Sharpen Circular Saw With Soldered

Using a special machine

• The grinder takes out a marker, which writes on metal, and marks with a marker the tooth required to start sharpening.
• The disc is placed on the machine;
• The grinder turns on the machine and drives the mechanism;
• The tool is sharpened in a circle. First, the first tooth is processed, then the third, fifth, and so on. Every second tooth is processed;
• When one sharpening circle is completed, a new circle begins. This time every second tooth is processed that was not processed the first time;
• This cycle is repeated several times, depending on the number of teeth on the saw blade. If the disc has a small diameter, two or three cycles are sufficient for sharpening. If it is a large disc with a lot of teeth, it can take quite a while to fully sharpen. And also the time spent on sharpening depends on the power and speed of the grinding machine.

It is very convenient to sharpen saw blades on the machine. The main thing is to observe safety precautions and in no case adjust the saw blade while the machine is running. All manipulations with the disc are performed only with the grinder turned off.

Alternative solutions

Alternative sharpening methods include the two methods we described above. They are quite effective, therefore they are often used by masters.

• Full profile saw blade processing. Among all turning methods, this method can be considered the most accurate and high quality. This is due to the fact that specialized grinding machines are used for full-profile sharpening. A special wheel is selected by size and in one approach passes the entire cavity between the teeth of the disc, while capturing the surface of the adjacent cutting edge. This technique of turning saw blades avoids the possibility of deformation of the tooth circle. The only drawback of the sharpening method is that to process saws of different profiles, you will need to use the corresponding different circles.
• Cutting edges of teeth. The popularity of this method of turning circular saw tools is due to the fact that it can be used on a professional level and in ordinary household conditions. If sharpening is done with a machine, you will need to purchase the appropriate abrasive wheels to match your saw blades. But it is optimal for most circular saw owners to use the home processing method. This is due to the fact that often it is not required to carry out a large amount of work, and the entire processing of the cutting edges is carried out with a file. To effectively sharpen the product, sometimes it is enough to carry out 4-5 movements with a high-quality file. This will give the teeth the necessary degree of sharpness.

Classic

This sharpening technique has been used for a long time, which is why it got its name.

• Sharpening starts from the back of the disc.
• The front part, which runs into the material during cutting, remains in its unchanged position.
• Processing can be carried out directly on the circular saw or the saw blade can be removed by placing it in a vice.
• If you are sharpening on a circular, be sure to disconnect the machine from the power.
• To secure the disc, use a pair of blocks to secure the circle like wedges. The bars must be firmly pressed against the workpiece to prevent movement when turning.
• Use a felt-tip pen to mark the first tooth you will start with.
• Perform a certain number of movements with the grinder on the first tooth. Remember their number.
• For all subsequent teeth, repeat the same amount and intensity of movement.
• Upon completion of sharpening, be sure to check the performance of the do-it-yourself saw. If there is no abnormal noise, vibration and the disk machine behaves stably, you managed to do the job correctly.

Saw Blade Sharpening Tools

To properly sharpen a circular saw, you need tools such as:

• File;
• Mounting vise;
• Wood block;
• Color marker.

Sharpening discs

An experienced craftsman usually knows right away when the prongs start to deteriorate. This can be determined by the following criteria:

• Visual deformation of the teeth (individual teeth may bend or break off);
• During sawing, the master has to make great physical efforts in order for it to work efficiently;
• Some seasoned sawers check the sharpness of the teeth by touch. However, this method is not recommended, since any careless touching of the teeth can result in a finger injury;
• Often makes an unpleasant creak or crackle during operation. During the sawing process, you can clearly hear the wood squeak.

If the teeth are dull, it is advisable to sharpen the saw as quickly as possible. Many DIYers mistakenly believe that injury from a sharp saw can be much faster than from a blunt one. In fact, the situation is exactly the opposite. This paradox can be easily explained: when a sawer uses a blunt saw, he has to apply physical force. If the force is incorrectly calculated or applied in the wrong direction, it is very easy to injure the hand. And if the sawer uses a well-sharpened tool, no effort is required, the main thing is precise and accurate movements.

Types of cutting teeth

To better understand how the correct sharpening of circular saws is performed, you should understand the features and structure of the part of the blade that cuts wood. This main part is the cutting teeth.

All teeth are made from carbide metals. Each of them (Fig. 1) has 4 working flat surfaces: front (a), back (b), as well as two side planes (c). They play a supporting role. One main (1) and two additional (2 and 3) cutting edges are formed on the lines intersecting the specified work planes.

According to the configuration, all cutting teeth of circular saws are divided into the following types:

Figure 2. Grinding angle diagram.

• Straight teeth. Most often used for accelerated ripping. Not designed for perfect cut quality.
• Beveled (oblique) teeth. They are characterized by the presence of an angular cut on the left or right side on the back flat surface of the tooth. Sometimes on the disc, teeth with different sides of the bevel alternate and then they are called alternately cut. Such elements are used for cutting not only wood, but also chipboard, various plastics. A large bevel angle ensures high-quality sawing without chips at the cutting edges.
• Trapezoidal teeth. In the section of the cutting surface, they have the form of a trapezoid. Thanks to this configuration, they do not dull for a long time. Often the disc alternates with straight teeth. In this case, the trapezoidal elements perform rough sawing, while the straight ones perform finishing.
• Tapered teeth. They have a conical appearance. Usually they perform auxiliary functions of preliminary cutting of the laminate. These teeth are used to process the specified floor covering to prevent chipping when cutting laminate panels with the main saw.

How to sharpen a soldered circular disc

The construction of a private house will be difficult and time-consuming without the use of modern tools. The circular saw has gained great popularity among builders, surpassing other types of saws for wood with its precision and cleanliness of sawing.

Diagram of a machine for sharpening circular saws and knives.

Since this power tool belongs to the actively used and therefore quickly worn out device, sharpening circular saws with your own hands becomes very important.

General rules for sharpening

Photo of ways to sharpen circular saws

As in the case of chainsaw sharpening, self-sharpening requires adherence to certain recommendations.

• Pay close attention to uniform metal removal along the profile of the saw blade teeth;
• Never press the saw blade firmly against the grinding wheel. If the machine for sharpening circular saws is in close contact with the sharpened wheel, this will lead to overheating and further deformation of the material;
• Keep track of the preservation of the height and profile of sharpening upon completion of processing operations;
• When sharpening discs, use coolant. This is also recommended for those who carry out turning chainsaw chains;
• Avoid burrs when turning the saw blade;
• When sharpening the edges, rely on an important rule. It is necessary to sharpen only the front, or the front and back of the tooth. Although in practice, many craftsmen with their own hands prefer to sharpen from the back of the saw wheels, considering this method more convenient;
• Products with victorious solders are sharpened with diamond sharpening devices. Only such tools are able to truly effectively restore the cutting properties of a given tool. You can use a regular file, but in fact it will not give the desired effect.

What signs will tell you to sharpen the saw?

Figure 1. Diagram of a saw tooth. Planes: a. front, b. back, c. two lateral. Edges for metal cutting: 1. main, 2, 3. additional.

You should only sharpen your circular saw when the need arises. And the fact that such a moment has come will be signaled by 2 clear signs. In particular, urgent sharpening of circular saws for wood is required if:

• Strong heating is felt on the saw guards in the vicinity of the electric motor. Sometimes such an increase in temperature is accompanied by the appearance of smoke from under the casing.
• To obtain good results, the saw blade must be pressed harder than before.
• As a result of the work of blunt teeth of saws on wood, the appearance of dark marks and traces of carbon deposits is recorded in the cuts in the wood. The characteristic smell of burnt wood may spread.

If there is no saw blade sharpener

Accurately maintaining the required sharpening angles while holding the saw in your hands is an overwhelming task even for a person with a unique eye gauge and enviable firmness of hands. The most reasonable thing in this case is to make the simplest sharpening device, which makes it possible to fix the saw in a certain position in relation to the circle.

The simplest of such devices for sharpening circular saws is a stand, the surface of which is flush with the axis of the grinding wheel. By placing the saw blade on it, you can ensure that the front and back planes of the tooth are perpendicular to the saw blade. And if the upper surface of the stand is made movable. fixing one side with a hinge, and the other. leaning on a pair of bolts that can be turned in and out. then it can be installed at any inclination, getting the opportunity to sharpen an oblique tooth along the front and back planes.

True, in this case, one of the main problems remains unresolved. maintaining the same front and rear sharpening angles. You can solve this problem by fixing the center of the saw relative to the abrasive wheel in the desired position. One way to do this is to make a groove on the surface of the stand for the arbor on which the saw is mounted. Moving the mandrel with a circle along the groove, it will be possible to maintain the required rake angle of the tooth sharpening. But for sharpening circular saws with different diameters or sharpening angles, it must be possible to either move the motor or the stand and the groove with it. Another way to provide the required sharpening angle is simpler, and consists in installing the stops on the table to fix the disc in the desired position. At the end of the article there is a demonstration of such a device.

Classic

This sharpening technique has been used for a long time, which is why it got its name.

• Sharpening starts from the back of the disc.
• The front part, which runs into the material during cutting, remains in its unchanged position.
• Processing can be carried out directly on the circular saw or the saw blade can be removed by placing it in a vice.
• If you are sharpening on a circular, be sure to disconnect the machine from the power.
• To secure the disc, use a pair of blocks to secure the circle like wedges. The bars must be firmly pressed against the workpiece to prevent movement when turning.
• Use a felt-tip pen to mark the first tooth you will start with.
• Perform a certain number of movements with the grinder on the first tooth. Remember their number.
• For all subsequent teeth, repeat the same amount and intensity of movement.
• Upon completion of sharpening, be sure to check the performance of the do-it-yourself saw. If there is no abnormal noise, vibration and the disk machine behaves stably, you managed to do the job correctly.

Material and properties of carbide teeth

In domestic saws, sintered tungsten-cobalt alloys of grades VK (VK6, VK15, etc.) are used as material for cutting inserts. The number means the percentage of cobalt). BK6 has a hardness of 88.5 HRA, BK15 has 86 HRA. Foreign manufacturers use their own alloys. Hard alloys VK consist mainly of cobalt-cemented tungsten carbide. The characteristics of the alloy depend not only on its chemical composition, but also on the grain size of the carbide phase. The smaller the grain, the higher the hardness and strength of the alloy.

Attach the carbide plates to the disc by high-temperature brazing. As a material for soldering, at best, silver solders are used (PSr-40, PSr-45), in the worst case, copper-zinc solders (L-63, MNMTs-68-4-2).

When to sharpen a circular saw

There are very definite signs by which one can judge the state of the instrument. Sharpening saws is necessary when the following is clearly manifested:

• During operation, smoke appears, a specific smell of burnt wood, the casing covering the saw teeth begins to heat up quickly.
• When moving the tool along the workpiece, you need to apply significant efforts, as if to push the saw forward.
• After cutting the material and visual inspection of the sawn edge, black carbon deposits or a lot of chips, fiber scuffing, chipped areas are visible.
• A close examination of the saw teeth with a magnifying glass shows that the cutting parts are not sharp, but rounded edges.

All this requires an immediate cessation of work, otherwise there is a great risk of damage to the material and wear of the circular saw to such a state when sharpening will no longer help it.

Alternative solutions

Alternative sharpening methods include the two methods we described above. They are quite effective, therefore they are often used by masters.

• Full profile saw blade processing. Among all turning methods, this method can be considered the most accurate and high quality. This is due to the fact that specialized grinding machines are used for full-profile sharpening. A special wheel is selected by size and in one approach passes the entire cavity between the teeth of the disc, while capturing the surface of the adjacent cutting edge. This technique of turning saw blades avoids the possibility of deformation of the tooth circle. The only drawback of the sharpening method is that to process saws of different profiles, you will need to use the corresponding different circles.
• Cutting edges of teeth. The popularity of this method of turning circular saw tools is due to the fact that it can be used on a professional level and in ordinary household conditions. If sharpening is done with a machine, you will need to purchase the appropriate abrasive wheels to match your saw blades. But it is optimal for most circular saw owners to use the home processing method. This is due to the fact that often it is not required to carry out a large amount of work, and the entire processing of the cutting edges is carried out with a file. To effectively sharpen the product, sometimes it is enough to carry out 4-5 movements with a high-quality file. This will give the teeth the necessary degree of sharpness.

The main sharpening angles of circular saws

The circular saw tooth, which is usually made of carbide metal, has a complex structure. It has three cutting edges as standard, so you need to sharpen the teeth so as to sharpen these edges. But the main thing when sharpening is to observe the angles at which the planes of the tooth diverge from the edges, and the angles of attack between the plane of the tooth and the workpiece. The last point is important to maintain the performance of the saw blade.

The front face, the one that first cuts into the workpiece in the direction of the saw movement, forms the main cutting edge with the rear face. The angle at which the leading edge meets the material is called the Y-angle (angle of attack). The angle between the back face and the front face is the taper angle. If you subtract the rake angle and the taper angle from 90 degrees, you get the clearance angle.

In practice, it is important to observe these angles when sharpening for each type of disc. It is according to the front angle that the saws are divided into types:

• Longitudinally cutting where the rake angle should not go beyond 15-25 degrees.
• Transverse cutting, where it is permissible to sharpen the front face of the tooth at an angle of 5-10 degrees.
• Universal discs, which are easy enough to cope with both longitudinal and transverse cuts, their rake angle should be maintained in the region of 15 degrees.

The angle of the bevel of the rear and front planes is also important: the sharper it is, the easier it is for the saw to enter the material, but wear occurs faster.

Signs of wear

Sharpening saws is a common activity, as is turning chainsaw chains done by hand. You can entrust the tungsten carbide fixture to the specialists. This is due to the fact that the victorious solders have increased hardness, which makes it impossible to sharpen with an ordinary file. This will require an expensive diamond grinding tool.

The first thing you need to do is determine the current state of the saw blades. Chains and discs have certain signs of wear. If you know about them, you can easily find out that the sharpness of the circular saw has deteriorated significantly.

• Temperature has started to rise significantly on the engine cover of your saw blade.
• To cut the workpiece, you have to apply more physical effort with your own hands. A similar phenomenon is typical for dull chainsaw chains.
• Smoke may occasionally come out of the engine.
• An unpleasant burning aroma is generated when processing workpieces.
• Darkening occurs at the edges of the saw wheel. This is carbon deposits. It can also appear on the surface of chainsaw chains.
• The wooden workpiece begins to move around the machine in jerks, although with normal sharpening, the movements should be smooth.
• There is extraneous noise during machine operation.
• The geometry of the teeth of the saw wheels of your circular saw is broken.

How can you sharpen a circular saw

Sharpening discs is impossible without the use of a special tool. For these purposes, you can use:

• Special wheels for sharpening saws, made on the basis of diamond abrasives.
• A regular file for sharpening a saw, but you also need to have a vise to secure the saw and a block of wood to use as a guide.
• Processing on professional equipment is the fastest and highest quality way of sharpening, but it requires large material costs for purchasing a tool.

Manual way

It is possible to independently sharpen the teeth by hand using a file, so that it is of high quality, if they do not have a bevel, that is, the surface of the front face is perpendicular to the surface of the blade. The process looks like this:

• A block is prepared from dense wood with a cross section of somewhere 50×50 mm and a length of 100 mm. The sides of the bar should be located strictly perpendicular to each other.
• Mark with a marker any tooth that will be reportable and the first to be processed.
• The saw blade is clamped in a vice together with a bar so that the front edge of the workpiece is flush and in the same plane with the surface of the bar (the bar in this case acts as a file guide).
• A thin file (its thickness should allow it to fit freely into the cavity between adjacent teeth) is applied to the surface of the tooth to be treated and at the same time sharpening is carried out to the bar and methodical movements back and forth.
• So each tooth is gradually sharpened, monitoring the state of the bar and, when working out its surface, slightly shifting the plane.

How to sharpen a circular saw blade correctly and at what angle

The use of circular saws is especially common in construction. Most of the work requires cuts and changes in the shape and size of the finished materials. The circular saw helps you tackle these tasks quickly and get quality results. But the instrument is not capable of serving forever, sooner or later it may become dull. It is for this that you need to know exactly how you can sharpen saw teeth in a domestic environment.

Types of cutting teeth

There are four planes on the surface of the teeth. front, back and two side.

At the moment of intersection with each other, they create a single cutting edge, due to which the sawing of surfaces occurs.

There are several forms of teeth:

• Straight tooth. Most often it is used only for a quick longitudinal cut. During such work, quality and accuracy are practically unimportant.
• Oblique tooth. The back plane of such a part is tilted to the right or left. On saws, these teeth often alternate, which is why they are called “alternately cut”. These teeth are most commonly used in tools. The size of the corners can be different, this is due to the coating of the treated surface. wood, chipboard, plastic. They are used for longitudinal and transverse movements. The large angle of inclination on the tools is used when cutting boards with double-sided lamination. This helps to avoid chipping of the material. The larger the chamfered corner, the easier the saw will cut through the surface. But this greatly increases the likelihood of tooth breakage. On some products, the teeth are inclined not only at the back, but also at the front.
• Trapezoidal tooth. The main advantage of this type is that the edge blunts slowly. But they are rarely used separately, usually alternated with straight teeth. During the operation of the device, the trapezoidal teeth are located above the straight ones, therefore they take over the main (rough) sawing work. Straight teeth for finishing. This saw design is used for sawing plastic, chipboard and MDF.
• Conical tooth. This type of tooth is considered optional because it only helps to cut the lower part of the material (most often laminate). This design allows you to protect the surface from chips and cracks. Bevel teeth usually have a straight front edge, but it can also be concave. This type is used for finishing the saw cut.

Sharpening principles and angles

There are four main sharpening corners on the saw edges. Together with the shape of the tooth, they can be the main operational characteristics of the tool. The following are used to describe each tooth:

• Front and back angle.
• Cut angles of the front and back surfaces.

These characteristics may depend on the type and weight of the circular saw, its purpose, as well as the density of the particular surface.

Sharpening angles in the diagram

Based on the parameters indicated above, all circulars can be divided into several types:

• For slotting longitudinal holes. When performing this task, use a rake angle of 15 to 25 degrees.
• For cross-cutting. In this situation, the rake angle can vary from 5 to 10 degrees.
• Universal sharpening. Saws are sharpened at an angle of 15 degrees for any operation.

The size of the sharpened angle is not only determined by the direction of movement of the saw, it is also related to the material of the workpiece. When cutting through very hard materials, the smallest angle should be chosen. To work with softer products, the angle increases.

How to determine wear?

Checking the saw blade for wear is an important issue that should be given special attention. Deep damage leads to the inability to sharpen the circle. There are three main signs by which you can understand that the saw needs to be sharpened or replaced:

• Excessive heating of the protective cover and formation of smoke. The circular saw has a special cover that signals when the saw is blunt by heating. In especially difficult situations, smoke may appear from it.
• Sometimes the saw device involves a mechanical feed (if you need to adjust the pressure with your own hands). In such a situation, wear can be noticed if the pressure has to be increased.
• If carbon deposits and strong unpleasant odors form on the workpiece when sawing wood.

All situations described above tell the user that the device should be sharpened.

How to sharpen: basic methods

There are two methods available for sharpening circular saws. manual and machine. In order to sharpen the disc correctly at home, you need to take into account some of the nuances.

Tools

It is allowed to sharpen the saw with your own hands only when using special devices. For this, there is a grinding machine that helps to carry out the process on an automatic machine, and not manually. Then the result becomes more accurate.

In addition, other improvised devices are used for sharpening:

• Mounting vise;
• File;
• Piece of wood.

It will not work to replace the listed devices. If at least one of them is not available, then sharpening will not work.

Manual way

Special machines for sharpening saw edges are rarely used in a domestic environment, because their cost is high. Therefore, in the absence of such a device, you can cope with sharpening with improvised devices, for example, an angle grinder. In this case, it is forbidden to hold the circle in your hands without fixing it with anything. Otherwise, it will not be possible to achieve a sufficient cutting angle for further work with the material.

To securely fix the circle in the correct position, use a flat stand.

• The surface of the stand coincides with the level of the axis of the grinding wheel;
• On it, the gear wheel is placed in such a way that the sharpening plane becomes perpendicular to the saw blade;
• The design of the device is complemented by a swivel joint.

The stand will help to comfortably position the saw blade for processing against the abrasive material. Before starting work, clear markings are carried out. A colored marker is used for this. They draw a mowing line, which will allow the element to be sharpened at the desired angle. The vise will help secure the disc to the surface.

Sharpening disc for circular saw angle grinder:

Using a machine

When the foreman has access to a special grinding machine, the elements are processed quickly and efficiently. This device is small in size, so it is comfortable for a beginner to work with it. There will be no problems even when used in a domestic environment.

When buying such a device, look at the abrasive wheel. To select it, certain nuances are taken into account:

• It is best to purchase a wheel made of diamond-coated CBN or green silicon carbide;
• If the carbide wheel is sharpened, problems may arise even when using the machine.

The very process of using a sharpening machine is extremely simple. The operator should comfortably position the disc on the device and clamp it using a special retainer. Before starting work, it is recommended to mark the first tooth with a marker. This will help not to get tangled during sharpening, and not to check teeth that have already been processed. To select the sharpening angle, a special meter is provided on the device. The required angle should be set on it, after which the device will complete the task on its own.

The circular saw is a useful tool that you cannot do without during construction. It helps to make cuts in surfaces, as well as change their shape and size. To sharpen discs, use special machines or materials at hand. It is not so difficult to do the work with your own hands, you need to adhere to the listed recommendations and not be afraid.