Sharpening saw blades for wood is one of the most important activities for caring for a circular or circular saw. If you don't sharpen it, it will quickly become dull and become unusable.
It is most convenient to sharpen on a special production machine. However, many home craftsmen make their own design for this purpose, which significantly saves time and money.
Saws made from quality materials, they become dull less often, which means they require sharpening infrequently. However, if the discs are made of low-quality material (and this happens quite often, and even an experienced craftsman cannot always determine the quality of the metal by eye), most likely they will have to be sharpened often. Therefore any home handyman Anyone using a circular saw must know how to sharpen it.
Definition and purpose of a circular saw
A circular or circular saw is a tool whose working surface is a disk. This disc can be of different thickness and diameter, depending on the purpose. The edges of the disk are equipped with sharp teeth, which may have different shape, For example:
- Straight vertical teeth;
- Beveled teeth;
- Trapezoid-shaped teeth;
- Teeth resembling a cone.
It is used in cases where large volumes of wood need to be cut. It is convenient to work with both hard and soft wood. It can also be used to process plywood and chipboard. When the disk is rotated, the teeth cut into the material and begin to saw it. Experienced sawyers say, that working with a circular saw is much easier than with a classic one, which is a horizontal metal plate with teeth and one (two) plastic handles.
A circular saw is often used:
- At sawmills;
- On the construction of wooden houses;
- During repair work in city apartments;
- At logging.
The working surface of such a tool usually has carbide tips. These brazings are used to ensure that the teeth do not become deformed when sawing. hard rocks tree. However, sooner or later the teeth of any circular saw become dull. If this moment has arrived, then it’s time to sharpen the tool.
Disc sharpening
An experienced master usually immediately understands when the teeth begin to deteriorate. This can be determined by the following signs:
If the teeth become dull, it is advisable to sharpen the saw as quickly as possible. Many home craftsmen mistakenly believe that you can get injured from a sharp saw much faster than from a dull saw. In fact, the opposite is true. This paradox can be explained simply: when a sawyer operates a dull saw, he has to apply physical force. If you miscalculate the force or apply it in the wrong direction, it is very easy to injure your hand. And if the sawyer uses a well-sharpened tool, no effort is required, the main thing is precise and careful movements.
Using a special machine
Of course, the easiest way is to sharpen circular saw on a special machine industrial production. Such machines are quite expensive. Purchasing a sharpening machine for personal use is only beneficial if the home craftsman works daily and saws large volumes of wood . Sharpening services are also available in many specialized stores.. A saw sharpening machine is somewhat reminiscent of a pottery wheel on which a saw blade rotates, placed strictly in a horizontal plane. The sharpening process consists of the following steps:
Sharpening saw blades on a machine is very convenient. The main thing is to follow safety precautions and under no circumstances adjust the saw blade while the machine is running. All manipulations with the disk are carried out only when the sharpening machine is turned off.
Self-sharpening
Many home craftsmen do an excellent job of sharpening circular saws without a special machine. Most owners of circular saws have long been accustomed to sharpening saw blades on the fly, using an ordinary file or other available sharpening tools. However, this method is very inconvenient and traumatic. Moreover, when manual sharpening You may accidentally miss individual teeth. Therefore, this method should not be used.
Experienced sawmills usually make round saws for sharpening wooden stand, on which the saw blade is placed. The operating principle of such mini-machines is approximately the same as the operating principle of industrially produced machines.
Masters believe that before sharpening saw blades should be slightly damp - this makes sharpening much easier. To do this, sharpeners wet the saw blades with water. y and various chemicals. However, experts say that in fact this method only brings harm. Any liquid corrodes the metal and causes it to corrode, that is, contributes to the appearance of rust.
When sharpening yourself, you need to be careful not to miss a single tooth. Even if only a few teeth have become dull and the rest remain sharp, absolutely all teeth need to be sharpened. It will work correctly only if all sawing elements are sharpened equally.
Sharpening a circular saw yourself is not as difficult as it seems. How exactly to sharpen a saw, on an industrial machine or on a primitive stand, is up to each home craftsman to choose for himself. However, in any case, it is necessary to strictly observe basic safety precautions and sharpen the teeth as sharply as possible. If you encounter difficulties associated with sharpening a circular saw at home, you should consult a specialist. If you regularly maintain your circular saw, it will serve faithfully for many years.
Most cutting tools become dull during use. This largely applies to saw blades that need to be sharpened on a regular basis. This is what guarantees truly high-quality sawing wooden products. The easiest way to sharpen dull teeth is to use a standard file.
But to work with my own hands was fully fruitful, you need to seek help from a real professional. Only he can sharpen cutting tool so that it can be used efficiently.
In such a situation, it is much easier and more effective to use a home-made machine for high-quality sharpening of sharp saw surfaces, as well as a unit for processing circular knives.
Self-production of a saw sharpening machine
When in stock electrical unit for sharpening sharp surfaces, it doesn’t matter if it’s factory-made or home-made. Especially this topic is relevant when it comes to high-quality sharpening of teeth, which are made taking into account different geometric shapes and angles for turning. There are several such mechanisms and they were the result of optimization of the processing of the cutting surface, which have different properties.
The most common forms of serrated surface:
- In direct form, when concern about the quality of execution is not necessary.
- Shaped like a beveled tooth; There are two angles of the inclined surface: right and left. Typically used in circular saws. It is very often used in trimming products with lamination on both sides, because it does not show chipping cracks on either edge.
- In the shape of an oblong trapezoid. The surface is capable of holding the edge in a sharp position for a long time, rising above the teeth at a right angle. In such a situation, the teeth can be sawn black, and with straight teeth - clean.
- In the form of a conical fairing. Most often found in work on an auxiliary basis. Most often, the surface section of the laminate is cut, avoiding splinters during axial sawing.
From the front side, all the teeth consist of a flat surface, but some types of saws have a concave surface. The circular saw itself has four main angles, which form a certain shape in the intersecting plane:
- corner located on the front side;
- the angle forming the back surface;
- beveled corners in the plane of the front and rear entrance.
As an additional angle, the option with a sharpened angle is also taken into account, which forms a combination of the angles of the front and rear rows. In reality, the sharpening angle directly depends on the purpose for which the saw is intended.
- For longitudinal sawing, saws with dimensional characteristics at a rake angle of 15-20 degrees are used.
- Cross cutting for a circular saw is performed at a ratio of 5-10 degrees.
- Universal characteristics make it possible to increase the degree of inclination up to 15 degrees.
Very often, to determine the sharpening angle, an indicator such as the hardness of the wood is used. Depending on the level of hardness, the angle and size of the inclination are determined and the saw is selected accordingly.
It is by these principles that a sharpening machine for disc sawing is determined. Machines of this type have a certain design when cutting in a single way:
- During operation of the machine for sharpening circular saws, only the saw moves (the motor itself remains in its original state).
- During operation, two elements come into motion: a saw for sharpening and a motor with a circular motor parameter.
- Two standard elements also move: the saw and the motor.
A typical example is the standard homemade machine for sharpening circular saws, which can be a unit consisting of two interconnected elements:
- Grinding motor with removable shaft.
- A support pad that is attached to the disk base.
To ensure the full sharpening angle of the element, the unit always provides for a system that makes it possible to assist in changing the inclined surface on a blade with a serrated surface.
Machine tool unit JMY8-70 – benefits and distinctive features
Modern sharpening machines for circular saws, such as the JMY8-70, are one hundred percent Chinese assembled and are entirely a high-quality unit suitable for long-term use. Many specialists in self-assembly units, they take this device as an example when the need arises to make a machine with their own hands.
The main purpose of the above-mentioned machine: sharpening saws on a disk, which are based on hard alloys suitable for fast cutting of metal. The machine is capable of successfully processing the surface of the part from the front and back, as well as the ability to sharpen the corner surface at the highest quality level.
Advantages of this system:
- It is based on its own circle for processing the part using a diamond heater, minimum size radius – 65 mm.
- The saw is equipped with an inclined support, which makes it possible to sharpen the product at the required angle with a saw yourself.
- The body surface is made from special cast steel, mainly used in aircraft construction.
- The unit is installed on rubber cushioning materials. They allow you to minimize the vibration component when processing material and make it possible to drink or add water from time to time to prevent the mechanism from stopping.
- The mechanism is extremely easy and simple to adjust. Even unskilled personnel are able to operate this unit, including completely untrained specialists.
When shipping the goods, the manufacturer makes efforts to effectively control the unit. detailed instructions, which fully describes everything strengths units and methods of working with them.
Basic technical specifications related to the JMY8-70 device:
- The dimensions of the wheel for grinding have triangular parameters: 117x9x7 mm;
- The sharpened wheel can rotate at an angle of at least 20 degrees.
- The diametral surface of the saw for sharpening is at least 70-800 mm.
- The standard grinding wheel is set in motion in a matter of seconds, and its torque speed reaches 2900 rpm.
- Unit weight – 35 kg.
Many people who use manual labor, use circular saws made from complex components not on a regular basis, but depending on the need. Thus, the purchase of factory equipment may result in unnecessary financial costs. The best solution for homework is to use homemade sharpening machine for circular saws. This is why turning to third-party companies makes no sense.
As a rule, in order to turn a product on your own, it is necessary to use complex mechanisms in order to eliminate the possibility of damage to the product. For this reason, you need to use the unit that will make it possible to maintain the required sharpening angle. It is the complex machine that allows you to install the mechanism in a thoughtful position with orientation towards the sharpening wheel.
A typical unit for self-growing of a part includes:
- Electric motor with attached attachment for grinding disc.
- A stand, most often on the surface of which it is possible to locate the axis of rotation of the grinding wheel.
- The tilt of the stand is ensured by means of hinges on one side, and also thanks to a rotating moment on the other side. This makes it possible to sharpen the unit along the front and rear surfaces.
- The disk edge is fixed using special holders on which the saws are mounted. For this reason, a special groove is installed on the surface, on which the saw is fixed. Strict adherence to the rules of the instructions makes it possible to maintain the sharpening angle of the tooth surfaces.
- Material processing devices have different diameters.
- There must be high-quality stops for reliable fixation of the unit.
Video: homemade circular saw sharpening machine.
The process of sharpening circular saws with your own hands
The basic sequence for quality work includes the following points:
- Typically, the sharpened saw is placed on a mandrel and clamped with a tapered sleeve mechanism by screwing in a nut.
- By using a protractor, the product becomes clearly horizontal, while the bevel angle becomes no more than zero. Fixation occurs through the use of a pendulum protractor.
- By moving the mandrel along horizontal surface with the disk installed, set a special angle for sharpening the surface of the part; the front plane of the sharpening element is in close contact with the supporting part of the sharpening circular element.
- To correctly determine which tooth to start sharpening with, use a bright marker.
- Turning on the electric motor, a series of sawings is used, pressing the part to the surface part from the inside and outside outside to be sharpened.
- How dense the layer of metal will be removed depends only on the pressing force, as well as the number of translational movements.
- After sharpening the first tooth, the saw is removed from the circle for sharpening operations and rotated by one tooth, which also becomes the next one during sharpening.
- The operation goes through the necessary stages depending on the number of teeth that need to be sharpened.
Sharpening circular saws
Material and properties of carbide teeth
In domestic saws, sintered tungsten-cobalt alloys of grades (6, 15, etc., the pattern means the percentage of cobalt) are used as the material for cutting inserts. 6 has a hardness of 88.5 HRA, and 15 has a hardness of 86 HRA. Foreign manufacturers use their own alloys. Hard alloys consist mainly of tungsten carbide cemented with cobalt. The characteristics of an 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.
Carbide plates are attached to the disc using high-temperature soldering. The materials used for soldering are, at best, silver solders (PSr-40, PSr-45), at worst. copper-zinc solders (L-63, MNMC-68-4-2).
Carbide tooth geometry
The following types of teeth are distinguished in the form.
Straight tooth. Typically used in fast rip saws where quality is not particularly important.
Oblique (oblique) tooth with left and right angle of inclination of the rear plane. Teeth with different angles alternate with each other, due to the fact that they are called alternating. This is the most common tooth shape. Depending on the size of the grinding angles, alternating tooth saws are used to cut the most different materials(wood, chipboard, plastics). both in longitudinal and transverse directions. Saws with a high back angle are used as a trimmer when cutting plates with double-sided lamination. Their use allows you to avoid chipping along the edges of the cut. Increasing the bevel angle reduces cutting force and reduces the risk of chipping, but at the same time reduces the strength and durability of the tooth.
Teeth can be inclined not only to the rear, but also to the front plane.
Trapezoid tooth. A feature of these teeth is the relatively slow rate of dulling of the cutting edges compared to alternating teeth. They are usually used in combination with a straight tooth.
Moving with the latter and rising slightly above it, the trapezoidal tooth makes a through cut, and the straight line following it is clean. Saws with alternating straight and trapezoidal teeth are used for cutting double-sided laminated plates (chipboard, MDF, etc.) and also for sawing plastics.
Conical tooth. Saws with a conical tooth are auxiliary and are used to remove the bottom layer of the laminate, protecting it from chipping during the passage of the main saw.
In the vast majority of cases, the front side of the teeth is flat, but there are saws with a concave front surface. They are used for cross cutting finishing.
Teeth grinding angles
The grinding angles are determined using a saw. that is, for cutting the material and in what direction it is intended. Rip saws have a relatively large rake angle (15°.25°). In crosscut saws, the γ angle typically ranges from 5-10°. Universal saws designed for cross-cutting and longitudinal cutting have an average rake angle. usually 15°.
The grinding angle values are determined not only by the cutting direction, but also by the hardness of the saw material. The higher the hardness, the smaller the rake and back angles (less narrowing of the tooth).
The front angle can be not only positive, but also negative. Saws with this angle are used for cutting non-ferrous metals and plastics.
Basic principles of sharpening
Read also
When sawing massive workpieces side surfaces are also subject to rapid wear.
Do not overdrive the saw. The radius of curvature of the cutting edge should not exceed 0.1-0.2 mm. In addition to the fact that when a blade is severely dull, productivity drops sharply, it takes several times longer to grind it than to sharpen a normally dull blade. The degree of dullness can be determined by both the teeth themselves and the type of cut they leave.
Proper sharpening of circular saws must ensure, at the same time, that the cutting edge is properly sharpened to ensure maximum quantity incisors, which in the optimal case can reach 25-30 times. For this purpose, it is recommended to use a carbide tooth, which should be ground along the front and back planes. In fact, teeth can be ground along one front plane, but the amount of possible sharpening is almost half as much as when sharpening on two planes. The picture below clearly shows why this happens.
The last pass when sharpening saw blades is recommended to be done on the back plane of the tooth. The standard metal removal value is 0.05-0.15 mm.
Before sharpening, it is necessary to clean the saw from any dirt, such as resin, and check the grinding angles. On some saws they are written to disk.
Equipment and materials for sharpening saw blades
When using abrasive wheels (especially diamond wheels), it is advisable to keep them cool.
As the temperature increases, the microhardness of abrasive materials decreases. Increasing the temperature to 1000 ° C reduces the microhardness by almost 2-2.5 times compared to the microhardness at room temperature. Increasing the temperature to 1300 ° C leads to a decrease in the hardness of abrasive materials by almost 4-6 times.
How to sharpen saw blades yourself using a simple device
Sharpen carbide disks very easy with the help of a simple device, and such disks times.
Sharpening saw blades yourself
The saw blade is dull disk on my Makita 2704. Finance for purchase disk from Makita or SMT in at the moment There is not.
Using water for cooling may cause rust on machine parts and components. To eliminate corrosion, water and soap are added to the water, as well as some electrolytes (sodium carbonate, soda ash, trisodium phosphate, sodium nitrite, sodium silicate, etc.), which form protective films. For normal grinding, soap and soda solutions are most often used, as well as for fine grinding, low-concentrated emulsions.
However, when grinding saw blades at home with low intensity grinding work, the wheel does not resort to cooling very often, not wanting to waste time on it.
To increase the grinding ability of abrasive discs and reduce specific wear, you should select the largest grain size that provides the required surface finish of the pointed tooth.
To select the abrasive grain size according to the grinding stage, you can use the table in the article on grinding rods. For example, if diamond wheels are used, you can use 160/125 grit wheels for roughing or 125/100 grit wheels for finishing. 63/50 or 50/40. Wheels with grit sizes ranging from 40/28 to 14/10 are used for removing teeth.
The peripheral speed of the wheel when sharpening carbide teeth should be about 10-18 m/s. This means that when using a 125mm diameter wheel, the engine speed should be around 1500-2700 rpm. More brittle alloys are sharpened at lower speeds in this range. When sharpening carbide tools, using harsh modes results in increased stress and cracks, and sometimes grinding of the cutting edges, while increasing wheel wear.
When using grinding machines with a saw, changing the relative position of the saw and the grinding wheel can be done in different ways. by moving one saw (the motor with the circle is stationary), simultaneously moving the saw and the motor, moving only the motor with the circle (the saw blade is stationary).
Produced large number grinding machines of various functions. The most complex and expensive programmable complexes are capable of providing a fully automatic grinding mode, in which all operations are performed without the participation of a worker.
In the simplest and cheapest models, after installing and fixing the saw in a position that provides the required sharpening angle, all further operations rotate the saw around its axis (rotating the tooth), submitting it for grinding (bringing it into contact with the wheel) and controlling the thickness of the saw metal. are made by hand. Such simple models It is advisable to use at home when sharpening circular saws is occasional.
An example of the simplest machine for grinding discs y saws is the system, a photograph of which is shown in the photograph below. It consists of two main blocks. motor with a circle (1) and a support (2) on which a pointed saw is mounted. The rotating mechanism (3) serves to change the angle of the blade (when sharpening teeth). Using the screw (4), the saw moves along the axis of the abrasive wheel. This ensures that the specified front grinding angle value is set. The screw (5) is used to set the stopper in the desired position, preventing the wheel from excessively entering the interdental cavity.
Saw blade sharpening process
Read also
The saw is mounted on a mandrel clamped using a conical (centering) sleeve and nut, and then installed in a strictly horizontal position using a mechanism (3). This ensures that the front plane inclination angle (ε 1) is 0°. In disc grinding machines that do not have a built-in angular scale in the tilt mechanism, this is done using a conventional pendulum goniometer. In this case, check that the machine is level.
The rotation of the screw (4) of the mechanism, which ensures horizontal movement of the mandrel with the wheel, sets the required cutting angle. In other words, the saw moves to a position where the front plane of the tooth fits snugly against work surface circle.
The marker marks the tooth from which sharpening begins.
The motor is turned on and the front plane is sharpened by inserting the tooth into contact with the wheel and making several back and forth motions while pressing the tooth against the wheel. The thickness of the metal removed is regulated by the number of sharpening movements and the force of pressing the tooth on the abrasive wheel. After sharpening one tooth, the saw is removed from contact with the wheel, it turns on one tooth and the sharpening operation is repeated. And so on until the marker pen makes a full circle, showing that all the teeth are pointed.
The tooth sharpening is inclined on the front plane. The difference between sharpening a beveled tooth and sharpening a straight tooth is that the saw cannot be mounted horizontally, but at an angle corresponding to the angle of the rake plane.
The angle of the saw blade is set using the same pendulum goniometer. First the positive angle is set (in this case 8°).
After this, every second tooth is sharpened.
After sharpening half of the teeth, the saw blade angle changes from 8° to .8°.
And every second tooth is sharpened again.
Back sharpening. To sharpen a tooth on the back plane, it is necessary that grinding machine saw blade made it possible to install the saw in such a way that the rear plane of the tooth was in the same plane as the wheel.
Circular saws are used throughout construction. Many works require changing the dimensions of the used building materials, creating cuts and much more. A circular saw allows you to quickly cut the most various materials, while the cutting speed is very high, and the quality of the cut made is the best. The constant use of the equipment in question determines that the cutting tool begins to become dull, which has a significant impact on the efficiency of the work performed and its quality. This is why many people think about how to sharpen circular saws with their own hands. After all, the ability to perform such work efficiently will allow you to save significantly.
Required Tools
You can sharpen disks for a circular plate with your own hands only if you have special tools. There is also a machine that allows you to automate the process and make it more efficient.
To carry out the work of sharpening a disc with your own hands, you can use the following tools:
- assembly vice;
- file;
- block of wood.
You can also use a circular saw sharpener, which does not require the above tools.
When is it necessary to carry out restoration work on circular saws?
Enough important issue can be called a determination of when circular saw blades should be sharpened. Excessive wear may make it impossible to carry out such work. Three clear signals can be identified that determine the need to sharpen the disc. circular saw:
- Smoke appears, the protective casing heats up. The device usually has a special protective cover, which can become hot if the blade becomes dull. It should also be noted that in special cases, smoke appears due to the strong heating of the cutting zone.
- Also, with mechanical feeding, when the pressure is adjusted with your own hands, great force should be applied to obtain the desired result.
- When processing wood or other material, traces of soot and a corresponding odor appear in the cutting area.
Principles and angles of sharpening circular saws
The saw has four main sharpening angles for the circular saw blade along the working part. The angles under consideration, like the shape of the tooth itself, can be called basic performance characteristics. Each tooth can be characterized as follows:
- front and back angle;
- cutting angles of the front and back surfaces.
The values of the above parameters depend on the purpose of the sawing device and the type of workpiece material.
Based on the above parameters, several saws can be distinguished:
- for performing longitudinal cutting. In this case, the rake angle should be from 15° to 25°.
- when performing cross cutting, the considered indicator should be from 5° to 10°.
- The universal version is recommended to be sharpened at an angle of 15°.
The type of material being processed also determines what characteristics the tooth should have. As a rule, the harder the material, the more difficult it is to machine. That is why it is recommended to sharpen the cutting teeth to a lesser extent.
With prolonged use of a carbide saw, significant wear occurs on the uppermost cutting edge. When considering the tooth plane, it is worth noting that most wear occurs on the front surface.
Sharpening circular saws at home
You can sharpen the saw yourself without using a special tool. grinding machine, which has a high cost and is rarely used for its intended purpose due to the use of carbide material when creating the cutting edge. However, you cannot simply hold the circle in your hands, since you need to achieve certain cutting parameters to ensure the required performance indicator.
To fix the gear wheel in a strictly specified position, an ordinary flat stand is used. It has the following features:
- The surface of the flat stand should coincide with the level of the axis of the sharpening disc.
- We place the toothed wheel on the stand so that the sharpening plane is perpendicular to the saw blade.
- The device in question for teeth located at a certain angle is equipped with a rotary hinge.
The device in question makes it possible to fix the element being processed in relation to the abrasive material used. Using a colored marker, marking lines are drawn that allow you to select correct angle. A vice is also needed in which the created fixing device is attached.
Sharpening using a machine
If it is possible to purchase a special machine, then the process in question can be carried out with maximum efficiency. Similar device It has a compact size and can be used at home.
Particular attention is paid to the choice of abrasive wheel. In this case, we note the following nuances:
- Carbide blades are difficult to sharpen.
- When choosing, you should pay attention to wheels made of CBN, with diamond chips or green silicon carbide.
- How to sharpen
- Important to know
- Assembling a homemade sharpener
From time to time you need to sharpen the cutting element of the circular saw. Sharpening circular saw requires certain knowledge special equipment. There are machines designed for these purposes.
Types
Machines for sharpening circular saws are a group of devices for restoring the sharpness of cutting elements. Depending on the functional features, they are:
- Automatic. The units are installed at large enterprises.
- Semi-automatic, mechanical (tools for sharpening cutters manually). They are characterized by low productivity and are mainly used in home workshops.
When sharpening chains for rip sawing Other devices are used that can sharpen each tooth using files.
All equipment included in the package electric drive, similar in principle of operation. Only the performance differs. Thus, low-power household samples can operate continuously for up to 20 minutes. Afterwards they must be turned off for the same time to cool.
Professional tools can work up to 8 hours. They only need a few short breaks of 20-30 minutes. Some units have an abrasive wheel for sharpening and a sanding belt with a similar effect.
In most cases sawing tool can be sharpened on machines, the main element of which is a sharpening disc. Belt devices are more suitable for industrial use with large volumes of fine sanding.
Grinding machines are equipped with wheels that differ in:
- thickness - 16–40 mm;
- outer diameter - 12–250 mm;
- mounting hole - 12,7,16, 20, 32 mm;
- material of manufacture.
You need to pay attention to what the abrasive is made of. special attention: the result of the work depends on the quality. In addition to conventional cutters, there are wheels that have reinforcing soldering - a plate made of hard alloys. The most common are corundum and diamond wheels. They do a good job of sharpening carbide-tipped blades designed for cutting particularly hard materials.
The installation circle must be purchased taking into account the characteristics of circular saws. The abrasive belt is selected according to the size of the machines. The grain size, which affects the nature of the grinding, is also taken into account.
How to sharpen
The abrasive disc is cleaned of dirt, residues removed material, set the angle of inclination. Sharpening begins from the front of the tooth. The maximum metal layer allowed for removal is up to 0.20 mm.
It is necessary to ensure correct feeding of the cutting element to the sharpening disc. The wheel to be sharpened must be in contact with the abrasive with its entire surface. During the work, you need to ensure that the blade does not overheat. You can avoid increasing the temperature of the material to critical levels by adjusting the rotation speed of the abrasive element and wetting it with a small amount of water before work.
Circles with diamond coating Those processing pobedite cutting tools are usually cooled with a special liquid (coolant). The process can be considered complete after the appearance of a uniform burr over the entire surface of the blade edge. Final sanding is done by hand.
It must be remembered that the machine can only process a workpiece in one plane at a time.
Important to know
The main wear of the saw occurs on the upper edge of the teeth. It comes into most contact with the material being processed. Due to constant contact with hard surfaces, the rounding of its central edge can reach 0.3 mm. This is a critical indicator. It is necessary to ensure that the central protrusion is rounded by no more than 0.2 mm, otherwise it will be difficult to sharpen the element well and will take a lot of time.
The degree of wear is usually determined by the condition of the teeth and the quality of the cut. Each cutting disc has a resource. In most cases this is 30-35 sharpenings.
Do not allow the formation of nicks, chips, or other defects on the cutting edge during its processing using machines that violate the integrity of the metal.
Assembling a homemade sharpener
They resort to making a homemade sharpening machine in the case when there is no factory equipment at hand, and the cutting wheels periodically have to be sharpened. The device can be used to sharpen a dull circular saw blade.
For assembly you will need:
- electric drive,
- caliper,
- tilt mechanism,
- screw stops.
The circle must be fixed to the engine. The disk blade is installed on the support, while the screw stops ensure the movement of the cutter along the axis of the circle, creating the required angle of inclination. Correct fixation of the saw blade relative to the abrasive is the main requirement for sharpening. To ensure that the angles are maintained, you will need an adjustable stand mounted in the same plane as the circle on the frame of the device. When installing the disk on the stand, you need to ensure that the teeth are placed perpendicular to the plane of the machine.
When assembling a device for sharpening circular saws yourself, it is recommended to use drawings and diagrams.
Sharpening can also be done mechanical devices. But when using special units, the operating time is reduced; a sharpened cutter will have a sharper edge.