time, a file will cause the chain to wear out, and the teeth themselves will be sharpened unevenly.
Grinder is a good alternative
Professional loggers consider this method primitive and labor-intensive. It is used as a last resort, since the angle grinder cannot be fixed to the template. For this reason, it is very difficult to achieve control over maintaining a constant sharpening angle and depth.
The tire is securely fixed in a vice to prevent its mobility during operation. You should not attach a new one to the angle grinder cutting disc, it is better to use an old circle with a thickness of 1.5-2 mm.
It is better for beginners not to use this method at all - they will be safer. There is a risk of causing serious injury to yourself. In addition, there is no way to do this without skills in working with such equipment.
Modern method
Almost every non-professional is concerned with the question, what is the angle of sharpening the chainsaw chain on the machine? You won’t be able to use a file all the time, it’s difficult to use an angle grinder, and for beginners this procedure is downright dangerous. There’s nothing you can do about it; you have to use machines that can be either mechanical or electric.
WITH manual machine you will have to work for an “eternity”, but you get pleasure from using the electric analogue. Today there are a wide variety of models to choose from that provide
- correct sharpening angle;
- high level of work quality;
- high sharpening speed.
It is also worth noting that sharpening is carried out evenly on all links. All you need is to turn on the equipment to the network, set the desired angle, enjoy the spectacle or do other things. The cost of such machines varies from 2 to 4 thousand rubles. But the most important thing is that it will not be difficult to determine the sharpening angle of the Shtil chainsaw chain on the machine.
At least with manual equipment fiddling around for a long time is a very lengthy process, but it costs several times less. In appearance the machine resembles bow saw, only instead of a blade there is a round file. The smallest tooth is also used as the basis. In this case, two or three movements are enough for sharpening, after which you can move on to the next link. If necessary, process the limiter - change the file (round is replaced by a flat one).
Sharpening rules
Similar sections of each link must be treated uniformly. Otherwise, if there is an excessive selection of metal in any one area, then this ultimately leads to imbalance, unevenness and jerking during operation of the chainsaw. The load on the mechanism increases significantly, which in turn threatens to break the chain.
Therefore, the operation should be carried out at the required angle for sharpening the chain of the Shtil 180 chainsaw (as well as any other tool) with extreme caution, avoiding excessive force. The procedure itself is performed sequentially, that is, you need to start on one side, then finish on the other.
In some cases, you can observe that one cutting edge (or several) has become more sharply ground. This happens when the chain on its way bumps into a knot that occurs when cutting. Then it is necessary to determine which of the teeth has been ground down the most and use it to align all the other links.
After sharpening is completed, you should blow the chain with air from a compressor or pump, and then place it in a container with engine oil for a short time. Usually few people do this, but it will be useful for the chain.
Some helpful tips will help keep your equipment in working order and eliminate the risk of injury. Of course, it is necessary to know the correct angle of sharpening the chain of a Shtil chainsaw. But also important timely care behind the bus:
- Must be monitored, especially if the chainsaw tilts to one side during operation. Poor tension can pose a threat to humans.
- Conduct sharpening in a timely manner, without putting everything on the back burner. It may be expensive, but it is better to give preference to electrical equipment.
- Regularly lubricate the entire chain, otherwise it may fly off (its speed is about 100 km/h). Everyone will draw their own conclusions.
- Do not use used motor oil or any product of questionable quality. You should only choose specialized lubricants. How the best remedy- autol.
Before you start using a chainsaw, the chain should be broken in. Let it run at minimum speed for 40-50 seconds. The lubricant will reach every part, and the chains with the sprocket will heat up a little and rub against each other.
All this expert advice should not be ignored if you want to remain safe and sound!
In conclusion
The sharpening angle of chainsaw chains is selected based on the type of tree that needs to be cut. If you have free time and desire, restoring the functionality of the equipment will not be difficult. Even an amateur who has worked as a file at least once in his life can handle the job. Of course, to do this you will have to spend from 30 to 700 rubles on purchasing a sharpening set. The approximate cost of chain sharpening services at any company is 200-300 rubles. The final choice is up to the lumberjack.
The first chainsaws appeared at the beginning of the twentieth century. The chains installed on them with straight and flat teeth, like modern hacksaws, were characterized by low efficiency, quickly dulled and required very labor-intensive maintenance. For example, when sharpening, it was necessary to take into account that the teeth are divided into trimming, cutting and chipping, have different cutting angles and orientations with respect to the direction of movement (they can be deviated to the left, right or located in the center).
There is no doubt that attempts to modernize the circuits have been made several times, but only one of them was successful. Developed by Joseph Cox and introduced in metal in 1947, the new L-shaped universal sawing chain, thanks to its increased productivity and simplified sharpening, very quickly pushed its predecessor out of the market, and now almost all saw chains“flaunt” the characteristic crescent-shaped profile of the cutting links.
Technical parameters of saw chains
Picking up chain for chainsaw, pay attention to such characteristics as its purpose, pitch, thickness of the drive link, profile height and cutting depth.
It is known that sawing wood cutting along the grain is more labor intensive than cutting across it, and to achieve the best results it is advisable to use chains suited to the task at hand.
The main difference between longitudinal and transverse chains is the angle of attack of the cutting links. For cross-cutting chains, they are 25–35 degrees; for longitudinal sawing chains, the angles are sharper – from 5 to 15 degrees.
The use of chains inappropriate for their purposes can lead to either reduced productivity (if cross-cutting is carried out with a longitudinal chain), or increased “aggressiveness”, strong vibration and additional load on the engine. However, many users prefer not to waste time replacing the chain and longitudinal cuts are made with the same chain as transverse ones, especially if the “quality” of the resulting cut does not require compliance with the “highest” level. Therefore, chains for rip sawing are in demand in smaller quantities, and they are produced in volumes commensurate with demand. It is not surprising that it is much more difficult to buy such a chain than a cross chain. And the issue of purchasing them becomes really relevant if you plan to use special machines like mini-sawmills.
Chain pitch– the distance between three consecutive rivets, divided by two. This is a defining parameter, and depending on its value, all existing chains are divided into five groups with pitches of 1/4″, 0.325″, 3/8″, 0.404″ and 3/4″.
Step 1/4″(6.35 mm) is inherent in miniature chains installed on low-power one-handed saws. True, in Russia they are practically not used.
Chains with steps 0.325″(8.25 mm) and 3/8″(9.3 mm) - the most common options. More than 80% of saws produced around the world are equipped with them.
Steps 0.404″(10.26 mm) and 3/4″(19.05 mm) feature chains with larger links and increased performance. For several decades, they were equipped with Russian-made saws, but now they are installed only on powerful felling saws and harvesting equipment.
Pitch is traditionally measured in inches, and is written as follows: three digits are in ordinary fractions, and two are in decimal fractions. This is necessary to avoid confusion. In particular, the result of converting 3/8″ to a decimal fraction is 0.375″ - a difference from the previous standard (0.325″) of just one digit.
The larger the chain pitch, the larger the links that make it up and the higher its performance. But, on the other hand, the wider the cut, and a more powerful saw is required to overcome the cutting resistance. Chains with a small pitch have other advantages - a larger number of teeth per unit length, smooth movement in the cut and, accordingly, reduced vibration. And their cuts are cleaner.
Drive link thickness(shank) is the second most important parameter. During operation, the chain slides in the groove of the bar, and this sliding should be smooth, without snagging and at the same time without unnecessary “bumpiness”. In a word, the thickness of the shank and the thickness of the groove must strictly correspond to each other, increasing the reliability of the chain fit and eliminating the possibility of it “jumping off.” The international community of manufacturers provides five standard sizes, measured in inches or millimeters (whichever is more convenient): 1.1 mm (0.043″), 1.3 mm (0.050″), 1.5 mm (0.058″), 1.6 mm (0.063″) and 2.0 mm (0.080″).
1.1 mm– such thin drive links are typical for the smallest chains and saws of the appropriate size.
1.3 mm– perhaps the most popular size, typical for household and semi-professional chains.
1.5 mm– ranks second in demand. Installed on more powerful and productive saws.
1.6 mm And 2.0 mm– such thick shanks are found only on chains for highly professional saws.
Profile height. Saw chains are available in high or low profile depending on the height of the cutting edge above the plane of the guide bar. The former are used for professional purposes to obtain maximum performance. The latter are installed on amateur chainsaws, since due to the increased support area of the cutting links and the reduced thickness of the cutting chips, they are safer.
Depth of cut - the size of the gap between the upper edge of the tooth and the cut stop, which regulates the thickness of the chips. Most often, there are samples with gaps of 0.025″ (0.635 mm) and 0.030″ (0.762 mm), less often – with gaps up to 0.070″ (1.778 mm), but they are intended for machine felling units.
The depth of cut largely determines the performance of the chain and its sawing speed. The larger the gap, the higher the performance. But in the pursuit of efficiency, one should not forget about vibration: chains with a small depth of cut in the cut move more softly and “twitch” less. Therefore, manufacturers, in an effort to balance vibration and performance, very often install cutters with a minimum cutting depth on a chain with a large pitch, and vice versa.
Engine size. This parameter characterizes the saw and, it would seem, has nothing to do with the chain itself. However, catalogs and brief annotations for chains often list the engine sizes they are designed to operate with. And these recommendations should be followed. A chain installed on an engine that is too powerful for it will experience heavy loads and fail ahead of time, never having exhausted its service life. Variations in the load on the motor and other important components of the saw itself.
Chain components
Any saw chain consists of three types of links: cutting, driving (shanks) and connecting. The strength of the connection is ensured by rivets.
- perhaps the most complex part of the saw chain, actually consisting of two parts: a cut depth limiter and a cutting element with an L-shaped contour cutting angle.
The upper cutting edge of the link is always wider than the chain and bar itself, due to which the cut is quite free and the cutting resistance is minimal. The tooth works on the principle of a plane: the further the knife (upper cutting edge) is extended above the plane of the plane (cutting limiter), the thicker the chips.
The performance characteristics of the cutting link are determined by numerous factors, namely: the sharpening angle of the top edge and its working, cutting angle, the angle of the side edge (angle of attack) and the height of the cutting stop. When sharpening, the values of all these parameters must be strictly maintained, since even a small change can lead to negative consequences.
The cutting teeth are right-handed and left-handed, and they are fixed alternately on the chain. But in general, incisors are divided into types depending on their profile. Upon careful study of the “shapes” formed by the upper and side edges, two “borderline” options can be distinguished: a “seven” with an acute angle between the edges and a rounded “sickle”. The first option is called chisel (from the English chisel - cutter, chisel), the second - chipper (from the English to chip - chop into chips).
Chisel teeth are characterized by high cutting performance and speed. Due to their configuration, they have a smaller contact area with the wood during operation, which reduces cutting resistance. This is a professional option, but it is very sensitive to an abrasive environment, quickly becomes dull when working with “dirty” wood, and when sharpening it requires precise adherence to all angles and parameters.
The crescent-shaped profile - chipper - is less effective, since its contact area with the wood is somewhat larger, but it is also much easier to care for - the rounded corner does not respond so painfully to minor errors during sharpening. Such links are good when working with contaminated wood.
All other profile options are various modifications of the two described above.
The top and side edges of the cutting element are usually covered with a thin film of some hard metal. Most often it is chromium, but sometimes a nickel-phosphorus alloy is used. The coating applied by the galvanic method significantly improves the anti-friction properties of parts, increases wear resistance, hardness and, in fact, does all the main work of cutting wood fibers. The steel “core” serves as a substrate or base for the coating.
Leading links(shanks) ensure the movement of the chain, transmitting rotation from the engine through the drive sprocket, as well as a stable position of the chain on the saw bar. In this case, the chain moves along a special groove provided in the design of the guide bar. A “side” responsibility of the drive link is to distribute the lubricant from the drive sprocket (where the oil pump supplies it) throughout the bar and chain. It should be noted that the number of shanks plays a major role in designating the chain length for a certain length of the saw bar, which facilitates the correct selection and compliance with the standard size.
Connecting links, true to their name, they combine the cutting and driving parts into a single whole, called a saw chain.
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Technological improvements
Developed by Joseph Cox, the cutting link concept has changed little over the years. Of course, they tried to modernize it, but all the improvements made concerned either the lubrication system or the fight against vibration and kickback.
Lubrication system. Chain and bar lubrication is a very important factor. The design of chain saws includes a pump that supplies oil from the tank to the cutting system through special holes. But then the chain itself distributes it. The shanks, passing the sprocket, “capture” the lubricant and “drag” it along the entire bar and chain. This is why they design the lower part in the form of a hook - so that they “grab” more and “lose” less. To additionally retain the lubricant, special holes are drilled in the shanks or channels are milled. The lubrication system often uses connecting links - additional recesses are made in them for lubrication.
Abundant lubrication reduces friction and heat, thereby not only increasing the service life of each element, but also reducing chain stretch. So constant control over the lubrication process is in the interests of every user. It is carried out quite simply: when accelerating the chain, microscopic drops of oil (if it is supplied in sufficient quantity) form an oil trace in the form of a strip on any light surface (for example, on a tree trunk that is about to be sawed), if you bring the end of the bar to it. The absence of a trace is an alarming signal indicating a lack of lubrication and requiring an immediate solution to the problem (checking for oil, cleaning the tire groove, adjusting the pump, etc.). And one more thing: modern chainsaws allow the installation of chains and bars of various lengths, but before using a new headset, you need to make sure that the oil pump can handle its “processing”.
To improve the lubrication process, many manufacturers in Russia offer special oils. They are made from a plant base (for example, rapeseed) using polymer additives that self-neutralize within two hours when contacted with plants and soil. In addition to environmental benefits, the lubricating properties of these oils are 30% higher than those of automobile oils. And their consumption is about 25% less.
Combat vibration and kickback. Vibration is dangerous because, as a result of its prolonged exposure (as happens, for example, among professional fellers), the so-called Raynaud's symptom can develop: as a result of deterioration in blood supply, the fingertips lose their sensitivity and react painfully to temperature changes.
The desire of manufacturers to reduce the harmful effects of high-frequency vibrations comes down mainly to the development of special shock-absorbing parts. The cause of vibration is the constant collision of cutting teeth with wood. The moment the cutter hits the wood with its working edge, it stops for a split second, being sandwiched between the wood and the guide bar. In this case, part of the impact energy is transferred by the wave through the chain and drive sprocket to the operator’s hands. Another part is also communicated through the chain to the guide bar and, again, to the operator’s hands. If you reduce the impact force, the vibration level will also decrease.
The beveled cut stop helps reduce shaking - thanks to it, the chain moves more smoothly, and the wood slides off the cutting tooth more smoothly. Special shock-absorbing protrusions on the driving and connecting links also serve the same purpose.
Another effective method is a beveled or raised heel of the cutting link. This design allows the saw chain to sag slightly when the cutting tooth hits the wood, and the link does not immediately hit the bar, and the force of this impact is noticeably reduced. As a result, not only vibration is reduced, but also bar and chain wear.
These structural elements are also designed to help with kickback - a situation that occurs when the user touches any hard surface with the toe of the tire while the chain is moving (if we draw an analogy with a watch dial - the sector “from 12 to 3 o’clock”). At the same time, the saw rebounds sharply, creating a traumatic moment. The beveled cutting stop and shock-absorbing lugs minimize this effect.
The order of the links
Saw chains are classified based on their dimensions, design features and the order of the links. It can be standard, semi-pass or skip. In the first case, there are two leading links for each cutter. In the second, every third cutting link is replaced by a connecting link. And finally, in the third case, a connecting link is installed in place of every second cutting link.
It is almost impossible to purchase a ready-made chain with a “non-standard” alternation of links - they are not found in stores. It’s another matter if the chain is riveted independently. An artificially high distance between the incisors reduces their number, and, consequently, reduces the cost. However, increasing this distance increases vibration, reduces productivity and cutting speed.
Care and maintenance of saw chains
The saw set - that is, the chain, bar and drive sprocket - is a consumable material, and, naturally, when purchasing, the user is interested in the question: how long will this material last? But there is no exact answer here, since the “shelf life” of the above parts largely depends on the type of work that will be performed with their help, on the degree of care for them, etc. Contaminated cutting material and careless handling will significantly reduce the service life. For example, if you touch the ground with the tip of the tire while working, the sharpening quickly “goes away” - sand (i.e., abrasive) in combination with a high speed of movement “takes it down” very quickly. A nail in an old log being cut for firewood can sometimes destroy even a new chain without any hope of resuscitation. And there is no need to remind that such moments are dangerous not only for the chain and saw, but also for the operator himself.
If all the parts are lubricated on time and efficiently, and the teeth are properly and accurately sharpened, then one tire will be enough for approximately one drive sprocket and three to four chains. Moreover, it is advisable to use the chains alternately: today – one, tomorrow – another, and so on in a circle. Then the tire, sprocket and chains themselves will wear out evenly. If you use only one chain, leaving the others “in reserve,” then when it comes to their turn, they will work with “slippage,” experiencing additional dynamic shocks when moving, and will fail much faster. And all because the drive sprocket wears out according to the configuration of the shanks of the first chain.
Running in a new chain– a sequence of actions recommended by experts that ensures a long “working” life. The first step is to soak the chain in oil for several hours. The meaning of the event is obvious: the lubricant has time to flow into all the small cracks and reliably “saturate” the parts and rubbing joints. The second step is to install the chain on the tire and briefly “run” it at idle speed. After stopping the engine, you need to check the tension of the chain and, if necessary, tighten it, after cooling it. And after this, after making several cuts with minimal pressure on the bar and rechecking the chain tension, proceed directly to work.
Chain tension- a very important point. A chain that is not tensioned enough will dangle and may jump off the tire or even burst. Reupholstering also does not bode well - it will cause excessive wear and increased load on the engine. In addition, the design of almost all saws is such that tensioning the chain also strengthens the bar - in a “relaxed” state, the bar moves freely left and right. To check, just at the top of the bar, approximately in the middle or a little closer to the tip, take the chain by the tooth and pull it up. When properly tensioned, about a third of the shank remains in the bar groove. If more, the chain is overtightened; if less, the chain is undertightened. In this case, the chain itself should move freely by hand.
Lubrication. We have already mentioned the need to thoroughly lubricate the chain. But even if the chain and saw are equipped with various lubrication improvement systems, pre-soaking the chain in oil will not harm it, but, on the contrary, will reduce wear caused by friction and ensure a longer service life.
Chain sharpening requires compliance with two rules. Firstly, you should control the sharpness of the corners of the cutting link, the height of the cut stop and the compliance of these parameters with those initially specified at the factory. And, secondly, clearly control the identity of the dimensions of all cutting links of one chain.
What are the consequences of non-compliance with these principles? So, if the angles on all cutting elements are the same, but incorrect, the user risks either reduced performance or increased vibration and load on the engine. At different sharpening angles, due to the uneven load on the cutting elements, vibration will increase and the likelihood of chain breakage will increase. In any case, it will be guaranteed to fail prematurely.
That is why all the teeth of the chain must be sharpened evenly and at the same initially specified angles, which, by the way, were established experimentally. Then the chain will serve as long and efficiently as possible. This is not a very difficult task; special devices for sharpening a chain allow you to maintain the specified parameters without thinking and without resorting to precise measuring instruments.
Another important point is to monitor the slightest cracks, abrasions and bruises that can lead to a chain break. If the chain breaks during operation, it slips off the tire and flies down at high speed, under the operator’s feet. To avoid accidents, all saws are equipped with a chain catcher in the form of a protrusion. Still, extra attention won't hurt.
Every user will be interested to know that any new chain sealed in a bag is just a stamping, and by sharpening it, you can increase productivity by about a quarter. In addition, with new chains, the height of the cut stop, and in fact the thickness of the resulting chips, is automatically “adjusted” to the minimum value, i.e. for working conditions in “harsh” conditions (winter, frozen and hard wood, etc.). And if sawing is carried out in the summer, and its object is freshly cut pine, there is a reason to adjust the limiter (using a special template) to speed up the work.
Tools for maintaining saw chains
Files for sharpening saw chains are selected individually for each chain, focusing on its pitch
Files for sharpening saw chains there are round and flat. The first ones are needed directly for editing cutting angles top and side edges. They resort to the help of the latter if it is necessary to correct the cut stop.
Files are selected individually for each chain, focusing on its pitch. Thus, low-profile chains with the most common pitch of 3/8″ are sharpened with a tool whose diameter does not exceed 4 mm. By the way, when sharpening a link, you should make sure that about a fifth of the file protrudes above the cutting edge.
Round files are often equipped with “holders”, “files”, “mandrels”, “calibers” - thin metal plates with engraved straight lines making it easy to track angles. The operator can only ensure that the tire is positioned strictly parallel to the desired strip. And a couple more mandatory requirements: the tool needs to be moved only in one direction, with the same number of movements for each tooth - this will ensure uniform grinding of the chain elements.
For every two or three sharpenings of the tooth, the cut stop is also sharpened, since the difference in height between it and the upper cutting edge should remain unchanged. To control this parameter, a special gauge is provided - a metal plate with a slot. It is “put on” the cutting tooth and with a flat file the stop “peeking out” from the slot is ground down to the caliber level.
Marks are applied to the cutting teeth and the cut stop, indicating to what extent they can be ground. As soon as the length of the upper edge of the tooth is equal to the notch, the chain has exhausted its service life and requires replacement. Over time, files also fail and become greasy.
Manufacturers often combine round and flat files and gauges into so-called sharpening sets, matched to a specific type of chain. Sometimes, in addition to two files and a gauge, they contain some other auxiliary devices. For example, Oregon “diversified” its kit with a tire groove cleaner - a kind of metal hook for removing sawdust from it.
Sets of files of various configurations, handles for them and calibers are found in the assortment of such manufacturers as Bahco, Husqvarna, Oregon, Stihl, etc.
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Manual saw chain sharpening machines are attached directly to the guide bar.
Sharpening machines serve the same purpose as files, but their help is usually resorted to when the chain is heavily worn or for large volumes of such work. Such machines are not uncommon in “specialized” workshops and service centers.
Manual machines are adapted for installation directly on the guide rail. In principle, their main duty is to ensure that the file moves in the desired direction and eliminates even the possibility of deviation. In essence, they perform the same role as calibers, but their accuracy is an order of magnitude higher.
Electric sharpening machines usually sharpen chains that are heavily worn and cannot be sharpened with a regular file.
Electric machines require a stationary workplace, but are also serviced according to highest level. For example, sharpening machine Oregon 32653A fits any chain from any manufacturer, the main thing is to install a sharpening wheel of the appropriate size. Using special scales, the disc and chain to be sharpened are set at the desired angle. There are several modifications of this machine. Thus, the Oregon 106540 model is distinguished by a hydraulic system that provides automatic clamping of the vice when lowering the disk onto a chain tooth and during the sharpening of each tooth. The 106360 machine requires a 6-8 bar compressed air source to operate, but its performance is much higher.
Stihl also did not let its followers down by releasing an electric sharpening machine for all Stihl chains. If you have additional equipment, the machine is suitable for servicing the cutting systems of a wide variety of devices - brush cutters, brush cutters, hedge trimmers.
Similar electric machines are also available in the Alpina product range.
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What distinguishes professional lumberjacks from those new to this business is that the former understand exactly how to determine the quality of a chainsaw. It makes little sense to take into account the power of the device alone, since the configuration of the cutting element is of decisive importance. In the case of a chainsaw, this element is a chain, which consists of cutting, driving and connecting links. The cutting link includes a depth limiter and the cutting part itself, the operation of which is somewhat similar to a plane, that is, the thickness of the chips depends on how far the upper edge is extended. The leading link takes on the function of rotating the chain along the groove and distributing the lubricant, and the connecting links are designed to connect the remaining elements of the chain to each other. Their construction always takes place at a strict angle, the same applies to subsequent sharpening, since the slightest change in the angle in one direction or another will lead to the chainsaw not working.
The first time such tools began to be used back in 1920, but then the teeth were flat and straight, which could not but affect the final cutting result, and it was quite difficult to work with such a saw. A certain breakthrough in this area occurred in 1947, when a fundamentally new type of chain teeth was introduced - the L-shaped shape made it possible to cut the material much faster, in addition, the process of sharpening the teeth was simplified, so it is not surprising that the invention of Joseph Cox, who proposed such idea, in a short time it became a sales leader. If we consider our days, then almost the same version of the chainsaw has reached us, which is based on a chain system with a crescent-shaped cutting profile, for which the type of wood does not play a significant role.
What to look for when selecting a saw chain?
Key characteristics of a saw chain include pitch, shank or drive link thickness, cutting depth and profile size, and chain length. The direction of the cut should also be taken into account. It is from these parameters that you need to start when purchasing a chain to replace a worn one, or when you need to purchase a chain for some special needs. To avoid mistakes, you can look at the device passport, where the manufacturer indicates the main parameters of the saw. If we are talking about the initial purchase of a tool, then these parameters themselves must correspond to the purposes of using the chainsaw.
This parameter is a value in millimeters, although in the documentation it is customary to write inches. It is calculated by dividing the distances between three rivets by 2. It is based on this characteristic that it is customary to divide canvases into several main groups:
- Step in 0.25 in (6.35 mm) used in devices with minimal power, which are suitable exclusively for country work. It will not be possible to cut large logs with such a pitch. Chains for chainsaws with this pitch are not very common.
- The next two groups where the step is used 0.325 and 0.375 inches (8.25 and 9.3 mm respectively) are the most common of all, since approximately 70% of all chainsaws produced in the world belong to these groups. Accordingly, they can be used for most existing household tasks. But there is one little trick! Since it is quite easy to confuse the numbers 0.325 and 0.375, chains with a pitch of 0.375 are designated 3/8, that is, 3/8 inches.
- The last group in increments of 0.404 and 0.75 inches (10.26 and 19.05 mm) used for the most complex tasks. In this case, we are talking about a logging tool rather than a saw for household use. That is, chains with such a pitch can only be found on professional chainsaws.
There is a direct relationship between the step size and the performance of the tool, but you also need to take into account that a large step requires a more powerful motor. The cutting quality of devices with large pitches is still inferior to devices from the first three categories, since the teeth there are more densely spaced. For a power of 2.5 liters, a step of 0.325 mm is suitable, and for a more productive chainsaw it is better to install a saw blade and chain of 3/8 mm, as this will help unleash the saw’s full potential.
Drive link thickness
In this case, a division into several main categories is also used in accordance with this parameter. We are talking about thickness values such as 1.1; 1.3; 1.5; 1.6; 2 mm (0.043’’, 0.050’’,0.058’’,0.063’’,0.080’’). This characteristic, measured in inches, affects how smoothly the cutting blade will move while the saw is running.
- Chains with a pitch of 1.1 mm are used on low-power household chainsaws, as well as on chainsaws intended for (carving).
- 1.3mm pitch chains are more common. For example, the famous chainsaw is equipped with chains with exactly this pitch. And in general this is the most popular step.
- Pitches of 1.5 and 1.6 mm have chains that are intended for professional and “semi-professional” (farm) chainsaws.
- 2 mm - this pitch is found exclusively on chains installed on very productive and powerful chainsaws in the professional segment.
Low and High Profile Chains
What do you need to know about chain profile height? It determines what the cutting depth of the saw will be. Based on this parameter, the saw can be either low or high profile, respectively, in the first case the chips will be removed thinner, but the work will be somewhat slower, while in the second case the depth and productivity will be greater. For low-profile tools, a parameter of 0.635 mm is used, and for high-profile tools, 0.762 mm is used. If we consider devices for domestic use, they are always low-profile, while professional equipment can be produced in two versions. At the same time, in order to stabilize the vibration that inevitably occurs during operation, manufacturers make a balance between the profile height and the number of steps. For a small step, make a high profile, and vice versa. Failure to comply with this rule will lead to the fact that it will be impossible to work with a chainsaw for a long time, although the wood will be cut very quickly. This balance must be maintained if there is an intention to sharpen at home; in all other situations, all that remains is to choose a saw for the home or for professional cutting.
Main types of links
If we consider the most common types of links, then these are chisel links that can most often be found on professional equipment, and chipper, which are supplied for simple chainsaws. The first option in cross-section is a little similar to the number 7, and this design allows you to work with the saw as quickly as possible, since the link digs into the material evenly. Cutting occurs more accurately, but sharpening such links at home is extremely difficult, since the slightest deviation from the permissible angle eliminates all the advantages of this design. In the case of a chipper, there is no need to maintain strict angles; also, such a link is not so afraid of contamination, although there is a higher load on the tool. For home use, the second option is more suitable, especially if you don’t have the skills to sharpen a saw. As for the material, chromium-nickel steel is mainly used, although in special cases, if you need to work with particularly durable material, the teeth can be tipped with carbide, as evidenced by the markings on them.
Chains for rip and cross cuts
The name of the chains corresponds to the direction for cutting fibers they are intended for. For working across acute angle There is no need to sharpen the link, since the resistance of the wood is not as great as when working in the longitudinal direction. Each type of wood requires the choice of one direction or another, and if we are talking about professional work with wood, which also involves longitudinal cutting, then you will need to sharpen the teeth to 5-15 degrees, while for work at home 25-35 degrees is enough . Demand for longitudinal chains minimal, since for longitudinal work it is more reasonable to use circular saw. It happens that it is quite difficult to find a model that works lengthwise, even in a specialized store. For work at home, it makes no sense to look for such a saw, since cross-cutting devices will perform all household tasks without difficulty.
How to determine whether a chain is suitable for longitudinal or cross cutting?
- For cross cutting, the chain sharpening angle is 30 degrees.
- For longitudinal sawing, the sharpening angle of the saw chain is 10 degrees.
Stihl's rip saw chain is designated PMX. For example, STIHL 63 PMX 50.
Oregon will have the letter R in its chain model index. Example: 73RD100R
Is the sequence of the cutting links important?
In the usual case, when a saw is manufactured at a factory, it is customary to place two driving links on one cutting link, thereby making 50% of the total cutting teeth. Then the productivity of the equipment remains at the same level, and the quality of the cut does not suffer, but in order to reduce the cost of the chain, the cutting links can be placed not every step, but after one or even two steps, which will lead to total quantity cutting links up to 37.5%. A chainsaw will become cheaper, but the quality of cutting will greatly deteriorate, so such devices better attention don't pay attention.
Carbide chains
Such chains are much more expensive, and they have a special purpose - working with frozen wood or contaminated material. In all other situations, the money will be wasted, since for simple wood there is no point in carbide brazing.
Major chain manufacturers
Almost any online store or specialized salon offers chainsaw components, including chains, from Husqvarna (Sweden), Oregon (Canada), and Stihl (Germany). Each manufacturer has its own advantages over its competitors, but the quality of products produced by these companies is at approximately the same level.
Video about chainsaw chains