Correct sharpening angle for band saws

Setting the cutting elements of the band saw

Divorce is the bending of band saw blades in different directions. This significantly reduces the friction of the blade and prevents it from pinching. To ensure free movement of the blade against the walls of the material being cut, its width must be greater than the thickness of this material.

Band saw set types

Divorce can take several forms. It may have different names from different manufacturers. Most often it can be:

Standard, which is characterized by the opposite bending of the cutting elements in various directions. It is most commonly used for band saws that cut hard material.
Wavy, which belongs to the category of complex structures. Divorce in this case has a variable meaning. In this case, a kind of wave is formed.

Divorce consists in folding not the entire canvas, but only a certain part of its top. The parameters are determined strictly by the tool manufacturers. Their range is 0.3 to 0.7 millimeters.

Protecting. The divorce consists in bending two teeth. In this case, the third remains in place. Designed for band saws for the processing of extremely hard material. In shape, every third tooth resembles a trapezoid. The location is the center of the canvas. With its help, the most correct direction of the saw band is carried out.

Woodworking machines are characterized by a versatile sawing tool design. The spread for soft rock processing must be larger than for hard rock equipment. But the divorce should not be such that the wedge is located in the center without a cutout. The divorce must be characterized by the same arrangement of all cutting elements. It is necessary to spread the teeth in such a way that the deviation is no more than 0.1 millimeter. If the saws are unevenly positioned, this will lead to the fact that the band saw equipment will move to the side during operation.

Shapes of the cutting part and the angle of sharpening of the blades

The geometry of the cutting elements of band saws can be varied, which directly depends on the material that is intended for cutting. Woodworking machines are most often equipped with special saws, with which you can carry out:

carpentry work;
sawing logs and beams;
use on dividing saws.

The sharpening angle is determined strictly by the tool manufacturer. The rake angle will be as small as possible when using hardwood. Band saws for metal are equipped with saws with different blade shapes, which directly depends on the metal used for sawing. If it is necessary to cut thin-walled metals and at the same time have thin chips, the rake angle when sawing will be equal to zero, then standard cutting is used. The sharpening angle can be varied. It directly depends on the structure of the device.

A tooth that has a positive rake angle is found in saws commonly used for cutting thick-walled metal. The step of the blade, with the help of which the sawing of thin metal is carried out, is quite small. In order to cut thick-walled metal, it is necessary to use devices that have a large number of blades. In some cases, the equipment has a variable pitch to eliminate the resonance effect. The change in the distance between the teeth directly depends on a certain group.

Saw band design

Band saws are a special continuous design characterized by the presence of cutting elements on one side. This is the cutting element with which woodwork is carried out. Most often, band saws are used in a variety of band saw blades. With their help, cutting of various parts is carried out. With the help of these blades, a sufficiently high cut quality is ensured. All this is provided only if the saw has a good set. Also, the tool must be serviced in a timely manner.

Band saws are made of heavy-duty metal, which ensures not only high cutting quality, but also the saw’s durability. The teeth have a universal angle, which allows for the highest quality cutting of the material.

Sharpening and setting band saws

In order for the processing of various materials to be carried out correctly, it is necessary to look after and monitor the condition of the band saws. For this purpose, machines for sharpening and setting band saws are used. Timely care will ensure long-term use of instruments.

Sharpening recommendations

During the work of the canvas, its rupture is very often observed. This is due to the fact that it is poorly sharpened. This is due to the concentration of stress in the blade profile, if the sharpening is carried out at a low-quality level. The need for the procedure is determined by the condition of the band saws. If the surface roughness of the cut increases, then this leads to dullness of the tool.

Sharpening of the tool is carried out using diamond, electrocorundum, CBN discs. Their choice directly depends on the characteristics of the material being processed. The sharpening of the blade, the material of production of which is tool steel, is carried out with corundum wheels. The procedure for bimetallic tools is carried out correctly if a diamond or CBN wheel is used. The instructions will tell you how to carry out this procedure. The most important thing is that the angle does not change in the process.

Wheels of various diameters can be used for sharpening. The choice of one of them is determined by the parameters of the device. For this purpose, profile, flat, dish-shaped, cup circles are most often used. Sharpening is correct if the peripheral speed is 20 to 25 meters per second.

The principle of sharpening tape blades

In order for the band saw equipment to work efficiently, it is necessary not only to select it correctly, but also to sharpen it in a timely manner. For this purpose, special circles are most often used. This procedure is as simple as possible, which allows it to be easily performed by a master without appropriate experience.

Application of tape blades

The key component of every band saw is the band saw (blade). Bandsaws are widely used when working with wood, metal, rubber, plastic and various flexible materials.

There are three types of these products.

Manual tape devices. these machines can be called household machines, they are most often used at home.
Desktop modifications. these units are more often purchased for small industrial facilities, woodworking companies, workshops.
Stationary units. such installations are related to the category of professional ones, they are used in large industries, factories, factories, large workshops, and so on.

Features of sharpening band saws

Application of tape blades
Typology of paintings
Drank service
Features of the cultivation of tape webs
How to correctly sharpen the canvas?
full-profile sharpening
sharpening the edges of the teeth
Sharpening canvases in winter
Possible errors when sharpening

A well-sharpened metal and wood band saw is the key to productivity and tool life. As a rule, such services are provided by special organizations, but if you know the sequence of actions and features of the process, you can sharpen a blunt saw on your own.

Drank service

To service the blades, it is not enough to sharpen the teeth, it is also necessary to dilute them. These two procedures are performed in succession: they start with setting the teeth, and finish them with sharpening. It is required to strictly adhere to such a chronology of works. Breeding is carried out in order to reduce the friction of the saw in the process of cutting a particular material (wood, metal, plastic, etc.). There are several methods of dilution, which depend on what elements need to be obtained subsequently processing and the strength of the starting workpiece.

How to correctly sharpen the canvas?

According to statistics, more than 80% of cases of device ruptures occur due to non-performance of sharpening techniques. The need for sharpening is revealed visually. by the appearance of the teeth themselves or the state of the cut (increased unevenness of the plane).

Stones for sharpening tape blades are selected based on the stiffness of the teeth. For sharpening products from carbon and alloy steel, corundum stones are used. Bimetal blades require borazon (CBN) or diamond discs. The configuration of the blade grinding wheel must be determined based on the characteristics of the tool. It can be dish-shaped, flat, cup, profile.

Before starting work, it is advisable to let the canvas hang in the unscrewed position for 10-12 hours.

Conditions for sharpening canvases with your own hands:

Adjusting your band saw for blade drift

ensuring the systematic removal of metal according to the shape of the section of the tooth;
avoidance of excessive pressure on the disc (this can cause annealing);
ensuring the integrity of the height and shape of the section of the tooth;
the indispensable presence of liquid for cooling;
control of the absence of scoring.

Typical instructions for sharpening blades say that sharpening should be carried out either along the front surface of the tooth, or both along the front and back. But this is theoretical. In fact, most specialists, and even craftsmen from the people, perform it only on the back plane. so, they think, it is more comfortable.

By and large, regardless of the abundance of rules and conditions, these devices are quite undemanding in terms of sharpening. You can deal with them both by means of a specialized sharpener for tape blades, and by hand. In addition, circles of various configurations and substances can be used for processing.

Before sharpening the tape, it is advisable to familiarize yourself with the key methods for performing this procedure.

Typology of paintings

The basis for the separation of saws of this type is the material of manufacture and the elements being processed. In accordance with such aspects, the following types of canvases can be distinguished.

Saws for wood. The key materials for their manufacture are carbon and alloy steel grades, their hardness reaches 40–45 HRC. All teeth are subject to high-frequency current hardening without fail. It should be noted that such a material of canvases can be used to cut thin non-ferrous metals or carbon steels.

Canvases for metal. Such tools are made of high-speed or spring steel (cobalt and tungsten are added to the structure) steel. These saws already have strengths up to 69 HRC. To obtain high hardness and ample opportunities, stellite or other types of strong alloys can be welded onto the teeth.

full-profile sharpening

This method is considered especially high quality and is performed on automatic equipment. Elborovy (borazon) disc, precisely matched to the configuration, processes the entire interdental cavity together with the corresponding planes of adjacent teeth with a single pass. In this case, obtaining an uneven configuration at the base of the teeth is excluded. One drawback of this sharpening is to constantly have at hand a specific number of spheres for canvases for different purposes.

sharpening the edges of the teeth

Can be performed on specialized equipment or manually.

If special equipment is selected, then it is necessary to competently choose a circle. as a rule, these are flat samples. By and large, it is advisable to turn to professional sharpening equipment only in those situations when the scale of work is quite large. It is preferable to carry out irregular “household” work by hand. by means of an engraver or on an ordinary machine. During work, for your own safety, it is imperative to use a mask or goggles.

If your farm does not have a machine tool or an engraver, then you can sharpen the canvas in the usual way. working with a file. Just 3-4 decisive movements on the back or front face of each of the teeth will solve the problem. With constant and diligent work, the skill of good independent hand sharpening will develop very quickly.

Rules for sharpening band saws for wood

Band saw. closed-type cutting tool used on sawmill equipment.

The undoubted advantages of these elements are high productivity and a minimum amount of production waste. It is possible that when sawing ordinary boards, the latter fact does not play a significant role, but when it comes to processing valuable wood, the kerf width and cut quality directly affect the economic benefits.

Correct sharpening of a band saw for wood is a guarantee of production efficiency and tool durability. Usually such services are provided by specialized companies, but if you know the procedure and the subtleties of the procedure, you can sharpen a dull saw yourself.

Characteristics
What you need to know about sharpening angles
How to sharpen a band saw correctly

Wiring
Sharpening

Common mistakes

How to sharpen a band saw correctly

Immediately, we note that if there is no experience and skills in performing such work, it is better to entrust saw sharpening to professionals. Violation of the geometry of the teeth of the cutting edge, the appearance of dross on the metal or incorrect setting will significantly reduce the life of the blade.

Having decided to sharpen the band saw with your own hands, it will be useful to first familiarize yourself with the key definitions, the knowledge of which may be required in the process. So, for the correct formation of the cutting edge you will need:

setting. deviation of the teeth from the plane of the main saw blade;
the height of the teeth is the distance between the top point and the base;
pitch. the distance between the teeth, usually varies between 19-25 mm.
sharpening angle. depends on the intended purpose of the tool; for example, the recommended sharpening angle of carpentry saws is 35 °, indexing. 18-22, intended for sawing a bar. no more than 15 °.

The sharpening angle is determined by the manufacturer, therefore, when self-dressing the saw, it is recommended to adhere to these parameters.

Here are detailed instructions that will help you sharpen a closed saw correctly without resorting to the services of specialists.

Adjust Bandsaw | Drift, Resaw, Blade Guides, Tension, Sharpening

Sharpening

This is the main step in cutting edge dressing and can be done in two ways.

Full-profile saws are sharpened with an CBN wheel installed in a special sharpening machine.

This is a fully automated operation used by professionals. The work of the machine for sharpening band saws for wood is controlled by electronics, and the sharpening wheel processes the entire band in one pass. The disadvantage of this method is that the CBN wheel is selected individually to the profile of the saw, therefore, for dressing different tools, the sharpening element must be present in the assortment.

Sharpening of teeth is performed manually or on specialized equipment.

Note! It is this method that is used for self-sharpening band saws. A regular emery wheel or file can be used here.

In the first case, the sharpness of the teeth can be restored in the shortest possible time, but the work requires certain skills. In the second, painstaking work: 4-5 movements along the edge of each tooth.

For automatic sharpening, diamond, CBN and corundum wheels are used. It is important to understand that when performing this procedure, only sharpness is given to the teeth, the geometry created after setting the blade should remain unchanged.

What you need to know about sharpening angles

The geometry of the teeth of band saws can be modified depending on the characteristics of the material being processed. This is expressed in the shape of the tooth and the distance between the individual elements of the cutting edge.

The band saw profile is determined by the markings applied by the manufacturer. It looks like this:

WM. a universal version designed for sawing soft and hard wood;
AV. used for longitudinal cutting and sawing of hard materials, such as frozen wood;
NV. has a narrow blade width, so it is ideal for shape cutting;
NU. a cutting edge with a wide tooth pitch, which provides high performance when cutting soft wood;
PV. almost a complete analogue of the previous blade, but has a flattened tooth shape;
KV. the profile is used for wide band saws intended for softwood;
PU. wide saw blade for cutting hardwood.

Sharpening Band Saw Blades. Don’t Do It!

The pitch of the teeth is selected individually, depending on the material. For example, when cutting hardwood and metal, only fine-toothed blades are used to avoid damaging the cutting edge. Soft raw materials and thick-walled materials are processed with saws with a large tooth spacing, which allows to speed up the production process.

Wiring

Setting band saws into wood is the first step in restoring the profile of the cutting edge. During operation, the location of the teeth can change, so until the correct geometry is achieved, it makes no sense to sharpen the saw part.

There are 3 ways to open the saw:

classic. the teeth alternately deviate to the right and left sides;
stripper. the 1st and 2nd teeth deviate in different directions, the third remains even. This profile is created for sawing hard materials;
wavy. the most difficult option, resembling a wave in shape. Here, each tooth is individually shaped, and this type of setting is usually performed only in specialized workshops.

It should be noted that when wiring, not the whole tooth is bent around, but about 2/3 of the upper part. The procedure is performed on a special band saw setter. The cost of such a tool is quite high, so they buy it if you need to adjust several tools. Its presence can become the basis of a sharpening business.

Of course, the first time you can do everything correctly, even on an adjustable machine, it may not work, so at least the geometry of the profile should remain the same as before the start of work.

Characteristics

Band saws have three distinctive features. They are made only of special grades of tool steel, which ensures high strength and wear resistance of the teeth. Russian manufacturers usually use steel grades 9ХФ and В2Ф, foreign companies prefer the С75 series. In any case, the hardness of the material must be at least 45 HRS.

The cutting width of the band saw blade is much narrower than that of circular counterparts. As mentioned above, this is a fundamental factor when processing precious woods and industrial wood.

The saws are able to handle workpieces of any length and diameter without any problems. At the same time, a properly sharpened band saw ensures high production productivity.

It is necessary to clarify that the reliability of closed saws is due to the heterogeneity of the material used to make the blade.

In particular, the body of the saw tool is usually made of spring steel, which has incredible tensile and dynamic resistance. Grades of steel with high m of tungsten and cobalt are used for the manufacture of cutting edges. Individual parts of the web are welded together by high-frequency currents. Tools made using this technology can be used for sawing metal.

Common mistakes

If a person tries to sharpen a saw for the first time, it is difficult for him to fulfill all the requirements and remember the nuances of the technological process. However, violation of these rules leads to the fact that the efficiency of using the band saw is noticeably reduced, the load on the blade increases, which leads to premature rupture.

Professionals recommend avoiding such mistakes:

with mechanical sharpening, the abrasive stone is not positioned correctly in relation to the saw profile. In this case, the sharpening of the teeth will be uneven;
excessive force when the saw and the grinding wheel are in contact. As a result, the metal overheats, dross appears, which leads to premature wear of the cutting edge;
burrs remain on the canvas. After sharpening, all roughness must be eliminated, otherwise microscopic cracks will appear on the metal during operation;
using your own sharpening angles. Many inexperienced craftsmen believe that only sharpness is important for saw teeth, therefore they shamelessly violate the geometry of the cutting edge profile recommended by the manufacturer. It is important to understand that the shape of the tooth has been tested over the years; it is useless to try to experiment here.

Instead of a conclusion, we add that each band saw has a certain resource, so the blade cannot be sharpened indefinitely. Manufacturers guarantee correct tool operation until the total blade width is reduced to 65% of the original size.

Setting and sharpening the band saw is half the battle!

The most important factor in the success of a sawmill business is which saws are used in production. The size of the saw is important, and the material from which it is made, and the technology by which it is produced.

But even using the best-sized saws manufactured to the latest standards will not give you the profit you expect if these saws are not sharpened and set correctly. Incorrect setting and sharpening of the saw lead to defects in the lumber, which means that its cost drops significantly.

Correct sharpening and setting of saws is especially important when working on a band sawmill. Unfortunately, in practice, many even confuse the sequence of these procedures: first they spread the saw, then sharpen it. As a result, the spread of the saw tooth “goes away”, and the saw must be diluted again, or, if this is not done, the quality of the finished product will leave much to be desired.

If we talk about the machines on which the saws are sharpened and set, then every detail is really important here. The Emerald Les company has contributed to the development of high-quality adjustable and sharpening devices.

The adjustable saw has the correct geometry: when the saw is installed in the adjustable saw, the root of the tooth is between the cheeks that grip the saw. In many other machines, including those from a number of well-known manufacturers, this condition is not met. Therefore, when bending a tooth, both the tooth and the saw body deviate. Technically correct setting of the saw implies something else: the pusher rests against 1/3 of the tooth and bends only its tip.
In the manufacture of the adjustable machine, two clamping stops are used, which, with light pressure on the handle, press the tooth against the indicator head. The pusher, before reaching the tip of the tooth, shows the actual set on the band saw. If it is insufficient, the operator presses the tooth until it is diluted to the required size. We consider it very important to pay attention to one point: a band saw tooth has such a property as metal memory. Because of it, under the influence of inertia, the tooth tends to return to its original position. Therefore, for correct wiring, it is not enough to make one click on each tooth: it is necessary to act on the tooth several times so that it remembers its position. If someone tells you that it is enough to click on each tooth once, know: you are being misled.

Two clamping stops with powerful springs used in the machine show the actual saw tooth spread, which is very convenient: you do not need to endlessly unscrew and reconnect the pusher to find out how the saw tooth was actually retracted.

Another strong point of the adjustable machine made by the company is the ease and safety of the operator’s work: the spread of the tooth occurs not due to the operator pressing the pusher forward, as in a number of analogues, but due to the operator’s own weight and using the eccentric. As a result, the operator does not have hand sprains.
So, high-quality adjustable and sharpening machines are what, undoubtedly, should be in the arsenal of every sawmill owner. But by themselves, they do not guarantee the quality of lumber, they will not allow the saw to serve for a long time if sawmills that have serious technical flaws are used in production.
For example, if the rollers are made with a cone, or they have become conical because the saw has sharpened them, then even with the correct sharpening and setting, the saw begins to look for its place in the log. This will happen because the rollers are tilted. If the pulleys on the sawmill are divorced and not in the same plane, then the saw is flared not clearly in the middle, but from the sides, and then the stress goes to the edge of the band. It also reduces saw blade life.

So the role of correct setting and sharpening of the saw is, of course, great, but these factors do not determine 90% of quality sawing, as is commonly believed. It’s just that the saw itself will not be able to cut perfectly evenly and not fail for a long time if, for example, a rigid tension is used on the sawmill.

If you are just starting your business and have not yet had time to familiarize yourself with all these nuances, we recommend that you contact those who have been on the market for several years. The telephone number of the central office of the Emerald Les company in Novosibirsk: 8 (383) 249-43-21. Contact us. and we will advise you on the choice of equipment based on your needs and your budget.

Setting the cutting elements of the band saw

Band saw set types

Divorce can take several forms. It may have different names from different manufacturers. Most often it can be:

Standard, which is characterized by the opposite bending of the cutting elements in various directions. It is most commonly used for band saws that cut hard material.
Wavy, which belongs to the category of complex structures. Divorce in this case has a variable meaning. In this case, a kind of wave is formed.

Divorce consists in folding not the entire canvas, but only a certain part of its top. The parameters are determined strictly by the tool manufacturers. Their range is 0.3 to 0.7 millimeters.

Protecting. The divorce consists in folding two canvases. In this case, the third remains in place. Designed for band saws for the processing of extremely hard material. In shape, every third tooth resembles a trapezoid. The location is the center of the canvas. With its help, the most correct direction of the saw band is carried out.

Sharpening recommendations

The principle of sharpening tape blades

If there are chipping on the tool, chipping will be observed on the edge of the workpiece. That is why it is imperative that sharpening is carried out correctly. During this process, it is necessary to work not only with the front, but also with the back of the canvas. Sharpening of devices can be carried out in different circles. In this case, it is necessary to take into account the angle of the canvas. If you want to carry out the procedure correctly, then you need to learn it from a specialist.

»How different is correct

How to understand if your saw is set correctly?

Divorce can be considered optimal when there is a mixture of 65-70% sawdust and 30-35% air between the saw blade and the tree that it cuts.

An outward manifestation of the fact that your saw is set correctly is that 80-85% of sawdust is thrown out of the cut.

In the event that you set the saw too far, there is a lot of air and insufficient removal of the amount of sawdust.

In the case of not before setting the saw, densely pressed hot sawdust remains on the surface of the board.

A saw that is too far apart will cut in jerky ways, but too far apart will cut in waves.

Another very important point: only the upper third of the tooth should be diluted, only a sharp corner at the very top of the tooth should participate in the sawing process.

Sharpen the saw with minimal metal removal (i.e. deburring) and then dilute.

If you have a problem with sawing, then read the 13 points below. it will help you.

Upon entering the log, the saw jumps up and cuts exactly to the end of the log, after which it falls down. This phenomenon is called squeezing. those. squeezes the saw. This is caused by too large a sharpening angle of the tooth. Reduce the sharpening angle by a couple of degrees.

When entering the log, the saw jumps upward and the board turns out to be curved like a saber. This is most likely due to the fact that the sharpening angle is too large, and the divorce is insufficient. Reduce the angle of sharpening of the tooth and increase the spread. The saw dives down and the board curves like a saber. This is caused by insufficient sharpening angle and insufficient setting at the same time. Increase the sharpening angle by a couple of degrees and increase the divorce.

Too much sawdust remains on the board and feels loose to the touch. Divorce is not enough, it should be increased. Reduce the sharpening angle.

Drank goes in a wave. If the saw is sharp, then this is due to too small a divorce, the divorce should be increased.

A dull saw that has never been sharpened will crack in the depressions of the tooth. This is because the blade is not sufficiently spread out for the work it is trying to do, or because the blade continues to be sawed after it has become dull.

The saw is cracked at the back. This is because the back stops of the guide rollers are too far from the back of the blade.

Sawdust is rolled onto the saw blade. This is due to the fact that the saw is not sufficiently spread and there is not enough air in the cut, the saw blade rubs against the sawdust, heats up and the wood dust is baked onto the saw. Increase divorce.

Sawdust rolls on the inner surface of the tooth, but this does not happen on the surface of the saw. This is due to poor quality of sharpening (too high feed or too much metal removal and, as a result, poor surface quality at the root of the tooth), or too large a sharpening angle of the tooth, or the fact that the saw blade continued to be sawed after it was already dull.

After sharpening, the blade becomes covered with cracks in the cavities of the teeth. During regrinding, too much metal was removed at a time, resulting in an overheated tooth surface.

Many problems are caused by the fact that the sharpening stone is not refueled often and accurately enough.

Do not forget that no matter how perfect the machine you use for sawing wood, it is just a device that pulls the saw through the log. The end result depends 90% on the correct maintenance of the saw and only 10% on the setting of the machine as a whole.

Remember to cut with an undivided saw. this is the fastest way to break it.

The sharpening angle is the angle of deviation of the end of the tooth from the vertical. The recommended sharpening angle for most cases is 10-12 degrees. For cutting hardwood and frozen wood, the sharpening angle is 8-10 degrees. For working with soft rocks 12-15 degrees.

Tooth set is an important factor in blade performance. Remember that when sharpening the teeth and decreasing their height, the setting also decreases.

Sharpening parameters of the band saw depending on the type of wood to be processed (given in the table).

Band saw tooth parameters.

Correct sharpening of band saws video

Sharpening and setting band saws

Saw band design

Band saw sharpening machine

Band saws are made of heavy-duty metal, which ensures not only high cutting quality, but also the saw’s durability. The teeth have a universal angle, which allows for the highest quality cutting of the material.

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Sources:

http://stroy-podskazka.ru/lentochnaya-pila/zatochka/
http://drevogid.com/instrumenty/pily/zatochka-lentochnoj.html
http://www.pilorama54.ru/pokupatelyam/lentochnye-pily/pravilniy_razvod_i_zatochka/
http://kak-sdelatpravilno.ru/kak-pravilno-raznoe/pravilnaja-zatochka-lentochnyh-pil-video.html

Electric Saws angle, band, correct, saws, sharpening