How to choose a miter saw - detailed instructions + Video

How to choose a miter saw for an ordinary consumer, if he has such a need? The most logical solution is to seek help from a consultant in a specialized store: he will explain everything, tell and even show. However, in order to make the conversation with a specialist more substantive, it would be nice to get at least a general idea of ​​the tool before going to the store.

The purpose of the miter saw

The name "miter" itself indicates the purpose of this saw - the design of the ends of the workpiece, cutting wood across the fibers. In this, it differs from its closest relative - a circular saw, which is used, as a rule, for longitudinal cutting of wood.

Modern powerful engines and extremely durable saw blades allow trimming to cut not only wood, but also plastic, thin metal profiles and pipes, and wood-based composite materials. For these materials, the concepts of "longitudinal" and "transverse" are very conditional: if such terms are used, then we are not talking about the structure of the material, but about the shape of a particular blank. Of course, the shape of the workpiece can be very diverse, sometimes without a clearly defined longitudinal axis.

The applicability of a miter saw in one case or another is determined solely by the convenience of feeding a particular workpiece. Thus, the name “miter saw” cannot be considered as fully reflecting the potential of this tool, just such a name has historically been fixed to stationary circular saws with a movable cutting unit.

The miter saw can cut material not only at a right angle, but also at an arbitrarily chosen angle, for which it is sometimes called electric shock. Moreover, in many modern devices it is allowed to change the angle not only in the horizontal, but also in the vertical plane, i.e., it is capable of sawing under an inclination. With the miter saw, you can even select grooves if necessary.

As you can see, the possibilities of this tool are much wider than you might have thought at first. It is not surprising that trimming can be more and more often found on small joinery plants, on construction sites, in home workshops. Their help is resorted to in the manufacture of window frames and doorframes, in laying floors (cutting parquet, laminate, baseboards) and other finishing works (sawing carpentry, various aluminum and plastic profiles), in the manufacture of wooden furniture.

The device and functionality of the miter saw

The trimmer is easy to understand from the figure, which shows the main components of the tool. Everything else is just add-ons that do not change the principle of operation, but only improve functionality and usability.

The main elements of a miter saw are an electric motor and a saw blade made of high-quality heavy-duty steel. The engine, the saw blade and the gearbox connecting them constitute a functional unit, and here is a handle with a toggle switch.

The entire unit is attached to the base — the bed on which the sawn billet is being laid. On the basis of the fixed turning circle, moving when setting the angle of the cut, and emphasis. The beds of relatively expensive devices are made from durable and light aluminum or magnesium alloys, which ensures not only the reliability of the base, but also the mobility of the entire instrument by reducing weight.

The function block is connected to the frame via a pivot arm using a spring-loaded hinge. The swivel arm is called the pendulum, and the miter saws of this type are called the pendulum.

The pendulum provides movement of the working module. To perform the cut, the lever must be lowered down, "drowning" the saw blade in the stationary workpiece (for unimpeded sawing there is a slot in the turntable of the bed). This is the simplest version of the miter saw. As a rule, all modern models are equipped with a mechanism that ensures the rotation of the desktop along with all the mechanisms in the horizontal plane.

Thus, the guides and table elements remain stationary, and the tool itself changes position in the horizontal plane. The use of such a tool provides more opportunities for trimming.

For combined type saws, there is another hinge that allows the lever to rotate relative to the vertical axis (i.e., for such saws, the cutting angle can be changed in two planes). Often, turning around the horizontal axis is allowed only in one direction - opposite to the electric drive.

But there are models that allow tilting in both directions.

Such technical solutions repeatedly expand the list of the tool's functionality. Sloping in relation to the vertical cutting allows you to face the workpiece height which is greater than the active radius of the disk.

The cutting width of the miter saw is relatively small, especially when working at an angle or tilt. For example, an average pendulum saw with a 10-inch disk at right angles will cut a bar 95 * 95 mm or a board 69 * 135 mm (if you install any other angles, the allowable size of the workpiece decreases). In other words, the miter saw is not suitable not only for longitudinal cutting, but also for cross-cutting wide workpieces.

To increase the width of the cut, the saw is equipped with a traction function. The working unit at the trimming with such a function moves not only around the axis of the hinge, but also along the cutting line along the guide rods, thanks to which the maximum cutting width at an angle of 90 ° increases from 80–180 mm to 280–340 mm. Such tools are called crosscut saws or horizontal saws.

In this case, the mechanisms for moving the saw along the workpiece differ depending on the manufacturer and model of the device.

Species and choice of engine for trimming

Most often, the engine of the miter saw is located to the right of the work disk. However, for some units, it is shifted back to maximize the view of the working surface (regardless of what hand the operator works with) and not to create obstacles with an inclined cut - for such saws, as a rule, there is an inclination of the working head in both directions.

Two types of electric motor are installed on the trimmers - asynchronous and collector.

Asynchronous motor

An asynchronous motor is considered more economical, reliable, and silent. It has no contacts whatsoever, which means there is nothing to make noise, overheat and break down under the influence of external factors - dust, humidity, vibration. In addition to bearings, there is simply nothing to wear there, so such units can serve without any complaints for decades. However, not all manufacturers of power tools seek to equip their products with such seemingly ideal engines, since they have asynchronous motors and their own drawback - low power with sufficiently large weight.

For example, a 2-kilowatt engine of this type weighs more than 20 kilograms. You must admit that it is quite difficult to manually move the work unit with such an appendage. In addition, when powered by industrial frequency, an asynchronous motor, in principle, is not able to reach speeds above 2850 rpm. / min Of course, the use of modern materials and the supply of high-frequency current to the engine to a certain extent level these problems, but they do not completely remove them.

The collector engine

The collector engines look much more attractive in terms of size and power. With a comparable mass, the torque of the collector motor is several times greater than that of the asynchronous one. He is able to issue up to 5-10 thousand vol. / min and the organization of the system of control and stabilization of revolutions is much simpler.

It is not surprising that despite the disadvantages of collector engines (high noise level, the need for regular maintenance to replace the collector brushes) most miter saws are equipped with them.

Brushless Motor

However, there is one more option based on modern semiconductor technologies - the golden mean between asynchronous and collector types of the engine. We are talking about valve or brushless motors (marked with the letters BL from English brushless - brushless). In valve engines, the brush-collector assembly has been replaced by an electronic unit characterized by negligible resistance and an enormous switching speed of electronic power valves.

This type of engine combines all the advantages of asynchronous and collector - high torque and efficiency, quiet operation, unpretentiousness external factors, long service life, no need for regular maintenance.On modern high-quality miter saws, it is increasingly often valve motors that are installed, because their only drawback - the high price - is more than offset by such a large number of advantages.

Types of gearboxes, their advantages and disadvantages

The connecting link between the electric motor and the saw disk is the gearbox that transmits and converts the motor torque. On miter saws use two types of gearboxes - with gear or belt drive.

Gears that provide a stiff bunch of shafts seem more reliable. They do not slip and do not fly off like a belt, and there is nothing to tear there. It would seem that manufacturers miter saws should give preference to such a reliable system. However, in practice, the belt drive on these tools can be seen more often than a gear. What is the reason? Reliable gearing has a downside. In the event of an emergency situation, the gear reducer can fail, and then it will require its complete replacement or serious repair in a specialized service center.

The “unreliability” of the belt drive can also be viewed with different eyes. Yes, sometimes the belt flies or even breaks, but to install it in place or replace it with a new one does not require special knowledge and skills - an ordinary user will cope with this task. In addition, the belt provides some cushioning of radial and axial vibrations, which helps reduce wear on bearings and other engine components. When an emergency tool overload (for example, when the saw blade is jammed), even a well-tensioned belt will slip, which will save the metal parts of the motor from destruction. And the noise of a saw with a belt drive produces incomparably less, which is also a rather significant factor.

Miter Saw with Belt Drive.

By the way, some manufacturers (including such authoritative ones like Bosch and DeWalt) have excluded the gear unit from a number of their models, having installed the saw disk directly on the motor shaft. This solution also has its pros and cons. On the one hand, the load on the bearings increases, on the other hand, the noise emitted by the tool is reduced, the design reliability increases, and maintenance and repair are simplified.

Power and number of turns

The power of the miter saws can vary from 800 to 2500 W depending on the model. 1600-1800 W is considered the golden mean - tools of just such power are most in demand today, because they cope with their task equally well in home workshops and in small production.

What gives us the knowledge of the value of such a parameter as power consumption? First, the correct correlation of the power of the miter saw and the structure of the material being processed will avoid overloading the tool, which prolongs the time of its active operation.

Secondly, the greater the power of the saw, the greater the diameter of the disk that can be mounted on it. As an example confirming this statement, let's compare two trimming saws from Bosch. On the model PCM 7, whose power is 1100 W, you should select a disk with a diameter of not more than 190 mm. But for the GCM 10 J Professional with a capacity of 2000 W, a disk with a diameter of 254 mm is suitable. It should be borne in mind that with an increase in the power of the saw and the outer diameter of its disk, the dimensions and weight of the tool increase. So, the first of the models given as an example weighs 9 kg, and the second is already 14. 5 kg.

Another technical characteristic that you should pay attention to when choosing a miter saw is the number of revolutions of the saw blade. The value of this parameter lies in the range from 3200 to 6000 rpm. / min A clean and high-quality cut (without chipping the coating, splitting off wood fibers, etc.) is possible only when working at high speeds. So, for example, when the saw blade diameter is 260 mm, its angular speed must be at least 2800 rpm. / min In expensive professional models, the angular velocity, as a rule, is not lower than 4000-5000 vol. / min even with large disc diameters. A number of manufacturers offer miter saws, the number of revolutions of which can be adjusted depending on the type of work being done at the moment.

Additional devices

Practically in all modern models of miter saws there are various additional devices and functions aimed at facilitating work and increasing safety. The future user of the tool will have to decide at the stage of selection which of them are really necessary to solve the typical tasks facing him, and which will be an unjustified waste of money.

1. A dust removal system consists of a nozzle and a dust collector bag or industrial vacuum cleaner hose connected to it.The second option is preferable because it allows you to more effectively trap the fine dust of the material being processed, which is formed when performing an accurate cut, when the saw is running at high speeds and / or discs with an increased number of teeth. The dust removal system should not be considered as an additional, optional function, even if you are faced with the task of choosing a miter saw for the house, that is, a low-intensity episodic work on it is assumed. Working without a dust removal system, you risk not only the safety of the equipment available in the workshop (and first of all the saw itself), but also your own health.

2. The protective casing completely covers the working disk until it plunges into the material being cut, which significantly reduces the risk of accidents when working with a miter saw.

3. The cutting depth limiter is used to carry out work on slotting or profile trimming.

4. The laser "draws" a guide line on the workpiece at the point where the saw makes a cut. The presence of this option improves the accuracy of cutting (especially when sawing at angles other than 90 degrees), facilitates the work, reduces the time for pre-preparation.

5. Illumination of the working area can be useful when working in workshops or workshops with insufficient general lighting.

6. A smooth start provides a gradual set of engine speeds when turned on, thereby preventing tool “jerk” at start-up, reducing the risk of saw failure due to a sharp current jump and the likelihood of tool jamming at the start of work.

7. Automatic shutdown when the saw blade is jammed is another useful feature aimed at improving safety when working with a miter saw.

8. Adjusting the number of turns allows you to vary the cutting speed. Most models miter saws this feature is missing. However, it allows a better adjustment of the sawing process for the particular material being processed. It is recommended for those who intend to work not only with wood, but with various materials based on it, plastic, plexiglas, etc.

9. Support constant speed during load increase. In the presence of such a function, engine revolutions do not drop with strong pressure, since the electronics make their corrections to speed. As a result, the cut turns neat and clean.

Saw blades

Often, beginning masters, who do not have sufficient knowledge, but who have a great desire to acquire a new tool, ask the question: "How to choose a miter saw on wood?" This question is not entirely correct. Any trimming will cope with the wood cut, because for this purpose it was created. But how much you enjoy the result of the work depends not so much on the tool itself, but on the tooling installed on it — the saw blade.

Outer and bore diameter of the disc

The main parameters when choosing saw blades, which should be paid attention to first of all, are the dimensions of the outer and bore diameters. Most of the miter saws produced today are designed to work with discs whose bore diameter is 30 mm.

There are exceptions with a deviation both in the one and in the other direction, but there are relatively few of them. The outer diameter of the saw blade varies much wider. Most running - wheels standard 10 inches and 12 inches. It should be borne in mind that under 12 inches can mean both 300 mm and 305 mm, and under 10 inches both 250, and 255, and even 260 mm, and even the same manufacturer can have discrepancies. Smaller (185-216 mm) and larger (up to 360 mm) diameter discs are less common, since the corresponding equipment is less available.

Increasing the diameter of the saw blade allows you to process workpieces of a larger section, while increasing tool productivity and cutting quality at the same speed. However, larger drives require higher torque, and therefore additional power reserve. However, using saw blades whose outer diameter exceeds that specified in the tool passport will not succeed: the trimming design simply will not allow installing such a snap-in that will save particularly careless users from dangerous experiments. It is possible to install a smaller disc, but this is not recommended.This will lead not only to the loss of the effective radius and productivity of the tool, but also to a decrease in the calculated dynamic resistance, with the result that the engine can “go into a spacing” in the absence of stabilization of revolutions.

Technical characteristics of saw blades

Matching the size of the footprint and a suitable outer diameter of the disk is a necessary but not sufficient condition for using it to perform a particular operation on the miter saw - there are plenty of other nuances that also must be considered.

In addition to the outer and inner diameter, the discs may differ in the following characteristics:

• material type;
• thickness;
• number and size of teeth;
• tooth form and angle of inclination;
• allowable rotation frequency.

Material type . By the type of material from which the discs are made, they are all divided into monolithic and carbide. Monolithic manufactured from high carbon or high-speed steel. They quickly dull, but are subject to sharpening, and you can do it yourself. Carbide discs made of durable tool steel have hard-alloy solder tips on the tips of the teeth (in most cases it is tungsten carbide). Such discs, despite the high price, have earned popularity among specialists due to their reliability and long service life.

Monolithic and carbide disc.

The thickness of the disk is . The thickness of the saw blade determines the cutting width and mode of operation. Thin discs are more often used for cutting valuable types of wood, they are economical in material consumption, but less durable and durable. Thick discs have a large resource, but perform a coarser cut.

Number and size of teeth . The number of teeth on the disk, which can vary from 8-10 to 80-90, affects two factors - the speed and quality of the cut. The more teeth the disc has, the cleaner the cut will be, but the lower the speed. The same connection exists with the size of the teeth: small ones for slow and neat cuts, large ones for fast but rough ones.

The shape of the teeth and their angle of inclination . The shape of the teeth determines the applicability of this disc for carrying out a particular operation, cutting of a particular material. For example, a trapezoid tooth is suitable for cutting wood, chipboard, plastic, non-ferrous metals. Concave is designed for cutting materials with single-layer or two-layer coating, such as laminate, as well as abrasive materials. A replaceable tooth (the tips of the teeth are beveled alternately to the left, then to the right side) provides a clean cut of wood, plywood, MDF, etc.

, i.e. the deviation of the surface of the cutting edge from the radius of the saw blade. Drives with a positive inclination (from 5 ° to 20 °) are generally recommended to be used for the longitudinal saw of wood and wood-containing materials. They can also be used on miter saws, but the cut will be rough, albeit fast, with an increase in productivity and a drop in quality proportional to an increase in the angle of inclination of the teeth.

Disc teeth with positive inclination.

A negative slope (-5 °) is ideal for trimming: the process slows down, but the cut turns out clean. A zero inclination angle of the teeth indicates that this disc is designed to work with hard materials, for example, with metals.

Disc teeth with negative tilt.

Disk rotational speed . Permissible rotational speed can vary from 3800 to 23800 rpm. / min It should be remembered that the number of revolutions indicated on the disc must necessarily be greater than the speed of rotation of the miter saw shaft, otherwise in the process of operation the disc may simply break. Your safety is directly dependent on compliance with this rule!

Basic information about the disk - landing and outer diameter, thickness, number of teeth, purpose, maximum allowable number of revolutions - can be learned from the marking on the canvas. However, even with this information, it is not always easy to find what you need, among a huge variety of disks on store shelves, so do not neglect the advice of experts. Among the sellers of stores such are not often - it is better to ask for help from a person who has real experience with such equipment.

If there wasn’t a professional who could help you with your choice, you should follow two simple rules: first, use only those discs that are recommended for this model of miter saw, and second, cut only the material for which this disc is intended.

Today the market is full of so-called "universal" disks, which, according to advertising, can be installed on any type of tool and cope equally well with various materials and tasks. Alas, in this world in general there is nothing universal, and universal equipment for cutting-sawing power tools and even more so. Otherwise, manufacturers would not waste time and huge money on calculations, testing and production. Remember that the "left" disk can simply not withstand the loads created by the tool. And this means that a user who decides to use a tooling that is not recommended by the manufacturer also risks expensive equipment and, most importantly, his own health.