How to sharpen a circular at home
Determination of the degree of wear
One of the conditions for correct sharpening of the tool is to determine the degree of tooth wear. The easiest and easiest way is to compare two identical saws. a new one that has not been used and an old one that needs to be edited. Simply stack the discs on top of each other and the difference becomes apparent.
Well, if the saws have already been in use, then you need to make a template in order to measure each of the saw teeth. This is a prerequisite for tool dressing. Before sharpening the disc on a circular saw, each tooth is measured independently with a template made of tin or plastic and the surface that must be processed to achieve the desired cutting edge angle is determined.
Advice! It is better to use the disks of the Ural Machine-Building Plant from Yekaterinburg as a template, these are the best saws that meet all the requirements of GOST.
Several types of circular saws are used to work with circular saws. For hand-held models, industrial-made circular saws are used, handicraft components are extremely rare. But for stationary circulars, both factory and homemade are used.
If you take a professional tool, then they are used for it:
- Carbide tipped saws. For this, the most often used is win. special refractory steel for cutting tools.
- Circular saws with hardened teeth.
- Universal saws made of tool steel.
- A tool for working with special materials. plywood, plastic, asbestos-cement boards and even stone.
Important! Sharpening of circular saws of each type has its own characteristics, which not only need to be known, but also strictly observe the technology and sequence of work.
How to know when it’s time to sharpen a disc
When working with a circular saw, regardless of its purpose, it should be understood that with prolonged use, the cutting edge will wear out. This process will take place regardless of what the saw is made of and what kind of soldering on the teeth there are.
An indicator that the cutting part will be sharpened will be the following signs:
- When working, it will take more effort to move the tool. a sharpened disk cuts material like oil, but a blunt one requires more effort to cut.
- The transverse and longitudinal cut turns out to be uneven, has torn edges. due to the fact that the saw needs to be sharpened, the teeth do not cut, but literally tear the fibers. Because of this, even a strong hand is not able to hold the tool evenly and instead of a flat mowing line, a sinusoid will be obtained.
- The saw cut of the tree will have a pronounced charred appearance. due to the fact that the teeth do not cut, but tear the fibers, the device will carbonize the cut.
- The sawdust turns out to be small, more like dust with a tinge of a rye loaf. in a sharp tool, the sawdust is larger with sharp edges.
- During operation, a characteristic smell of a fire appears. during the carbonization of the fibers, smoke appears, the disc itself heats up a lot.
- Even after short-term operation, the electric motor feels very hot, it takes more time to cool it down.
- Visually, you can determine that the teeth have lost their sharpness, and the layout has lost accuracy, individual elements have different degrees of deviation.
Carbide-tipped circular saw in various shapes
Principle and angle of sharpening of circular saw blades
Sharpening of carbide-tipped circular saws has its own subtleties and technology features. The soldering itself has four main planes — front, top and side. The corners formed by these planes represent cutting surfaces.
The main working surface is the edge between the top and front surfaces. The side edges are mainly used when the teeth are set. tilting to the right or left of the cutting axis.
Technologically, the sharpening operation is performed in two stages:
- First, the tooth itself and its surfaces are shaped.
- Then he sharpens the cutting edge.
At the same time, if the disc is severely worn out, the desired shape is first given to the tooth, its front and upper parts are leveled to the desired angle. And then both the side and the main, the edges of the victorious soldering are processed.
Carbide tooth geometry
Saw teeth, both solid made of high-speed steel, and those equipped with carbide taps have a specific shape. Some have the form of an isosceles triangle, others are crescent-shaped, and others are generally made as a trapezoid. This shape of the teeth meets several tasks.
Firstly, each mold has several surfaces forming cutting edges. Secondly, the type depends on the purpose of the tool: a fine, even tooth is suitable for cutting thin sheet materials, and a trapezoid is suitable for working with hardwood. Thirdly, the duration of use depends on the shape: the trapezoid lasts longer than the straight or sickle type.
For domestic use, discs are usually used:
- Straight teeth. for rough cutting of material. The main advantage is fast cutting of material.
- Angled and crescent teeth. designed for thin materials.
- Bevel teeth, used for finishing material cuts.
- Trapezoidal view. saws for continuous work with materials of different densities.
- Tapered teeth suitable for finishing work on materials with a smooth, glossy finish.
As you can see, it is very difficult to sharpen such discs on your own without knowledge of sharpening technologies. The most difficult thing is to maintain the “correct” angle, so that both the geometry of the cutting edge and the shape of the tooth itself are achieved on all teeth.
Improper sharpening of a circular saw blade, at best, leads to the fact that the cut will turn out to be uneven, with curved edges. And in the worst case, due to the beating that appears, the electric saw itself will have to be repaired.
Carbide brazing requiring sharpening and a new saw
Grinding methods for circulating carbide discs
To give the correct angle to the cutting edges, manual and machine methods of sharpening the tool are used.
As for the files, this should be a tool for dressing the cutting tool, and the needles with diamond.
How to sharpen a saw blade. rules
The main point in working with soldering on the teeth is the exact determination of the degree of wear. Therefore, before starting work, you need to check all the teeth without exception. The main help in this will be a metal template.
Sharpening rules can be formulated as follows:
- If the cutting edge of the tooth is rounded and the distance between the angle of the template and the edge of the edge becomes 0.1-0.2 mm, then the front or front part of the soldering is sharpened.
- If the edge is rounded more, then you need to remove not only in the front, but also in the upper part of the soldering.
- If the saw has a set of teeth, then first the tilt angle is restored, and then the face is restored.
- If the teeth have different frontal angles of inclination of the face, then first sharpening of one inclination is done, and then the inclination of the other angle is corrected.
When designing a machine for sharpening drills with your own hands, it is worth considering the types of profiles. They are set by the manufacturer and it only remains to restore after “licking”. There are 5 main forms:
- Normal view, marked with the letter “H”. The most common type, found on most edges up to 12 millimeters (not suitable for large diameters). In this case, only 2 cutting parts and 1 transverse.
- “NP” or normal with a sharpened jumper. In this case, the transverse is shorter. Suitable for edges up to 80 millimeters, as there is almost no load on the rear.
- With a sharpened lintel and ribbon or “NPL”. Essential for drilling large holes in high strength steel. Reduced cross and ribbons reduce friction.
- “DP” or double sharpened edges. In addition to the standard 2 edges, there are additional 4, representing the broken line. actively “bites” into metal, removing more metal in 1 spin.
- A similar edge, but with a groove in the tape, is called a “DPL”. Frictional force further reduces friction.
Based on nuts
A specific homemade tool for sharpening drills with your own hands, which is still suitable for beginners. Here you need a welding machine, since the monolithic body is more durable.
Sharpen Saw Blades Yourself At home! 2020
To make a sharpening tool, follow the plan:
- You will need a nut of a large diameter, for example, M 16. It is necessary to cut a triangular hole in it. You need to try to get to 120 degrees. To check this, it is enough to attach the drill with the tip.
- Another nut with a smaller diameter is welded on top. You will need it to screw in the clamping bolt.
- It remains to screw in the bolt and you’re done. The nut will be a guide and sharpening the drills with your own hands will be much easier.
Everyone can assemble such a machine for sharpening drills with their own hands, but its effectiveness is questionable. It is not worth pinning high hopes, as the nut will also gradually wear off.
In fact, these do-it-yourself drill sharpeners are disposable and will not last long. Therefore, they can be collected for training.
How the herringbone is sharpened
In fact, sharpening a step drill for metal is similar to a standard one. It has the same slope, the only difference is in the form.
How to sharpen correctly
In principle, it is possible to sharpen drills for metal without “helpers”, with proper skill.
To properly sharpen drills for metal, a tilt measure will not interfere.
To make a machine for sharpening drills with your own hands, you need to make an effort. Shop counters are expensive (from 50). At home, they are made literally from trash.
- Emphasis. The drill rests on it.
- Tightening nut with goniometer. You just need to immediately set the emphasis in the position at which inclination to sharpen drills for metal.
- Clamp for tooling. In order not to hold it with your hand and get rid of accidental cranking.
- Cutter. Allows you to move the rig.
For personal use, you can donate a carriage and angle measurer. Here is a detailed drawing of the drill sharpener.
Now it’s time to make a drill sharpener. It will suit 2 types of craftsmen:
Beginners who are unable to keep a suitable incline evenly. As a result, the edge is uneven and the drilling efficiency is reduced. Sometimes the drill starts to work even worse than before, and this reduces the speed of work. The adaptations will be useful for craftsmen who have to constantly sit at emery. In these cases, homemade drill sharpeners are a must.
Sharpening A Circular Saw Blade
From the door hinge
A homemade tool for sharpening drills with your own hands is suitable for those who know how to work with a welding machine. Next, you need to follow the instructions:
- The loop must be shortened first. One part will serve as a retainer for the handcuffs, the second (cut off part). sets the angle.
- A metal corner must be welded to the long part. A thread is cut in it to insert the bolt. Diameter is not so important, here you can act at your own discretion.
- Next, a corner is installed, it will be a guide plane.
Here is a detailed video on how to make a do-it-yourself drill sharpening machine.
It should be understood that this homemade sharpening device is not a full-fledged toolkit. A sharpener is needed, and the loop is just a guide.
Feeding is done from top to bottom. Therefore, the back of the lip will be flat and cause overheating. You will need to use coolant or at least solid oil. Not everyone will be able to orient the drill exactly, since the accuracy will be mediocre.
Sharpening principles and angles
There are four main sharpening corners at the edges of the saw. Together with the shape of the tooth, they can be the main performance 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 specific surface.
Based on the parameters indicated above, all circulars can be divided into several types:
- For slotting longitudinal holes. A 15 to 25 degree rake angle should be used for this task.
- 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.
Important! If a carbide saw has been used long enough, maximum wear will be seen at the top cutting edge. A detailed examination of the plane of the tooth shows that the anterior surface of the material suffers the most.
Types of cutting teeth
There are four planes on the surface of the teeth. front, back and two lateral.
At the moment of intersection with each other, they create a single cutting edge, due to which the sawing of surfaces occurs.
- 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 used most often 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. A 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 chances 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 dulls 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 fibreboard.
- Conical tooth. This type of tooth is considered complementary because it only helps to cut the lower part of the material (most often the 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.
Important! Each type of teeth requires a thorough grinding when sharpening. You can’t sharpen them at the same angle.
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 the formation of smoke. The circular saw has a special cover that signals when the saw has become blunt due to 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 a strong unpleasant odor are formed on the workpiece when sawing wood.
All situations described above tell the user to sharpen the device.
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.
Special saw blade sharpening machines 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. At the same time, 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 you to comfortably position the saw blade for cutting in relation to the abrasive material. Before starting work, clear markings are carried out. For this, a colored marker is used. 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.
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.
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;
- Piece of wood.
Replacing the listed devices will not work. If at least one of them is not available, then sharpening will not work.
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, they look at the abrasive wheel. To select it, certain nuances are taken into account:
Sharpening A Carbide Saw Blade By Hand
- It is best to purchase a wheel made from 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 the 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. For sharpening discs, use special machines or materials at hand. Doing the work with your own hands is not so difficult, you need to adhere to the listed recommendations and not be afraid.