At What Angle To Sharpen The Chainsaw Chain
Chainsaw chain sharpening with your own hands Chainsaw chain sharpening with your own hands The chain tooth planes wood like a plane, and the thickness of the shavings is regulated by the height of the limiter. Intense sawing results in rapid dullness
The round file holder has a mowing line that can be correctly positioned in relation to the chain. The holder fits onto the sharpened tooth in accordance with the line orientation. In this case, the insert itself rests on the upper edge of the tooth and the depth gauge, and the file is located under the cutting edge.
The use of a holder ensures that the file will fit to the tooth at the correct height. There are different holders for different pitches of the saw chain. The correct choice of holder, combined with the correct file diameter, ensures that the file protrudes over the back of the tooth by 1/5 of its diameter. Use only special saw chain files.
Before sharpening the chainsaw chain, it is advisable to secure the bar. When sharpening, it is necessary, keeping the position of the holder and pressing the file to the sharpened edge, to make several (2-3) turning movements away from you. Do not try to press too hard on the file, the movements should be smooth and measured. Rotate the file regularly to avoid one-sided wear. All other teeth are sharpened in the same way. It is more convenient to first sharpen the teeth in one direction, then change the position and do the same with the teeth in the other direction.
When sharpening all teeth, file the same number of strokes at the same pressure. This will result in the same tooth length. All cutting teeth must be of the same length. Different tooth lengths cause uneven chain running and cracking. If the length of the teeth is not the same, all cutting teeth must be filed to the length of the shortest tooth.
After several sharpening of the cutting teeth, the depth gauge is ground. To do this, a template is superimposed on it so that the limiter falls into the slot, and the tip protruding from the slot is grinded with a flat file.
The principle of using another set for sharpening chainsaws is no different from the first, although its design is different.
A round file is also used for sharpening the cutting tooth, and for sharpening the depth gauge. Flat. A special template provides parameters for sharpening both cutting teeth and stops. In the first case, it is superimposed on the chain in such a way that it falls into its slots. The file, placed on the template and brought under the cutting edge, rests on the guide rollers. The direction of movement of the file must be parallel to the lateral edges of the template.
When sewing the stopper, the template is applied so that the stopper falls into the slot, near which it says SOFT (for soft wood) or HARD (for hard wood). As in the case of the first device, the file is seamed with smooth, even movements of the flat file away from you.
General rules for sharpening chainsaw chains
Do-it-yourself chainsaw sharpening
The chain tooth planes the wood like a plane, and the chip thickness is adjusted by the height of the stop.
Intense sawing will quickly dull the chain. Several sharpenings may be required within one day. The problem is aggravated by the fact that the tooth quickly dulls when it meets the ground. It is enough to hook the soil with the tire once or twice, and the work can be stopped. The shavings become fine and the saw stops going deep into the wood.
The sooner dull teeth are sharpened, the less material needs to be removed during sharpening, as a result. The service life of the saw chain is longer. Determining the moment when sharpening is already required is quite simple. An important feature is the feed force. A properly sharpened chain is pulled into the cut with just a little pressure. If, on the contrary, the chainsaw is forced to cut by increased feed force, then the teeth are dull. A dull chain can also be recognized if only small chips fly out of the cut instead of coarse, thick chips.
In this situation, the chainsaw must be sharpened urgently. Do not cut with a dull or defective saw chain. The consequence is high stress in the body, high cyclic load, poor cutting results. In addition, this means reduced productivity, high fuel consumption and increased wear on all parts of the chainsaw.
A set of tools required for sharpening saw teeth:
- Flat file, which is taught to use in labor lessons at school. With it, the depth gauge is grinded.
- A round file of a certain diameter, required for cutting a cutting tooth. An additional device is attached to it. A holder with fishing lines, which suggest how to properly hold the tool in relation to the chain. The holder is placed on the saw tooth, taking into account the guiding lines, the position of the file is under the cutting surface.
- A template that serves for editing and observing parameters.
- The hook is needed to remove sawdust from the chain.
Metal sharpening templates help you calculate the sharpening depth
Device and shape of the teeth
First of all, you need to understand the structure of the chain tooth, which must be sharpened. The tooth cuts wood like a plane. It has a complex configuration and an unusual cutting surface. Two edges: one of them is lateral, and the other is upper, slightly beveled. The adjustable tooth stop adjusts the chip thickness. Of course, sharpening such teeth is much more difficult than, for example, a kitchen knife.
Chainsaw teeth have a more complex shape than other sharp objects to be sharpened
In this case, the correct angle of sharpening of the chainsaw should be set. It is clear that it is difficult to operate with one file, therefore there are various accessories that help to adhere to the exact parameters of sharpening. These kits are sold complete with chainsaws, as well as separately.
The diagram shows the angles of inclination that must be observed during sharpening
When sharpening, the location of the tool should be chosen correctly. The round file was not chosen in vain. Because of the rounded shape of the inner contour of the tooth. The edge of the file should be 20% higher than the cutting surface of its diameter, and the choice of diameter is influenced by the length of the chain pitch (usually 4 mm to 5.5 mm). The procedure should be followed: first, the cutting teeth are processed, then the stop tooth.
When is it time to sharpen the saw?
The periods between two sharpenings depend on the frequency of use of the tool. Some use it daily, others several times a year.
You can understand that the teeth are dull by some signs that come to light during operation:
- The chain stretches and sags, causing the saw blade to function inaccurately and slow down in the cut. Working with such a chain requires additional effort.
- The sawing process slows down, productivity drops, and you have to spend twice as long on work.
- The type of sawdust changes: they become uneven, sharp, and smaller. Shavings from a sharpened saw looks different: the same pieces of an even rectangular shape.
If the saw loses accuracy and gets stuck in the cut, it’s time to start straightening the chain teeth.
Repair work should not be postponed for a long time. The sooner you sharpen, the less material you have to grind, and accordingly, the longer the service life. And you don’t have to work with a blunt instrument for a long time, increase its wear and tear and waste your own physical strength.
Two samples of shavings: the first is the result of a saw with a sharpened saw, the second is dull
How to understand that the chain is dull
- Increased physical effort;
- Sagging (stretching) of the chain;
- Vibration and “braking” cutting passage;
- Inaccurate sawing and change in the type of sawdust (they become uneven with sharp “needle” edges, small and dusty). It already aboutAnswer the test.
“In the opinion of experts, and in my opinion too: well-sharpened teeth are more important than engine power.”
Why dull? The reasons are generally known, but I will name the main ones:
- Intense or voluminous work;
- Accidental contact with stone, earth, hard knots, etc.;
- Mishandling (broad term).
Chainsaw teeth have a specific geometry. You need to understand and know what part of them should be sharpened. In general, the “logic” of cutting wood resembles a plane.
The cutting surface has two edges. One side, the other slightly beveled. The cutting depth limiter adjusts the thickness of the chips. Let’s take a closer look. The elements of the cutting-working link are arranged as follows:
- Base with axle holes;
- Tooth scapula;
- Cutting depth limiter;
- End face of the blade (placement. Vertical);
- Upper edge of the blade (placement. Horizontal);
Sharpened edge Dull After touching the ground
Do not over-grind or change the location of the links. The normal operation of the instrument depends on the identity of their location. Otherwise, increased stress on the chassis, tire and engine is likely. The cut can be crooked. There is also a small chance of breaking the circuit.
Possible ways and methods of sharpening the chain
When purchasing a chainsaw, it is advisable to acquire a special template with which you can easily set the optimal values of the tooth angles. With its help, the values of the back angles of the upper and end blades are controlled, 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 value of the clearance angle of the upper blade. This angle of sharpening of the chainsaw chain is very difficult to determine otherwise, but meanwhile it must be maintained within rather limited limits. From 50 to 60 °.
Measurement of the sharpening angle is performed by determining the angle between the upper cutting edge and a line perpendicular to the chain guide.
The angle of sharpening of the chainsaw chain can be changed, depending on what kind of work will be done. As the hardness of the wood increases, its value should be lower. In general, it is considered the optimal value of the angle 10. 12 °. With a longitudinal cut, and 25. 30 °. With a cross cut.
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 in relation to the sharpened tooth. The upper edge of the working part of the file is approximately one fifth higher than 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. You will need a flat file to sharpen the limiter, and a hook that removes the resulting sawdust to clean the work area. There are also special holders on the market, on which the mowing line is graduated with the direction of movement of the file relative to the axis of the chain. As seen from Fig. 4, the holder can be installed on top of the tooth 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 set in order to obtain the correct sharpening angle of the chain by hand is shown in fig. Five.
First, the teeth are sharpened in one direction, and then in the other. Start with light pressing of the tool away from you, gradually increasing the load. During sharpening, the round file is periodically rotated along its axis.
Chainsaw chain sharpening angle. How to choose the right one?
Even the popular Stihl does not last forever: once the teeth of a chainsaw wear out, which is easy to determine by the nature of the chips formed. With a blunt cutting edge, the chips are small, because the working edge does not cut, but crumples the wood. Naturally, the effort expended by the operator increases dramatically. It’s time to sharpen the saw. How to do this correctly. Choose the optimal technology, establish what angle of sharpening the tooth should be and how to check it?
External signs of a blunt cutting edge of a chainsaw tooth
Recall that the 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: the lateral one, which is located perpendicular to the axis of movement of the links, and the upper one, located at a certain angle to the direction of the chain movement. In addition, a limiter is provided on each tooth, the parameters of which determine the height of the removed chips. Since the main cutting effort falls precisely on the working angle, then all subsequent work with the tool will depend on which angle to sharpen the tooth.
Before starting long-term work with a chainsaw, she needs to inspect and perform test sawing, as a result of which:
- Visually establish the presence (or absence) of a tapered section adjacent to the corner of the tooth, as well as radius curvature on it. The main signs of bluntness (see Fig. 2).
- Check the feed force at which the tool runs stably, with a fast cut. For sharp teeth, the initial moment of penetration of the tooth into the wood occurs quickly, and without significant material resistance.
- Find out the presence of chain vibrations during a steady cut. If they are noticeable, then the teeth must be sharpened.
- Inspect the appearance of the just cut end (especially if the tool is used for ripping). If there are rough chips and dents, the chainsaw chain must be sharpened.