What is the best saw for cutting planks?. Electrodynamic brake

What to saw with

What can be done with the board? For sawing, for example. You measure it all out about seven times, mark it out, let’s saw. Let’s saw, of course, with a saw, but what kind of saw?? Saws, as you know, come in handheld, electric and gasoline-powered.

Let’s see what kind of saws there are first. In stores and markets there is enough of this stuff, and domestic specimens are not inferior to similar imported. Finally, we have learned how to make sturdy blades and more or less comfortable handles that do not rub on your hands when working. By the way the price of “our” and imported saws is not very much different. In one of the next issues I will tell you about hand saws in details, but now I want to give you some useful tips about what you should know when buying a hand saw.

Firstly you should never buy Chinese-made hacksaws or interchangeable blades (especially on metal). They saw badly, but break well. probably because of violation of hardening technology. It is a waste of money.

Secondly, so-called “self-sharpening” saws are now on sale. As the salespeople explain, the saw “sharpening itself while working due to the friction against the material to be treated”. That’s why, they say, such a saw always stays sharp. Do not believe it. miracles do not happen. It is the same as your car while driving will not only consume fuel but also produce it by itself. “The secret” of these “miracle saws” is ridiculously simple: the blade is made of a harder material than usual, so it remains sharp for several times longer. But beware: when the saw does blunt, it will be very difficult for you to sharpen it again. precisely because of the hardness of the material! (By the way, to sharpen an ordinary hacksaw with a file and file is not difficult. technologically. To describe this process on paper is a thankless task. In any village you can find a craftsman who will be happy to explain it to you “on his fingers”.)

Let’s go further. Next on the list. the electric saw. There are a lot of models from different manufacturers, which, of course, differ in price and quality. It is clear that the principle of operation is the main difference between the available types of electric saws, but practically all of them (to a certain extent) are interchangeable.

Let’s classify them. Electric saws, like everything in this world, there are imported and domestic. The imported ones are divided into circular saws, jigsaws, mitre saws (the principle of operation is the same as for circular saws), sabre saws, chain saws and electric joinery saws. Domestic electric saws are divided into circular, jigsaw, and chain saws. Other kinds, at least I am not aware of.

Let’s start with the electric circular saws. Their cutting tool is a metal disk with sharp teeth, which rotates at high speed around its own axis. The circular saw is used to make long, straight cuts. The saw can be held in the hand and move relative to the surface to be cut, and you can fix the saw in the base and move the material to be treated (for large amounts of work it is best to do so).

Circular electric saws are very useful for country house construction and repair work. Here is, for example, a specific case.

I know a guy who had golden hands. He was earning pretty good money. he “worked hard” from dawn till dusk. And I spent my long-awaited vacation in stuffy Moscow. Sometimes, of course, he would go to a resort, but A man had no heart for such a vacation. So he decided to build himself a house in the suburbs. I bought a plot, put a log house, and began to attach a terrace. And then. a painfully familiar story to all: the crisis, loss of work, casual and insignificant earnings In general, the frame for the terrace is made, but there is nothing to upholster. no “gold” stock.

And then a miracle happened! A man had the opportunity to “privatize” edging boards in sufficient quantities to upholster the terrace. Well, of course, he privatized this “humpback”, and then what? To upholster the terrace with “humpback boards”? It’s not pretty. Such a structure will be more like a barn, and you need, as you know, a terrace. That’s where the “circular saw”, bought in better times, came in handy (what model. I do not know). In short, the man sawed a normal edged board from this wood. not “super”, of course, but quite “level. Upholstered a terrace, and still on the barn left. And at free time my acquaintance made a calculation. It turned out that in the end he fully recouped the cost of his saw. This summer the man is quite successfully “hacking” with his “circular saw”, i.e. he gets a net profit. That’s the story.

But just in case: the circular saw quickly pays for itself if you are engaged in building seriously and for a long time. For “piece-work” jobs, it is worth buying a low-end, cheaper, used saw.

Now about different kinds of circular saw blades. There are discs with and without hardfacing: For “piece-work” jobs it is a good idea to buy a low-cost home-grade saw, maybe a second-hand one. Blade-less discs are generally used for clean and beautiful cuts in soft wood. The disk will not cope with hard wood, let alone metal. If you accidentally hit a nail in the sawn board, the disk will have no teeth. There is no way to reanimate it: there are no “inserts” for this purpose.

In this sense models with tungsten carbide tips seem much more interesting. Such circular saw blade will easily saw a nail “in the tooth” and safely continue its (your) work. But here we have to put up with the fact that working with such a disk, the cut is not very clean, even a little “shaggy”.

About tooth shape: they can be, I dare say, active (positive angle) and passive (negative angle). Let me explain: if a tooth is bent as if in the direction of the disk rotation, this is a positive angle of sharpening; if against. negative. The positive angle allows to cut wood, wood with nails, plastic, etc.п. Negative angle will be able to saw, for example, tinplate and copper. Theoretically, such a disk can also saw wood, but the cut is very “chunky”: the teeth do not cut, and tear into the wood fiber. So before you choose a disk, you should decide what kind of work you need it for? And the salespeople will tell you the exact model.

Now for the specific models. I am pleased to note that circular saws are produced that are not inferior to their imported counterparts either in design or reliability. 1200 watt power, 200 mm blade, up to 65 mm cutting depth, equipped with blade guard. Price at the beginning of summer was about 1300 Manufacturer. Moscow Radio Technical Plant. A similar model is produced in Perm, the price is the same.

The main characteristics that are worth paying attention to in the first place

The most common models on the market have a motor power of 0.8 to 2.2 kW and speed 4.5-5.5 thousand per minute, weight ranges from 3 to 7 kg. When choosing, these 3 parameters are the most important, you should pay attention to them in the first place.

Power

The higher the power, the better. But it should be remembered that the more power, the higher the cost, weight and power consumption. That’s why users most often choose medium-powered models, from 1.0 to 1.6 kW. An exception is when the tool is bought for not quite standard, “average” tasks. for sawing thin or thick material only. In the first case, the most low-power variant is enough, in the second vice versa.

Tip To make a cut of the depth declared by the manufacturer (for example, 5,5 cm) the power of the installed engine should be enough by definition. But the more powerful variant will cut faster, with less effort and less load, which increases productivity and increases tool life.

Platter RPM

The higher the speed of the blade, the more accurate and clean the cut. But according to the laws of physics, “more speed, less force”. Therefore, for the same motor power, a “faster” disc spins with less force.

The range for the most popular models and manufacturers is small, from 4.5 to 5.5 thousand rpm, so there is not much difference in performance. Nevertheless, experienced specialists notice a difference in disk rotation speed.

Tip For fine, clean carpentry work, a higher rotational speed is preferable. For construction work, a low, higher force is better.

cutting depth

It is directly related to the distance at which the saw blade comes out of the bed (support platform) at a right angle at most. When slanting sawing, the depth is reduced. For example, a tool with a cutting depth of 54 mm can saw a bar with a section of 100 mm if you make the cut on both sides of the bar.

Changing the angle

Almost all circular saws of this type are equipped with this function (from 90 to 45 degrees). When selecting the sawblades, pay attention to the quality of the assembly. The screw clamps must be strong enough and preferably made of metal (the plastic handles of clamps on low-end models often break off). The corner arc itself must be made of metal strong enough not to bend.

Circular saw blade

In practice each manufacturer makes saws for the disks of its own size. To pick up a suitable disc from a saw of the same power of another brand is not always possible. There are coincidences, but not always.

The difference in seating and outside diameters of only a few mm leads to the fact that “someone else’s” disc is not suitable.

Tip When choosing discs, avoid intricate, shaped, or complexly shaped teeth. Such blades cannot be sharpened, or can be sharpened using expensive and rare special equipment.

In the end, instead of sharpening and further use, you have to throw them away and buy new ones. Whereas standard shank can be resharpened, increasing the service life several times over.

There is a lot of information on the circular saw blade and the numbers indicate the most important ones. 1. Manufacturer. 2. Model and type of disc. 3. Dimensions. 4. Type of tool used. 5. Type of material to be sawn. 6. Disc size. 7. Number of teeth. 8. Seating diameter. 9. Max speed. 10. Direction of rotation.

Top hacksaw models

There are many factors to consider when choosing a hand-held wood saw. First, the purpose for which the tool is to be used. Secondly, the components of the hacksaw: saw blade, size and shape of the teeth, handle (it must be comfortable). The saw has to be user-friendly and sharp. Below is a list of the best hand held tools for wood, according to the parameters and opinions of buyers.

STANLEY JET CUT SP 2-15-288

Carpentry saw, blade size. 50 cm, the teeth are suitable for longitudinal and transverse cutting. Gross weight 0.5 kg.

Zubr “EXPERT”

Devices on wood from the company Zubr are represented by the following models:

• EXPERT 15071-45: cross-cutting saw, blade length. 45 cm, teeth pitch. 3,5, weight. 0,34 kg.
• EXPERT 15071-40: crosscut saw, length. 40 cm, pitch. 3,5, weight. 0,33 kg.
• EXPERT 15073-45: crosscut saw, length. 54 cm, pitch. 5, weight. 0,34 kg.

STANLEY OPP 1-20-089

Carpentry tool, blade length. 38 cm, hardened teeth. Gross weight. 0,5 kg.

BAHCO 396-LAP

Length of blade. 19 cm, foldable, corrosion-resistant, locks in closed and open position. Gross weight 0.215 kg.

Enkor Wolfman 9858

For cross-cutting wood, blade size. 40 cm, tooth pitch. 4 mm, ground at three angles, which is a big plus for speed. Gross weight. 0,35 kg.

Enkor Beaver 9857

Metal blade made of high-strength steel, for longitudinal and cross cuts, length. 50 cm, the teeth are sharpened at two angles, so they are quite universal. Gross weight 0.5 kg.

IZHSTAL 030108-050

For joinery works, blade size. 50 cm, pitch. 6,5 mm, designed for two types of cuts. Gross weight. 0.46 kg.

Varieties of electric and gasoline-powered saws

Gasoline and electric tools have a motor or motor that allows the tool to rotate. Less effort on the part of the operator and higher working speed. Some versions of the tool are self-contained and suitable for field conditions, others are mains-powered and need a 220V outlet. Here are the main features of this category of saw.

The chainsaw is a chain saw

The chainsaw is powered by a combustion engine. Needs gasoline and lubrication for the small cutting part. Tool varies in bar length, which comes in 35 to 60 inches. This affects the ability to cut a specific trunk diameter in a single-sided approach.

Arrangement

The cutting element is the chain, which consists of links and teeth projecting outward. It is looped and runs on an oval bar with a guide rail. The operator holds the machine by the main and auxiliary handles. Sawing can be done horizontally or vertically.

Changing and tightening the chain is done by the tensioner on the side. If the cutting tip jams in the material, the saw will rebound. Increases safety with chain brake that activates if plastic safety stop collides with operator’s hand.

Purpose

The exhaust fumes are enough to use this type of tool only outdoors. Gasoline-powered saws are often used for felling wood and cutting firewood. Their self-contained gasoline engine makes them suitable for continuous use in the field.

But the tool is quite versatile, so it is used almost everywhere:

• Building log houses and bath houses;
• Cutting firewood in the backyard
• Sawing down garden trees;
• carving concrete or ice sculptures.

Thanks to the powerful engine, the chainsaw can handle tough materials extremely well and withstand serious workloads with dignity. But it is an expensive tool that requires proper maintenance.

Electric chainsaws

They are similar to gasoline-powered ones in the type of cutting part and use the same chains. But thanks to the electric, rather than gasoline-powered, have both advantages and disadvantages. Within their own species, they are categorized by bar length and power.

Device

The electric motor is located in front of the main handle and is mounted longitudinally or transversely. In the first case, the electric saw is obtained with a narrower body, and in the second. with a shorter. This is worth considering when choosing for use in tight spaces. All chain saws of the network type are connected to 220 V. There are cordless versions for 36 V.

Electric saws are lighter than chainsaws, making them less hand fatiguing and ideal for long days of use. They do not produce exhaust fumes and can be used both indoors and outdoors. Their design is even simpler (only the electric motor, gearbox and accessories), so they cost less and can be repaired inexpensively.

But the presence of a power cord limits the maneuverability of the operator, and sometimes it just gets in the way (when working at height or frequent bypassing around a large workpiece). Cordless electric saws are not as powerful and are limited in how long you can use them by battery capacity.

Purpose

Generally, it is a universal tool, but the cord allows its use only in the vicinity of a power outlet. Saw wood in the yard, build wooden houses, cut openings for doors and windows in wooden houses.

Sabre saw

Named for its curved, saber-like cutting element. Also called electric sabre saw by craftsmen.

Device

It has an electric motor and reduction gear that makes the saw blade go back and forth. These repetitive reciprocating motions with high frequency are used to cut. A stop on a second handle near the tool is provided to protect the operator’s hands. The main handle comes in L-shape or D-shape. Some models have a step speed switch, which helps set the desired speed for a particular material.

Tool is cordless or cordless. Pros and cons for the type of power supply are the same as for the other saws: the mains-powered version limits mobility and requires a socket nearby, while the battery-powered version is autonomous for one hour only. Requires a second battery for extended use without interruption. Then the batteries can be alternated by changing in the tool and charging in the base.

Purpose

The compactness and low weight are the main features of the sabre saw. That’s why it’s used at heights or in hard-to-reach places, where it’s not convenient to operate a chain saw or a hand-held circular saw.

For example, it is well suited for roofing work. Model can cut not only wood. Special interchangeable blades let you cut stone, concrete, metal. There are saw blades that can be used to make neat cuts in combined materials.

Alligator saw

A variation of the sabre saw, but designed for bigger objects and larger workpieces. Named for its two serrated blades that resemble the double serrated alligator blade. The tool can be cordless or cordless. The first kind is much more expensive.

Device

Has handles on the engine block and a long guide rail. Two blades move along the underside of the bar in opposite directions. Stroke length can be up to 40mm. This ensures a smooth cut and minimizes lateral drift of the cutting line. When the blade dulls, it is replaced with a new one.

Purpose

The alligator saw is most often used for cutting aerated concrete and building blocks similar in structure and density. It is lightweight and suitable for cutting bricks perpendicularly or diagonally. But two blades in the composition increases the thickness of the cut, which is important to consider when calculating the dimensions of materials.

Circular (circular) hand saw

Holds with one hand and can be used for lower and upright cuts. The circular saw is called a circular saw because of the disc’s rotation as the main cutting element. Due to this design it is very compact. There are 220 V and 36 V cordless versions.

Device

Consists of a D-shaped single handle, transverse motor to whose shaft a steel disk with teeth is attached. The high-speed rotation of the working part ensures a fast cut through the wood. Circular saw blade is protected by a running cover that automatically closes the teeth after taking the saw away from the board. Depending on the diameter of the disc, the cutting depth can be up to 50-60 mm.

Basic settings

The efficiency of a wood secateurs depends largely on its technical characteristics. The main ones are:

When choosing a tool, it is necessary to pay attention to each element of the characteristics. Only in this case you won’t regret the purchase.

Blade material

Modern wood hacksaw blades are made of high quality tool (alloyed) steel with increased carbon and silicon (65G, 8KhF, U7U10). Hardness should be not less than HRC 45. There are also models where combined, more wear resistant blade with cutting part (teeth) having higher hardness (HRC55 60) is used.

Length and shape of the blade

On the domestic market it is possible to meet wood saw blades of length from 250 to 650 mm with the step, multiple of 25 mm. This parameter is specified by GOST 2615-84 and depends on the distance between the teeth.

Please note! It is necessary to choose the saw following the rule: “the length of the blade must be twice the thickness (diameter) of the piece of wood”.

Otherwise it will be uncomfortable to work with the hacksaw, because the short blade will jam inside the solid wood.

Hacksaws with narrow blades are commonly up to 350 mm long and have a greater number of fine teeth. Universal tools are completed with blades of about 500 mm length with medium-sized teeth. Saws with wide blades are made with large teeth spaced far apart (coarse pitch), their length can reach 650 mm.

Traditionally, wooden saw has a shape of a triangle narrowed on one side. It can be used on all types of wood. There are also sabre saws adapted for sawing e.g. on tree branches or other objects at a distance from the user. They have a rounded shape and are lightweight.

Tooth size and shape

The tooth pitch of a hacksaw blade directly affects the performance and accuracy of the tool. The coarser the teeth, the faster the cutting speed, but the precision and quality of the cut suffers. Using a saw with coarser teeth gives a cleaner, straighter cut but lowers the speed.

Cut accuracy is determined by the number of teeth per inch of blade length (TPI), that is, their density. Its value is marked on the side of the blade (for example, 7×1″ or 7TPI). The higher the TPI, the less the pitch. So 2TPI = 12mm and 12TPI = 2mm.

Choosing a hacksaw for wood, it is necessary to take into account that the minimum thickness of the workpiece should be greater than the pitch of the three teeth.

The type of the sharpened teeth is of great importance when working with a wood hacksaw. Teeth that are sharpened on both sides and have a sharp or isosceles triangular form are considered standard.

Important! Latest generation saws are available with irregularly shaped carbide-tipped teeth. They have a trapezoid shape and are distinguished by three sharpened edges and increased wear resistance. Blades with these teeth cannot be re-sharpened.

Type of handle

The type of handle and the material of which it is made largely determine the ease of working with a wood hacksaw. It is best to work with a saw that has a solid plastic handle with rubberized inserts for your fingers. The two-piece handle is less comfortable because it is not rigid enough.

Hacksaws with flip-over handles are also common. As a rule they are equipped with them for universal and onion saws that have the possibility of changing blades in the process of work.

The main parameters to pay attention to when choosing

These are characteristics, failure to comply with which the disc just does not fit the tool.

Outer diameter

Discs with a large variation in diameter can be used in stationary circular saws, especially in handmade circular saws. Small for cutting thin workpieces, large for large-sized wood. It is desirable to have a set of different drives.

It is not convenient and comfortable to saw thin wood with a big blade diameter. unnecessary loads on the motor because of a big blade lever, too thick kerf, big overhang of the blade over the workpiece, what reduces the safety of sawing.

The maximum diameter on stationary circular saws is limited by the size of the blade slot or cover, if available.

Minimal. sufficient protrusion over the desktop.

Handheld circular saws have no such variation in diameter. they use the same diameter disc that was installed at the factory. In exceptional cases the disk smaller by 3-5 mm can be suitable, but it will change the important characteristic. depth of cut. A blade too big just does not fit or touches the guard.

Fitting diameter

In Soviet times, there were only two fitting diameters for stationary circular saws and trimmers. 32 mm and 56 mm. Nowadays producers all over the world produce 18 mm, 20 mm, 30 mm etc. drive shafts and discs in various sizes.д.

Nevertheless, the standards remain, although there are more of them. And it is understandable. no backlashes are allowed here. The disc must fit tightly on the shaft, otherwise you won’t be able to work with it. A bore that is too small will make it impossible to fit the disc on the shaft, while one that is too large causes misalignment, wobble and vibrations incompatible with operation.

Sometimes for compatibility of different diameters adapter rings or washers are used. For example, by using a washer with an inside diameter of 32 mm and an outside diameter of 56 mm, it is possible to mount a disc with a seating diameter of 56 mm on a seating shaft with a diameter of 32 mm.

The 1 mm thick trim ring allows a 32 mm disc to be used on a 30 mm shaft, and so on.д.

Thickness

The parameter does matter. Thin blades have a number of advantages and disadvantages over thicker blades. Advantages:

The latter, especially important when sawing high-value wood. sometimes only 2-3 mm determine, for example, how many bars will come out of the board. 5-6 with a thin disc, or 4-5 with a thick disc.

Thin saw blade makes a 2 to 3 mm cut. Thick. 3-4 mm. Sometimes a large blade with a wide serration can make a 5 to 6 mm cut.

• are prone to bending, so sometimes the kerf can be wavy,
• Can overheat quickly, sometimes to the point of “turning blue”, which can put a blade out of order completely. Overheated blades start to wag in various degrees of amplitude, sometimes up to 10 mm or more.

Thicker and thicker discs are slower but more stable.

Variety

Two fundamentally different types of discs are used:

The first is of the outgoing type. Widely used at a time when there was no technology for precision and durable carbide soldering. Nonetheless, monolithic blades still have a number of advantages:

• very long tool life, limited only by the fact that in time, after many sharpening operations, the disc diameter reduces to a critical size,
• easy sharpening and dressing of teeth,
• possibility of changing the shape and angles of sharpening,
• No soldering, one-piece tooth strength.

Disadvantages. the teeth need regular dressing, sharpening and resharpening, because their strength is inferior to hard-alloy teeth.

They are not cheap, because not only teeth, but the whole mass is made of special tool steel.

To carry and hold carbide cutting teeth without wiggling and overheating, other, cheaper steels are suitable. They are used today on discs with soldered tines.

The quality of such a blade greatly depends on the composition of the carbide. Most manufacturers keep their formulations secret. However it is well-known that the most durable were old Soviet discs with “pobeditovye” teeth.

Tungsten carbide, cobalt and other elements are used in alloys today. Simple domestic discs are not very durable: they break off, the solder bounce off, and quickly wear down to zero after several sharpenings because of their small size. But the professional expensive discs from brands with a good reputation can serve for a long time and require sharpening less often.

Number of teeth

The number of teeth determines the cleanliness of the cut. it is important that it is not only the number of teeth, e.g. per 10 cm of circumference, that makes the difference, but most importantly their size. If there are many teeth, they are small in size. Smaller teeth saw more slowly and cleanly, less material tearing out.

The difference in the work of a disc with a small number of large and a large number of small teeth is very significant.

• Coarse-serrated blade uses less friction, makes it easier on the motor.
• The blade gets less heat.
• Large and rare sawdust is formed.
• Drive slices faster.
• At the output, the large tooth can tear out pieces of material, especially on plywood, chipboard, etc.д.
• Residual circular bands and tooth marks may be left on the saw.

A disc with fewer teeth and more of them produces fine sawdust.

• Heats up more because of friction, the wood may burn.
• Requires motor power reserve, as disc can be braked out of friction.
• Finer tooth at higher RPMs tears material less at the exit.
• Bands-free, clean, brushed appearance at high RPM.

Blades with sparse, coarse teeth are better for a simple, quick cut. For a better cut, diagonal or cross-cutting a tooth with many fine teeth is best.

Tooth Geometry

Two tooth shapes are used on all modern discs:

The shape of the first variant is well tested, calibrated and calculated. The forward-facing cutting tip of the tooth ejects sawdust. The void beneath the carbide tooth does not create friction, makes it easier for the disc to move, and reduces heat. These blades are successfully used for longitudinal, diagonal and cross cutting.

Jigsaws

An electric jigsaw consists of a motor, a pendulum mechanism that reciprocates the tool (file) and a support plate. Machine base can be rotated in different directions and fixed in the chosen position, which makes it possible to make cuts in the workpiece at different angles.

The jigsaw is designed to perform longitudinal, curved and cross cutting of different types of sheet materials (plywood, laminated chipboard, plastic, fiberboard, metal, etc.).д.). The main characteristics to which you should pay attention when choosing a unit, are listed below.

• Sawing frequency. Different models of devices can have a frequency of reciprocating movements in the range from 500 to 3000 strokes per minute. This characteristic affects not only the cutting speed, but also the durability of the equipment. Higher frequency may be set in soft materials (wood, plastic), but a lower frequency is required for metal and composite materials.
• Depth of cut. Household jigsaws are able to cut 60-100 mm thick sheets of wood and 4-6 mm thick steel. But for cutting steel and other hard materials, it is better to use professional tools, because during this operation there are quite large loads on the pendulum mechanism of the device. As you know all parts of a pro class tool are made of stronger, higher quality materials.

All electric jigsaws have a function to control the frequency of movement of the file with the start button. The harder the trigger is pulled, the higher the frequency of vibration of the cutting tool.

Cutting tools and the mechanics of how they work

If you leave stationary sawing machines out of the equation, there are not many alternatives to handheld operation. Of the available tools you can offer circular and pendulum saws, in common parlance are called sortsovki and jigsaws. It is also possible to make a fairly high-quality cut with an angle grinder, on which a wood saw blade with teeth made of pobedite is mounted. But this is not the most efficient, nor is it a very safe solution.

During cutting with any type of electric tool, working bodies move at very high speed, and therefore the mechanics of machining remain as if behind the scenes. But understanding it is the key to a clean, chip-free edge. The simplest principle is at the heart of reciprocating saws. The cut is made with a straight saw blade motion, and the size of the removed fragments depends entirely on the size of the tooth and its camber.

Chips occur due to the heterogeneity of the material to be machined, in particular due to the hard crust of laminated sheet materials or because the fibers in solid wood have different densities. Chipping can occur on different sides of the workpiece depending on the shape of the tooth, the feed force and the speed of the jigsaw. When using a jigsaw, chipping is caused either by the teeth tearing out large chunks from the backside or by the overcutting of the top layer, which breaks out in large chunks instead of cutting them off.

The teeth of the circular blade work much like a jigsaw, except that their motion is directed strictly in one direction and they move at a very high speed. Also important is the direction (angle) of the applied force: if the jigsaw moves strictly perpendicular to the surface, the circular saw cuts at an arbitrary angle, depending both on the blade diameter and on the thickness of the workpiece. This can play into the hands: the oblique plunge of the tooth contributes to a more accurate cutting of chips, but on the reverse side due to the movement of the cutting edges tangentially can tear out quite large fragments. Of course, the circular saw can only make a straight cut.

How to cut a quarter in a board with a circular saw?

For this the desired cutting depth is set. For choice of a quarter in the size 20×20 disk should leave the platform at 20-22 mm (the addition to the uneven surface of the board). For cutting a sharply-sided quarter, for example, 15×20, the depth adjustment is set twice for each size, at 15-16 mm and 20-22 mm.

Later the operation is performed in the same way as sawing edged board: at the required distance is set the guide bar on two rods, sawing is done on a wide plane. Then the board is placed on the edge and a second kerf is made.

Because the edge is narrow, difficulties may arise. on some models, the guide bar may not pull up close to the platform. In this case, a bar is attached to the board (or bar) with screw clamps or self-tapping screws, which increases the width to the desired dimensions.

If it is not possible to make an edge cut with a guide bar, it can be made by pencil marking. It is difficult to hold a circular saw on the edge of a narrow board (20-30 mm). In such cases, it is sometimes more convenient to either screw a support bar or place the workpiece between two bars (boards) on which the saw platform will move.