How To Correctly Set Up Your Bandsaw

How a band saw works

The operation of the saw should be checked and, if necessary, adjusted every time before performing a work task. Also, a check of the settings should be carried out after each possible contact of the saw support rollers with the body of the log.

The position of the saw in relation to the bed depends on the guide rollers of the installation. How correctly they are mounted can be checked using a special adjustment ruler. The surface of the rollers should not be left with residues of working, which can lead to unwanted vibration. The sides of the rollers should not have the characteristic risks that may arise when the rollers did not rotate during the operation of the sawmill.

In the course of setting up the band saw, the mandatory steps are:

  • Checking the bearings. When replacing them, you need to check the condition of the mounting fasteners in the roller housing for their integrity. If damaged, completely replace this part (roller).
  • Further, during the adjustment, you should check the fastening of the roller axis in the housing. This means that you need to make sure that all the studs securing the part are screwed in properly. If a backlash is found, then you need to replace the case. It should be noted that the joints between the guide carriage and the roller housing are often damaged during sawing. As a result, the position of the rollers cannot be precisely adjusted. Sometimes in such a situation, it helps to correct the bend with dismantling the roller housing. However, this is fraught with possible damage to the welding place. In such a situation, you need to replace the damaged part with a new one. Also applies to studs.
  • Be sure to adjust the rollers. This is necessary to ensure the same pressure of the rollers on the saw when the movable roller moves from one extreme point to another. Its guide should move in a plane parallel to the bed. If this action is not performed, then when the kerf widths change, the stiffness of the saw may change, which leads to the appearance of the so-called “wave”.

How to set up a band saw

To avoid the appearance of such a phenomenon as a “wave” during work on the sawmill, that is, the exit of a board with a wavy surface, which significantly reduces the quality of the output product, of course, it is necessary to correctly set the saw settings. To do this, you need to take into account the following factors:

  • correct setting of the sawmill;
  • control of work progress, in particular. cutting speed;
  • saw quality;
  • wood quality.

How to set up a band saw

When adjusting the saw for normal operation, after checking the adjustment of the perpendicularity of the vertical guides to the support table, you need to check the correct fit of the upper and lower rollers to the corresponding guides.

After that, do not forget to adjust the position of the saw on the pulleys and the installation of the sawmill itself for appropriate fastening. and do not forget to change the band saw blade in time.

The principle of the band saw

Before starting the work task, you need to check and, if necessary, adjust the operation of the machine. In addition, the settings should be checked after each interaction of the saw support rollers with the log body.

The position of the saw relative to the bed depends on the guide rollers of the installation. The correctness of the assembly can be checked using a special adjustment ruler. No machining residues should be left on the surface of the rollers, which could cause unwanted vibrations. The sides of the rollers should not present the inherent hazards that can arise if they do not rotate during sawmill operation.

When installing a band sawmill, there are three very important stages.

  • Checking the bearings. When replacing them, check the condition of the mounting brackets in the roller housing to ensure they are not damaged. If there is damage, then it is better to completely replace this part.
  • When adjusting, it is necessary to check the fastening of the roller axis in the housing. This means making sure that all the studs holding the part are screwed in correctly. If backlash is found, the housing must be replaced. It should be noted that the joints between the guide carriage and the wheel housing are often damaged when cutting. Therefore, the position of the wheels cannot be precisely adjusted. Sometimes it helps to correct the bend with dismantling the roller housing. But it can cause damage to the welding spot. Then you need to replace the damaged part with a new one. The same with hairpins.
  • Remember to adjust the idler wheels. This is necessary to ensure the same pressure on the saw when moving the movable roller from one extreme point to another. Its guide must move in a plane parallel to the bed. If this is not done, the stiffness of the saw may change as the kerf is changed, creating a so-called “wave”.
    correctly

How to set up a band saw

The band saw is an incredibly versatile tool. It can transform logs into planks, these planks into thinner planks, cut straight or curved mowing lines, and much more. However, you will need a suitable blade for the job; wider blades are best for straight cuts, narrower blades for tighter bends.

To exclude the appearance of such an effect as a “wave” during the sawing process, in other words, the exit of a board with an uneven, bumpy surface, you need to be able to correctly adjust the saw. To achieve the desired result, it is required to take into account such factors as:

  • correct setting of band sawmills;
  • control over the cutting process, including cutting speed;
  • the quality of the file;
  • selection of quality wood.

Saw band setup and installation

Adjustment plays an important role in the smooth and quality operation of the machine. Setting up a band sawmill includes: observing safety rules, adjusting, setting the blade, tensioning the blade, aligning the guides and aligning the table and stop. By following these steps, you will have a great tool to work with safely.

When setting the saw for normal operation, after checking the vertical rails to the support table and bearings are perpendicular, make sure the top and bottom rollers are correctly aligned with the rails.

Next, do not forget to correct the position of the saw on the pulleys and the setting of the sawmill itself for proper fastening. Remember to change the sanding belt in time. And remember that the tool heats up during the sawing process. The higher the cutting speed, the higher the heating temperature. Thus, the choice of cutting speed depends on the type of product (wood, metal), the size of the material and its density.

All about teeth and their corners

Band saws can have different tooth geometries, influenced by the type and properties of the raw material being cut. As for the tools for working with wood, they can be carpentry, dividing and intended for sawing logs. and the parameters and shape of the teeth for each “subspecies”, respectively, have their own. The sharpening angle of band saws for wood is determined by the manufacturer based on a number of factors, but this tendency is key. the harder the material, the smaller the rake angle should be.

Constant-pitch metal saws have two basic tooth shapes. standard and “positive rake”. Standard teeth for cutting thin-walled material, with positive rake for cutting thick-walled metal.

Now about the step size. For thin-walled workpieces (sheet metal, pipes), saws with a small tooth pitch are used. otherwise there is a risk of damaging or even breaking the tooth. Thick-walled materials are best handled with a tool with few taps per inch.

In order to eliminate the resonance effect that provokes vibrations of the blade, a number of saws are made with a variable pitch.

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 dressing the saw yourself, 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.

How to sharpen band saws correctly

Band saws are cutting tools used in band saws. They are a closed belt with teeth. They have a lot of their own, characteristic only for them, merits. Band saws leave the cutting width much smaller than circular tools: if this fact is perhaps insignificant when sawing budget wood, then when cutting elite metal and cutting valuable wood species it is critically important. With their help, you can cut absolutely any workpiece. In addition, band saws show good working speed. provide a high quality cut surface. Reducing chip waste due to their use is an obvious thing. However, in order to consistently feel in practice all the above advantages of working with the tool, it is necessary to take a responsible approach to its maintenance. Sharpening of band saws, as well as their distribution should be done efficiently and in a timely manner.

The price of sharpening band saws in specialized offices is usually low, but the speed and literacy of the work is not always pleasing. Can you handle the task yourself? Of course, if you know how to sharpen band saws correctly and have the necessary tools.

What errors can occur during the sharpening process?

Error 1. Burnt sinuses of the teeth of the product

The reason for this phenomenon lies in the excessive efforts of the grinding wheel. As a result, the tape becomes blunt quickly.

Error 2. Incorrect angle of inclination and imperfection of the shape of the sinuses of the teeth.

Several factors can lead to this situation:

demolition of the eccentric of the sharpening device;
error in setting the angle of inclination of the machine head;
inconsistency of the profile of the grinding wheel.

That’s all. Now you know how to sharpen a band saw correctly, and what tools and accessories may be required for this.

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.

The subtleties of the setting of band saws

As the tool is used, the quality of its cutting edge decreases. Therefore, setting and sharpening the band saws correctly is a natural part of the workflow.

Note! Divorce should be done before sharpening, not after!

Setting is the operation of bending the teeth to the sides to prevent the tool blade from jamming and reduce friction. There are three main types of wiring:

classic. the teeth are bent to the right and left of the side strictly alternately;
cleansing. every third tooth is left in its original position. “Relevant” for tools used for cutting especially hard materials and alloys;
wavy. each tooth has its “own” value of the bend size, thus a wave is formed from them. This is the most difficult type of wiring.

Worth knowing! When divorcing, not the entire tooth is bent, but only part of it. a third or two thirds from the top.

The divorce values ​​recommended by manufacturers fall within the range of 0.3-0.7 mm. The operation is carried out using a special adjustable tool kit.

Tips from professionals

In the case of sharpening the band saw with a machine, before starting work, you must make sure that the position of the sharpening disk relative to the tool is correct.
2. It is very important to remove such amount of metal from the sinuses so that all microcracks are guaranteed to be eliminated.
3. If the tool “functioned” without quality maintenance longer than the manufacturer admitted, the amount of metal removed in one sharpening should be increased.
4. Always use a new tool as a reference to check the sharpening results.
5. The shape of the saw tooth is a parameter developed and verified over the years. Therefore, it is a huge delusion to hope that the tool will cut like clockwork, regardless of what you do with the teeth.
6. Subject to operational requirements, the band saw will serve you conscientiously until its width is reduced to a figure equal to 65% of the original value. The width decreases, naturally, in the process of regrinding.
7. There is a completely absurd recommendation that there is no particular need for deburring after processing. If you “listen” to it, then the appearance of microcracks in the canvas is guaranteed.
8. After work, the band saw should be immediately cleaned of resin and sawdust, and thoroughly examined before sharpening. Otherwise, the risk of clogging of the grinding discs is extremely high. And this inevitably entails a “hack” sharpening procedure.

Tips from professionals

In the case of sharpening the band saw with a machine, before starting work, make sure that the position of the sharpening disk relative to the tool is correct.
2. It is very important to remove such amount of metal from the sinuses so that all microcracks are guaranteed to be eliminated.
3. If the tool “functioned” without quality maintenance longer than the manufacturer admitted, the amount of metal removed in one sharpening should be increased.
4. Always use a new tool as a reference to check the sharpening results.
5. The shape of the saw tooth is a parameter developed and verified over the years. Therefore, it is a huge delusion to hope that the tool will cut like clockwork, regardless of what you do with the teeth.
6. Subject to operational requirements, the band saw will serve you conscientiously until its width is reduced to a figure equal to 65% of the original value. The width decreases, naturally, in the process of regrinding.
7. There is a completely absurd recommendation that there is no particular need for deburring after processing. If you “listen” to it, then the appearance of microcracks in the canvas is guaranteed.
8. After work, the band saw should be immediately cleaned of resin and sawdust, and thoroughly examined before sharpening. Otherwise, the risk of clogging of the grinding discs is extremely high. And this inevitably entails a “hack” sharpening procedure.

All about teeth and their corners

Band saws can have different tooth geometries, influenced by the type and properties of the raw material being cut. As for the tools for working with wood, they can be carpentry, dividing and intended for sawing logs. and the parameters and shape of the teeth for each “subspecies”, respectively, have their own. The sharpening angle of band saws for wood is determined by the manufacturer based on a number of factors, but this tendency is key. the harder the material, the smaller the rake angle should be.

Constant-pitch metal saws have two basic tooth shapes. standard and “positive rake”. Standard teeth for cutting thin-walled material, with positive rake for cutting thick-walled metal.

Now about the step size. For thin-walled workpieces (sheet metal, pipes), saws with a small tooth pitch are used. otherwise there is a risk of damaging or even breaking the tooth. Thick-walled materials are best handled with a tool with few taps per inch.

In order to eliminate the resonance effect that provokes vibrations of the blade, a number of saws are made with a variable pitch.

Tools

Band saws are cutting tools used in band saws. They are a closed belt with teeth. They have a lot of their own, characteristic only for them, merits. Band saws leave the cutting width much smaller than circular tools: if this fact is perhaps insignificant when sawing budget wood, then when cutting elite metal and cutting valuable wood species it is critically important. With their help, you can cut absolutely any workpiece. In addition, band saws show good working speed. provide a high quality cut surface. Reducing chip waste due to their use is an obvious thing. However, in order to consistently feel in practice all the above advantages of working with the tool, it is necessary to take a responsible approach to its maintenance. Sharpening of band saws, as well as their distribution should be done efficiently and in a timely manner.

The price of sharpening band saws in specialized offices is usually low, but the speed and literacy of the work is not always pleasing. Can you handle the task yourself? Of course, if you know how to sharpen band saws correctly and have the necessary tools.

How to sharpen a band saw correctly?

It has been proven that over 80% of tool breaks occur due to non-compliance with the rules for sharpening band saws. The need for manipulation is determined visually. by the appearance of the teeth themselves or the condition of the cut walls (an increase in surface roughness).
Wheels for sharpening band saws are chosen depending on the hardness of the teeth. For sharpening tools made of tool steel, turn to corundum wheels. Bimetallic saws require diamond or borazon samples. The shape of the grinding wheel for band saws should be determined based on the parameters of the tool. It can be profile, cup, flat, disc-shaped.

Before starting work, it is recommended to let the saw hang in the inverted state for ten to twelve hours.

Requirements for sharpening band saws with your own hands:

ensuring uniform metal removal along the tooth profile;
elimination of excessive pressing of the circle (this can lead to annealing);
ensuring the preservation of the height and profile of the tooth;
mandatory presence of coolant;
control of the absence of burrs.

The standard instruction for sharpening band saws states that sharpening should be done either on the front surface of the tooth, or on both the front and back. But this is theory. In practice, many professionals, and even folk craftsmen, “perform” it exclusively on the back surface. so, in their opinion, it is more convenient.

In general, despite a lot of rules and requirements, these tools are quite unpretentious in terms of sharpening. You can work with them both with the help of a special sharpening device for band saws, and manually; apply for processing circles of different shape and material, etc.

Before sharpening a band saw, you need to familiarize yourself with the main methods of performing this operation.

Full profile sharpening

It is of the highest quality and is produced on an automatic machine. An elbor circle, precisely matched to the shape, goes through the entire interdental cavity in one stroke, together with the corresponding surfaces of adjacent teeth. Obtaining angular shapes at the base of the teeth is thus excluded. The only drawback of such a sharpening is the need to have a certain number of circles for “multi-profile” saws at constant disposal.

Sharpening the edges of the teeth

Can be carried out on a professional machine or manually.
If the preference is given to the machine, then you should, again, choose the circle correctly. usually these are flat samples. In general, it is recommended to turn to specialized sharpening equipment only in cases where the volume of work is large enough. Occasional “home” manipulations are best done manually. with the help of an engraver or on a conventional machine. When working for safety reasons, it is imperative to use a mask or goggles.

If there is neither a machine tool nor an engraver in your arsenal, then you can sharpen a band saw using the usual old-fashioned method. wielding a file. Three or four confident movements along the back or front edge of each of the teeth. and the case, as they say, is “in the bag.” With regular and diligent execution of the operation, the skill of high-quality manual sharpening will appear quickly.

The subtleties of the setting of band saws

As the tool is used, the quality of its cutting edge decreases. Therefore, setting and sharpening the band saws correctly is a natural part of the workflow.

Note! Divorce should be done before sharpening, not after!

Setting is the operation of bending the teeth to the sides to prevent the tool blade from jamming and reduce friction. There are three main types of wiring:

classic. the teeth are bent to the right and left of the side strictly alternately;
cleansing. every third tooth is left in its original position. “Relevant” for tools used for cutting especially hard materials and alloys;
wavy. each tooth has its “own” value of the bend size, thus a wave is formed from them. This is the most difficult type of wiring.

Worth knowing! When divorcing, not the entire tooth is bent, but only part of it. a third or two thirds from the top.

The divorce values ​​recommended by manufacturers fall within the range of 0.3-0.7 mm. The operation is carried out using a special adjustable tool kit.

  • A little theory: what the tool is made of?
  • All about teeth and their corners
  • The subtleties of the setting of band saws
  • How to sharpen a band saw correctly?
  • Professional advice
  • What errors can occur during the sharpening process?

A little theory: what the tool is made of?

Saws for wood are usually made from tool steel (hardness 45 HRC).
For the production of metal products, Russian manufacturers turn to V2F and 9HF steels, while foreign ones. to C 75, etc. The teeth of such saws in the process of hardening by high-frequency currents are “rewarded” with the highest hardness. Often, when working with metal, a bimetallic band tool is used: its blade is made of spring steel, and the band with teeth is made of an alloy with high m cobalt and tungsten. This high speed steel “attaches” to the base of the saw using an electron beam.

What errors can occur during the sharpening process?

Error 1. Burnt sinuses of the teeth of the product

The reason for this phenomenon lies in the excessive efforts of the grinding wheel. As a result. rapid blunting of the tape.

Error 2. Incorrect angle of inclination and imperfection of the shape of the sinuses of the teeth.

Several factors can lead to this situation:

demolition of the eccentric of the sharpening device;
error in setting the angle of inclination of the machine head;
inconsistency of the profile of the grinding wheel.

That’s all. Now you know how to sharpen a band saw correctly, and what tools and accessories may be required for this.

How to set up a band saw correctly

Smart band tension. an important factor affecting the quality of the cut and the service life of the saw. The band saws are tensioned according to the selected type of saw blade, therefore, when installing it, always follow the manufacturer’s recommendations. After attaching the saw band, slightly tighten it so that it does not fall off the wheels; fasten the bolts to the saw band; tension the saw blade until it is at the recommended value.

Saw band stroke control

Next, you need to check the progress of the band saw on the guide “cubes” and wheels. It is necessary to turn on and after 10 seconds turn off the saw drive. If the saw band drive cannot be switched on, the saw band tension limit switch must be adjusted. Turn off the main switch. Make sure that the saw blade is properly seated on the guides. Open the guards and check the position of the saw blade on both wheels. If the distance between the rear part of the belt and the shoulder of the wheels is 1. 2 mm, then the installation is correct. If the distance is more than 1. 2 mm, or the band is moving along the shoulder of the wheel, then the band must adjust the blade stroke on the band saw. Then it is necessary to close the guards of the saw band.

Installing the saw band support rollers
The installation of hard metal support rollers is one of the criteria that affects the accuracy of the cut and the service life of the saw blade. For this reason, it is necessary to regularly check the condition of the support rollers and their correct setting. Tighten the adjusting screw on the back of the cube guide so that the saw blade does not move. Loosen the screw and at the same time check with your hand that the guides are not creating too much resistance when the saw band moves. As soon as the saw band starts to move freely and without resistance, it means that the hard metal support rollers are correctly adjusted. Make sure that the support rollers do not create too much resistance when the saw blade moves. Otherwise, the service life of the saw band and motor drive will begin to decrease.

The specialists of the metalworking department of the “KronDe” company are always ready to advise you on the installation of band saw rollers, control of the band saw and other aspects of the maintenance of band saws, press brakes, hydraulic guillotine shears and hydraulic profile benders.
For all questions you are interested in, you can contact us by phone:
Moscow (495) 662-94-23 | St. Petersburg (812) 612-05-56

Installation of guiding “cubes”
The service life of the saw blade and the quality of the cut largely depend on the correct setting of the “cubes” guides. Therefore, their setting should be checked regularly. Loosen both guide rail mounting screws and gently press them against the top edge of the tape. At the same time, make sure that the tape does not bend, otherwise the guide “cube” will press on the tape and damage it. Tighten the fixing screws again. If the “cube” guide is set correctly, its top edge and ruler will be parallel.

Saw band stroke adjustment
The installation of the belt on the impeller and in the guide “cubes” must be checked regularly. When changing the saw band, it is especially important to correctly set the path of the saw band.

Blade travel control
If the belt path is set incorrectly, problems can arise such as: the saw blade coming off the impellers and, as a result, damage to the saw blade and the guard; the running of the band saw along the ledge of the idler wheel. this could damage the bar and wheel shoulder. In such situations, it is necessary:

  • Switch on and after a short time switch off the saw drive.
  • Turn off the main switch.
  • Open the cover.
  • Check the installation of the belt on the impellers.

If the distance between the rear part of the belt and the shoulder of the wheels is 1. 2 mm, then the installation is correct. If it exceeds 1. 2 mm, or the band moves along the shoulder of the wheel, it is necessary to adjust the path of the saw blade.

Adjusting the Saw Blade Travel

  • The saw band stroke is adjusted using a hex screw in the tension “cube”.
  • The required distance between the back of the belt and the shoulder of the wheel is 1 mm.
  • Turning the screw to the right brings the tape closer to the shoulder of the idler wheel.
  • If you turn the screw to the left, the tape will move away from the shoulder of the idler wheel.
  • After all the settings, you need to check the tape run again.

Brush installation
The brush affects the performance and accuracy of cutting, the service life of the saw band, impellers, and support roller made of hard metals. For this reason, the brush must be monitored during every shift. Make sure that the ends of the brush bristles do not touch the bottom of the saw blade teeth.

How to sharpen a band saw to cut up to 100 cubic meters!

Entirely and immediately

If you carefully read how the work is going in the first way, you should have understood how difficult it is really to sharpen the saw with high quality.

There is constant talk that it is impossible to cut quickly and well with narrow band saws. Saws break quickly. It is almost impossible to find a sharpener to prepare them correctly. The exit lumber produces a large wave, which negates all the benefits of a thin cut.

So, in order to radically solve all these problems at once, Wood-Mizer proposed a method of not sequentially grinding each tooth of a band saw, but at once the entire tooth profile with just one entry of a special profile disc into it.

In this way, three main problems are solved at once:

  • There is no need to look for a highly qualified sharpener. almost any person can sharpen a saw in one pass with factory quality on such a machine. He only needs to bring the blade to the saw. The machine will do the rest by itself, which makes it possible to maximally exclude the influence of the human factor on the quality of the result. 1 mm. Further sharpening goes as usual.
  • Band saws work two to three times longer, since the saw along the entire length is obtained with a completely grooved and absolutely identical profile of each tooth without burns, microroughnesses and scratches, that is, without stress points.
  • The sawmill can work at its maximum performance, since the saw along the entire length is obtained with the same front and rear angles on each tooth. But, despite all the advantages listed, this method of sharpening was practically not used for a long time on sawmills.

This happened for the following main reasons:

  • Very high price. Therefore, such a machine was bought mainly by service centers.
  • Not very convenient technical solutions for the sharpening process itself. A warm room was required, a special oil, only with which a weak oil pump could work. With intensive sharpening, this oil began to burn, so a mandatory hood was required and much more.
  • But the biggest limitation was the inability to sharpen the profiles of band saws other than Wood-Mizer, manufacturers, since Wood-Mizer made profile blades only for their saws. There were no other manufacturers of borazon grinding discs then.

Cheap group. Some manufacturers of classic grinding machines simply change the phases of movement on the cam. Now the disc no longer moves along the tooth, but only up and down. This gave them the opportunity to sharpen the entire tooth at once when installing a profile disc. But none of them understood that to sharpen the saw with a profile disc, it is necessary not only to change the phases of the cam movement, but also to make the entire machine according to a different class of accuracy. This has already caught many of those who turned to us for help. Therefore, I want to warn you right away about the pointlessness of purchasing such machines. The worst thing for a disc is machine backlash. If they are (and they are on all ordinary sharpening machines and, accordingly, remain on those sharpening machines that simply, with the help of another cam, try to remake them for working with CBN discs), then the disc begins to unpredictably hit either the front edge or the rear, and, accordingly, break the profiles of the saw teeth. Then, the already sharp tips of the teeth begin to cut the disc, several times reducing its service life.

Backlash can ruin the disc after 500 m. This is what happens with those who have already purchased such machines. At first, sharpening goes well, but very quickly an expensive grinding wheel becomes inoperative (it simply cuts off the front part to the base or cuts through the risk). You need to buy a new disk, which is already becoming economically unprofitable.

In fig. 3 shows the phases of motion of the profile disk. It should fit into the profile of the tooth all at once and sharpen with the entire plane. The thickness of the applied elbor layer is only 0.25 mm. But this layer is quite enough for long normal work. If the front part of the disc, when entering the profile, cuts into the apex of the tooth (Fig. 4), then the sharp cutting edges of the teeth puncture the risk relatively quickly in the coating or even tear it off in this place completely to the base, making the disc inoperative. In this case, there is also a breakdown of the tooth profile.

Dear group. These are the manufacturers who simply copied the Woodmizer machine. At the same time, they obtained the machine at the price of the original, and the workmanship is the same or even worse. With this option, it seems to me, it is better to purchase a verified original. However, it’s up to you to decide.

A machine for sharpening band saws with a borazon full-profile circle. This machine stands for sharpening in our service center.

Sharpening in this way is especially relevant when the saw is working on band-dividing machines, since the saw there, unlike the sawmills, works all the time, without stopping, and any untouched stress points there affect much faster.

However, this method of sharpening is now already economically profitable when preparing a band saw even on one sawmill.

Here is a rough economic payback calculation provided to us by the owner of one of the sawmills.

  • The sharpener’s salary is about 10-15 thousand rubles a month. It takes a full day to prepare 10 band saws per shift.
  • Small saw resource. sawing about 15-25 m 3 round timber into edged lumber.
  • With a poor or average quality of saw preparation, the productivity of a sawmill for cutting wood into edged sawn timber is usually 0.2-0.5 m 3 per hour of round timber, that is, about 100 m 3 of round timber per month.
  • On average, five band saws are consumed per month. With an average price of a saw of 800 rubles, the cost of them will be 4000 rubles.
  • The average cut of 20 m 3 is multiplied by the number of saws (5 pcs.), We get 100 m 3.
  • Let’s take the average profit received from 1 m 3 of edged lumber equal to 400 rubles, with an average or poor surface quality and, accordingly, not the highest price for lumber.

Profit for the month will be 400 × 100 = 40 thousand rubles.

Total: net profit for the month will be 26 thousand rubles per month: 40 thousand rubles. 10 thousand rubles (sharpener salary). 4 thousand rubles (cost of saws).

And how much nerves it will cost, only you know!

  • It takes 60-90 minutes to prepare 10 band saws per shift. No additional person required. Saws can be easily prepared by the owner of the sawmill or the frame operator.
  • Saw resource. sawing approximately 40-60 m 3 or more of round timber into edged sawn timber.
  • The productivity of a sawmill for cutting wood into edged sawn timber is usually 0.8-1 m 3 per hour of round timber, that is, approximately 200 m 3 of round timber per month.
  • On average, five band saws are consumed per month. With an average price of a saw of 800 rubles, the cost of them will be 4000 rubles.
  • Let’s take the average profit from 1 m 3 of edged lumber equal to 450 rubles, with good surface quality and, accordingly, a high price for lumber.

Profit for the month will be 450 x x 200 = 90 thousand rubles.

Total: the net profit for the month will be 86 thousand rubles: 90 thousand rubles. 4 thousand rubles (the cost of saws).

With quiet production!

We get the difference in profit for the month: 86 thousand rubles. 26 thousand rubles = 60 thousand rubles.

The difference in the price of the machines: 75 thousand rubles. 25 thousand rubles = 40 thousand rubles.

Thus, already in the first month of work, you pay off the grinding machine with a profile wheel and then only increase your profit.

The calculation was made approximately. But it relies on real work experience. You can do your specific calculation yourself.

Sharpening method in which the bands are cut 2 times more lumber!

In previous publications, we began a conversation about the specifics of the acquisition and subsequent operation of sawmills, band-dividing machines for the production of moldings and band-sawing machines for furniture enterprises. We dwelt in detail on the consideration of the classical method in which the teeth are sharpened with a grinding wheel. And they reflected two factors that affect the quality of sharpening. technical and instrumental. The third factor, the last on the list, but essentially the main one, is the human factor.

When choosing a person to work as a sharpener, first of all pay attention to his character. Hot, explosive, trying to do everything quickly, a person will never become a good sharpener. Here you need a calm, attentive, diligent, responsible person who can perform monotonous work for a long time. But even this is not enough. Good sharpeners are obtained only from those who can literally feel the saw and adjust the sharpening machine only by ear. It is not for nothing that the people say that one must be born a good sharpener. And indeed it is. Since it is practically impossible to simply sharpen the band saw in this way mechanically, for the reasons indicated above and below.

Now we will show what exactly the sharpener needs to do in the process of work.

The sharpening process must begin with an inspection of the machine:

  • It is necessary to check the alignment of the grinding wheel and the plane of the band saw so that they are strictly perpendicular. Otherwise, the tooth will be sharpened with a bevel to the side.
  • Set the grinding wheel to the desired angle in relation to the plane of the saw, that is, set the rake angle of the tooth along the limbs of your machine. Since these dials never correspond to reality, after sharpening the saw, check the obtained real angle with a protractor. If it does not suit you, slightly change the angle setting in the required direction. Sharpen the saw again and check the resulting angle. And so on until you get the required angle. It is advisable to do this with a circle with great hardness, so that during installation the circle does not lose its shape. Otherwise, you will have to edit it and thereby knock down the presets. After you get the desired angle on the saw, make a scribble note on the machine. It will be useful to you later for new reinstallations at other angles.
  • All moving parts must have minimal backlash, and it is better that there are no backlashes at all, otherwise the profile of the teeth and the grinding wheel will break rapidly.
  • The coolant must be supplied in such a way that the entire sharpened tooth is washed, otherwise the part of the tooth where the liquid does not enter will be set on fire.
  • The grinding wheel must be set to the correct size and sufficient hardness so that its profile does not change at least one full pass, otherwise the saw will have a different tooth profile along its entire length.
  • During sharpening, you cannot change the adjustments of the grinding wheel until a full pass has been machined, otherwise a different profile will turn out at the transition points and during subsequent passes the wheel will either burn the profile or pass without touching it.

The grinding wheel is adjusted with two screws:

  • a pusher screw that regulates the cutting along the leading edge and the passage of the tooth profile;
  • plunge screw.

After preparing the sharpening wheel, set the band saw and, by scrolling the wheel by hand or at minimum feed, check how accurately it follows the profile. Profile the circle again if necessary.

After finishing work, it is necessary to clean the saw clamping mechanism, the coolant tray from dirt, metal filings and rust; check the fluid level and add it if necessary; wipe the whole machine.

The main reason for incorrect sharpening of the band saw is the loss of its shape by the sharpening wheel.

If a technical problem can be solved with the help of high-quality manufacturing of the machine itself (for example, Vollmer produces very good machines), if the tool problem can somehow be solved by the correct selection of the grinding wheel, then the problem of forming the profile of the grinding wheel cannot be well solved even theoretically.

Only very experienced sharpeners or people with an inner instinct can come close to understanding and maximizing the accuracy of profiling the end of the grinding wheel. Let me explain this with an example. Draw a horizontal line on a piece of paper. Now, from this mowing line to the right side by eye, draw two vertical mowing lines: one at an angle of 10 °, and the other after 3 mm at an angle of 40 °. Now connect the left line to the horizontal line through a 1.5mm radius and the right line through a 1-2mm radius. Do this several times and check with the protractor what you get. For clarity, you can combine these sheets. Please note that a data discrepancy of only 0.5 ° already leads to inaccurate profile cutting. And inaccurate connection of the left straight line also leads to a change in the saw pitch. Now imagine that the sharpener should do all this not on paper, but on a rotating circle, where it is even more difficult to maintain exact dimensions. But it is not enough to form it once. It is necessary that when re-sharpening after sawing, the profile of the end of the wheel is exactly the same as in the previous sharpening, which is practically impossible. Therefore, it is not so important what quality around you are sharpening. Even if you have a very good circle and you can grind a set of band saws for a whole shift with it without additional profiling, you will almost never be able to repeat exactly the same profile of the wheel end the next time you sharpen, which means you will not be able to accurately grind the profile of the saw teeth after its bluntness. Now you understand why the exact formation of the end face of the profile of the circle is not only difficult, but extremely difficult. In order to somehow facilitate its solution, you can sharpen with bakelite reinforced circles 3-4 mm thick. But it is difficult to find them of the required workmanship.

Therefore, the profile of the circle must be monitored very carefully. Otherwise it leads to the following changes in the band saw body:

  • A change in the radius at the base of the tooth, which entails a change in the step and the impossibility of normal sharpening of the saw already on the next pass. The circle begins to cut unevenly into the front edge without touching the back, or vice versa, that is, it becomes impossible to grind the full saw profile at once. Already in two or three passes, the sharpener tries to grind at least the cutting edges of the teeth, while a microhump or micro depression appears at the transition point, which leads to the appearance of microcracks, and microcracks that have already arisen during sawing are not removed, which leads to premature rupture of the saw along the body.
  • Changes in sharpening angle, tooth height, cavity shape, which affect the performance of the sawmill and the quality of the resulting sawn timber.

The grinding wheel should look as shown in fig. 1a. Thickness. 5-8 mm. But in practice, working with such a profile is very difficult. We recommend using circles with a profile as in fig. 1b. Thickness. 3-4 mm. Then the sharpener will not need to very often form the profile of the grinding wheel, but only occasionally slightly correct it. This greatly simplifies the work of the sharpener.

As will be shown below, only 3-4 mm of grinding wheel thickness can be involved in the sharpening process. thickness is only needed if you have the perfect machine. But this does not exist in nature. And also if you want to sharpen at accelerated tooth feeds, then the circle will not bend and bend. But at the same time, you are almost guaranteed to get large risks and burns and thereby greatly shorten the life of the saw, and you can hardly cut well. The cutting time of one whole pass of a 4 m band saw should be 10-15 minutes. At least two passes are needed: the first is sharpening, the second is finishing to remove the marks.

In practice, it is rarely possible to sharpen a saw well in one pass. often, two or three are needed. So, if now the sharpener tells you that he will bring a sharpened saw in 15 minutes, you can imagine what quality it will be.

Possible violations of the shape of the end of the grinding wheel and the resulting profile of the saw tooth are shown in Fig. 2.

Under numbers 1-7, the red dotted line shows the exemplary profile, the solid line. the resulting.

How to Setup and Resaw on the Bandsaw with @WobyDesign

  • Correct end shape. ideal for the resulting tooth profile.
  • Sewing while sharpening the front radius. There is a change in the radius of the root, followed by a change in the pitch of the saw.
  • Left side radius too small or missing. During sharpening, the front tooth radius is not formed. This leads to a change in the saw pitch, as well as to an increase in stress during sawing at the root of the tooth, which leads to the occurrence of micro cracks and accelerated rupture of the band saw in this place. This shape of the end of the circle can be obtained during the initial formation or in the process of sharpening.
  • Incorrect preparation of the right side. Filmed too little. During sharpening, the cavity will increase, the tooth will be shortened and set on fire at the exit. This state of the grinding wheel can also occur during the sharpening process.
  • Incorrect preparation of the right side. Too much filmed. During sharpening, the stroke of the grinding wheel will be less than the cavity, that is, the back of the tooth will not be sharpened.
  • Incorrect preparation of the right side. the angle is greater than the posterior angle of the tooth. During sharpening, the rear part of the cavity will not be ground, since the right end of the circle will abut faster against the back of the tooth than the right radius will reach it. The tooth will be shortened and ignited at the exit.
  • and. Incorrect preparation of the right side. the specified angle is less than the posterior angle of the tooth. The circle follows the profile of the tooth almost exactly.

As you can see from the examples above, it is almost impossible to ideally prepare a grinding wheel due to problems with the right side. Therefore, you must try to shape the working surface as shown in paragraph 7a. The circle of the required hardness with such a profile will allow the sharpener to grind several band saws before straightening, the number of which depends on the thickness of the material being removed. But at the same time, you still need to follow the work of the circle, since as the end of the circle is grinded, the angle of the right side will increase and the circle must be re-profiled.

If you immediately put a circle with a thickness of 3-4 mm (paragraph 7.b), you will practically not need to profile the right side, you only need to follow the left side, and this greatly simplifies the process of forming the end profile.

It is also necessary to remove such an amount of metal in one pass so that there is no cauterization of the body or the cutting edge of the band saw. Sometimes even with a small removal of the metal, blackness still appears. In this case, it is necessary to clean the grinding wheel with a straightening pencil from the adhered metal particles and grind the saw again.

You can not leave also big risks, you must go through another circle and grind them.

So, it is imperative to give the end of the grinding wheel the correct shape and sharpen the band saw only along the entire tooth profile, using a harder wheel, remove as little metal as possible in one pass so that no burns occur, sharpen the saw in several passes, so that in the end barely noticeable white risks remained. The tooth profile should be the same along the entire length of the saw and match the sample.

The saw must be installed in a clean and stainless steel machine. Otherwise, the push rod may not have enough force to pull the saw and the grinding wheel will hit the tooth. The tooth will be damaged. The wheel can also split if it cuts hard.

The saw band must be tightened all the time when sharpening, and the tightening mechanism must be clean. The clamping force should be such that the pusher pushes the tooth with slight tension, but so that the engine does not slow down. If the saw is loosely clamped, it can move backward behind the outgoing pusher or forward from the force of the grinding wheel. The result will be the same as in the previous paragraph.

If there is any doubt about your sharpener’s ability to sharpen the band saw correctly, you can test it for a few minutes.

You need to take any saw, prepared for work, and look at it from above the tooth, where the grinding wheel passed. The end should be the same silver color. If the cavity is darker in color, then it has not been pierced. There should be no blackness at the end. If there is blackness, then when working in the body, microcracks rapidly appear in these places, which leads to a rupture of the band saw. over, the cutting edge should not be set on fire, since in this case it will instantly become dull and the saw will stop cutting, that is, a wave will go. Only barely visible white risks are allowed.

You also need to check the shape of the tooth using the sample, which should be at the sharpener. Such a piece of tape can always be obtained from the company from which you purchased the tape.

If you are already tired of reading how to sharpen correctly in the first way, and you just want to work and make a profit, without constantly thinking about all these problems, then only the second way of sharpening a band saw is suitable for you.

Sharpening discs

Sometimes there is confusion about how borazon differs from elbor.

Borazon. technical cubic boron nitride (b-BN). was first obtained in 1957. In 1969, General Electric registered the Borazon trademark for a crystal.

Elbor is technical cubic boron nitride (b-BN). Elbor was synthesized in 1959 by a team of scientists from the Institute for High Pressure Physics (IHPP) of the USSR Academy of Sciences. Since 1964 industrial production of Elbor and tools from it has been organized.

Thus, it is one and the same material, but obtained in different ways in different countries. It is believed that Russian elbor has the best grinding properties in its structure.

To date, working with disks from different companies, we have received an average resource:

  • Wood-Mizer. ≈5-7 km;
  • Polish, Turkish and other unknowns. ≈2-4 km;
  • Russian-Ukrainian production. 7-10 km and more.

I want to repeat what I started this article with. Any machine tools are bought to make a profit with their help. Everyone wants to supply equipment and work without unnecessary problems. But rarely does anyone really know what they will have to face after installing the main equipment. After reading this article, you have a complete understanding of all the pros and cons of the two ways to sharpen a band saw. Now, based on this knowledge, you can already make the right choice on your own.

We offer you to purchase a trial batch of band saws with subsequent sharpening in our service center, this will give you an understanding of how band saws work after sharpening with a borazon wheel, compare them with your sharpening and not buy a seemingly expensive and modern machine.

Influence of the material and shape of the workpiece on the band saw settings

The grade of material and the shape of the workpieces to be processed, as well as the quality of the workpiece material, makes its own adjustments when preparing the equipment for work.

When setting up a bimetallic band saw for metal for cutting hard-to-machine metals and alloys, you need to be prepared that the durability of the saws may decrease several times, or the tool will fail almost immediately. In this case, it is advisable to use carbide saws.

In addition, the resource of the tool significantly reduces the presence of sand, shells, inhomogeneous hardness in the structure of the workpiece, as well as the presence of scale on the surface of the workpieces.

When sawing packages of workpieces, it is necessary to ensure the reliability of its fastening in the clamping device of the machine, since turning at least one workpiece in the package leads to chipping of the cutting edges of the saw teeth and its premature failure.

When cutting thin-walled pipes and profiles, uneven and shock loads act on the cutting edges of the teeth due to the fact that initially a solid part of the workpiece is cut (for example, near a pipe), and then the cutting zone is shifted to thin walls. Because of this, there is an increase in the vibration component of cutting and, as a consequence, micro-chipping of the cutting edges of the teeth. In this regard, there is a drop in the expected tool life to 50-60%. All this must be taken into account when making adjustments to the saw band.

Band saw for metal and coolant

The quality and concentration of the used cutting fluid (coolant) significantly affects the service life of the saw band. The coolant must have the concentration recommended for the processed material grade. It should be a high-quality synthetic or semi-synthetic water-soluble oil-based emulsion, which must be changed 1-2 times a year, as well as flush the entire supply system.

When setting up a band saw for metal to work, it is necessary to provide an abundant supply of coolant to the cutting zone. The use of low-quality cutting fluid can reduce the durability of the saw blade by 10-20%.

Setting up a band saw for metal

A properly made metal band saw setting will increase the tool life during continuous operation. In band sawing, the durability of the band saw blade (saw) is assessed by the total amount of cut material (m2), but most often. by the amount of material per one meter of the saw blade running (m2 / linear m), as well as by the number of cut pieces (pcs; cuts).

As a rule, incorrect settings of the band saw machine and the blade in particular are the main reasons for the failure of band saws are, among which are:

  • destruction of saw teeth on a section of the blade with a length of more than 100 mm;
  • saw blade break anywhere;
  • deviation from the straightness of the cut (“drift”) due to wear of the cutting edges of the teeth;
  • wear or wrinkling of the back of the saw blade.

Enterprises justifiably try to minimize financial costs for production support, this also applies to purchased cutting tools. In this regard, such a requirement is imposed on band saws as the maximum possible service life with minimal financial costs. One of the tasks of technical specialists and maintenance personnel is to ensure that all the necessary requirements are met and observed so that this condition is met, that is, to ensure the maximum possible service life of the band saw blade and at the same time maintain the required productivity and technology. It is to achieve this goal that precise adjustment of the band saw for metal is required.

Adjustment of band saws in order to increase their durability largely depends on the combination of the following factors.

Design features of a tape saw with general settings

The design features of the band saw equipment are of great importance when adjusting the band saw for work.

For the main series production, industrial high-performance machines with a rigid two-column structure and feedback devices are required. For small and auxiliary industries, simplified two-column machines or machines with a cantilever saw frame are suitable. Blade width is an important factor in increasing band sawing capabilities, tool life, productivity and power (cutting capacity).

The influence of the technical condition of the machine on the settings of the band saw

The technical condition of the band saw and its individual units (tension unit, pulleys and bearings, carbide and roller guides, uniformity and smoothness of the saw frame lowering) are of great importance when adjusting the band saw for metal.

It is necessary to periodically monitor and check the tension force of the band using a tensometer. Depending on the width of the web, it should be within 140. 300 N / mm² (1400. 3000 kgf / cm²). For canvases measuring 13×0.65 and 20×0.9. 1400.2000 kgf / cm²; for canvases measuring 27×0.9 and 34×1.1. 1800.2500 kgf / cm²; and for canvases measuring 41×1.3. 80×1.6. 2100.3000 kgf / cm². This will prevent premature saw failure.

The pulleys should be in the same plane parallel to each other, have no runout and be regularly cleaned of chips.

The gap between the carbide guide plates and the saw blade must be adjusted according to the machine data sheet.

The saw frame must be rigidly fixed to the bed and move smoothly along the machine guides without jerks and “dips”.

Adjustment and control of the above parameters will prolong the operation of the equipment and the belt.

Setting the cutting modes of the saw band

When preparing a band saw for operation, it is important to select the exact parameters of cutting modes: cutting speed (m / min) and productivity (cm² / min). Here it should be borne in mind that for each group of materials and standard sizes of workpieces in the reference data of each manufacturer of tape blades, there are recommended settings for the range of cutting data. Taking the minimum values ​​of the range, we obtain the greatest durability of the saw blade, but low productivity, and vice versa, if the setting of the band saw for metal assumes maximum cutting conditions, then the output will be high productivity, but lower tool life.

For example, for Eberle bimetallic saws, when cutting a round workpiece Ø 100 mm made of 45 steel, the following cutting data settings are recommended:

  • cutting speed: V = 65.75 m / min;
  • productivity: Q = 41.67 cm² / min.

To ensure the greatest durability of the saw, we accept the lower values ​​of the range: V = 65 m / min; Q = 41 cm² / min. (the cutting time will be 1.9 minutes). To increase the cutting performance, we use the highest value: V = 75 m / min; Q = 67 cm² / min (cutting time 1.2 minutes).

Choice of tape

The correct choice of the parameters of the band saw blade (standard sizes, material, brand, tooth shape, tooth pitch), depending on the shape and material of the cut blanks, is also of great importance in preparing the machine for operation and setting the band saw.

The pitch of the saw blade teeth must correspond to the dimensions of the workpiece (package of workpieces), and the shape of the saw teeth must correspond to the brand of the processed material. For example, for metals that form short chips, brittle materials from high-carbon steels, tool steels and cast irons, thin-walled profiles, saws with a standard “N” tooth should be used, which has a rake angle of 0 °, and for solid viscous materials that give elongated chips, iron-containing metals and alloys, saws should be used that have a positive rake angle of 12-15 °, the so-called “CS” hook tooth. This is due to the fact that these materials are prone to work hardening.

For cutting hard-to-cut, heat-resistant, stainless, titanium and nickel alloys, it is advisable to use carbide band saws (with carbide brazed plates on the teeth). This will increase durability and productivity by at least 3-5 times.

Installation of a band sawmill.

This is especially important in cases where the support legs of the sawmill are not secured with anchor bolts, as recommended in the machine’s operating instructions. All supporting feet must touch the floor without any gaps. If a gap is found, it must be eliminated.

Bed rollers.

After adjusting the perpendicularity of the vertical guides to the bed, it is necessary to check the fit of the upper and lower rollers to the corresponding guides. The lower pressure rollers (if any) are also adjusted if necessary.

Setting up the band sawmill.

The setting of the band sawmill should be checked daily, and always after possible contacts of the saw support rollers with the log. Saw guide rollers determine the position of the saw relative to the machine support table. The correctness of their installation is controlled using an adjustment ruler. The rollers themselves should not have traces of wear on the working surface. this leads to vibration of the saw. There should be no deep marks on the sides of the rollers (they are obtained if the rollers did not rotate when the saw was moving). The condition of the bearings is also checked. If the bearings are being replaced, it is necessary to check the condition of the bore holes in the roller housing. they must not be broken. In this case, replace the roller assembly.

Next, the fastening of the roller axis (pin) in the housing is checked. If any backlash is detected (all pins securing the axle are tightened), the body is replaced. Often during operation, the place of attachment of the roller body to the carriage guide is damaged, therefore it is not possible to correctly adjust the position of the rollers (there is no adjustment margin). You can try to straighten the bend by first removing the roller housing. True, this can damage the weld spot, so it is better to replace the defective body with a new one. Broken adjusting pins and rolled locknuts should be replaced immediately with new ones.

After replacing defective units and parts, the saw rollers are completely adjusted. To ensure uniform pressure of the rollers on the saw when moving the movable roller from one extreme position to another, the guide of the movable roller must move in a plane parallel to the plane of the support table. Without such adjustment, when the width of the cut changes, the stiffness of the saw blade changes, and this provokes the appearance of a “wave”.

Please note: there should not be even a slight backlash in the drive unit of the guide roller.

What to do if a “wave” occurs during sawing?

Sometimes, when sawing, an uneven, wavy surface of the board appears, which naturally reduces the quality of the product.

To get rid of the problem, we advise you to pay attention to the following factors:

  • correct adjustment of the band sawmill
  • cutting speed
  • saw quality
  • wood quality

Adjusting the position of the saw on the working pulleys.

The long run of the saw from the pulleys will stretch the trailing edge, and as a result, the saw becomes unstable in the cut. In this case, the defect does not appear immediately, sometimes after the second or third sharpening.

Sawing speed.

The sawing speed should be as close as possible to the maximum for the type of wood. If the cutting speed is insufficient or, conversely, too high, there is a chance of getting a “wave”. Saw quality. The cutting speed is directly related to the quality of the saw. Often a “wave” occurs when the saw is dull or the setting is insufficient. all of which reduces the cutting speed. The sharpening angle also affects the same. If this angle is greater than the optimal angle for this type of wood, the saw is overloaded (stuck), and if it is insufficient, the cutting speed decreases.

The uneven layout deserves a separate consideration. If the layout is different from tooth to tooth, the “wave” will have a random character, and mainly depend on the unevenness of the density of the wood. If the setting is different for different sides of the saw blade, the “wave” will depend on the prevalence of the setting (in one direction or the other) and occur when the cutting speed changes. It is possible to assume the presence of such a defect if, after entering the wood, the saw dives down or rises up.

A saw whose tooth pitch or tooth height changes from tooth to tooth will cut with jerks and significant vibration. and as a consequence, with a “wave”. If the saw has unremoved burrs, it will heat up the saw and therefore create a “wave”.

If the saw has been damaged, then, as a rule, even after straightening, it cannot provide a high-quality cut.

Wood quality.

In the occurrence of the wave, the wood is “to blame”. Basically, the matter here is in the uneven density of different layers of the log, which is due to either the type of wood, the presence of knots, or the degree of “frostbite”. It is difficult to deal with this: it is almost impossible to choose the parameters of the saw in such a way that it can cut equally well both hard outer and soft inner layers at the same time. We recommend changing the cutting pattern or leveling the surface after receiving the timber.

When sawing knotty wood, the risk of a “wave” increases. Care is needed here: you will have to smoothly reduce, and then just as smoothly increase the feed rate when passing through a knot.

If the wood is very resinous, the adhesion of sawdust and resin to the saw blade significantly increases its thickness, the saw heats up and, as a result, the tension drops and a “wave” appears. Cleaning liquid should be used.