Power consumption
The total power consumed by a mains-powered electric tool (see "Power Source"). It is considered the main criterion for assessing the overall capabilities of a particular model: more power allows you to achieve more speed and/or torque. However a more correct parameter for such an assessment is useful (working) power, but it is far from always indicated, and tools of the same type with similar power consumption usually do not differ much in terms of working power. In addition, data on power consumption also allows you to estimate the load on the power grid or other power source; in some cases this is unnecessary.
As for specific figures, for different types of tools, the characteristic power values will be different. For example,
from 750 to 1000 W is considered a very solid indicator for a screwdriver, while for classic drills this is an average value, among such devices there are options even for
1.5 kW or more. Detailed recommendations on choosing a tool for this parameter can be found in special sources. We only note that it does not always make sense to chase the maximum values high power noticeably affects the dimensions, weight and price of the unit, despite the fact that it is far from always required.
Rotation speed
The speed of rotation of the working nozzle provided by the tool.
If a single number is indicated in this paragraph (for example, 1800), it can be either a standard, constant, or maximum rotation speed. This refers to the maximum speed if the tool has more than one speed (see "Number of speeds") and/or a speed controller (see "Functions"). In turn, two or three numbers through an oblique line (for example, 1100/2300/3400) are indicated only for models that have the corresponding number of individual speeds. Each of these numbers indicates the standard (and in the presence of a speed controller — the maximum) number of revolutions at one of the speeds.
Anyway, when choosing a tool by the number of revolutions, it is worth considering both its general type (see "Device") and the specifics of the intended work. Detailed recommendations on this matter are quite extensive, it makes no sense to give them in full here — it is better to turn to special sources. We note only a few general points. So,
high -speed drills nowadays are considered to be drills capable of delivering more than 3000 rpm. In general, high speed contributes to productivity, but there is also a downside: increasing the speed (for the same power) reduces torque — accordingly, the efficiency of working with stubborn materials and large diameter nozzles decreases. Therefore, it makes sense to specifically look for a "high-speed" tool only if speed is of key impor
...tance; it doesn’t hurt to make sure that the model you choose can provide the required efficiency and torque.Reverse
Type of
reverse provided in the design of the tool.
The reverse allows you to switch the direction of rotation of the nozzle; see "Functions" for details. It also indicates the type of switch responsible for this function. The varieties of such switches nowadays are very diverse:
slider,
flag,
brush on the engine,
on the start button,
gyroscopic,
on the keyboard toggle switch, and also combined with
a flow switch or
ratchet mechanism. Here is a detailed description of each of these varieties:
— Crawler. Switch in the form of a slider with two opposite positions. Usually, it moves in the direction "back and forth" relative to the tool chuck — this format is considered the most practical. The sliders are quite simple and at the same time convenient and visual, especially when used in screwdrivers and wrenches: by moving forward (away from you), the direction of rotation is set to twisting, by moving backward (toward yourself), respectively, to unscrewing. However, such devices are widely used in other types of instruments (see "Device") and are generally the most popular option nowadays.
— Combined with the flow switch. The most popular type of reve
...rse in pneumatic tools (see "Power Source"); not found in other models. The flow switch itself is actually a speed controller, most often in the form of a distinctive rotary knob or lever. And if this regulator is combined with a reverse, this means that it can deviate from the neutral position in two directions, and the direction of rotation will depend on which direction the flow switch is shifted.
— Flag. A switch in the form of a flag, usually installed above the start button and thrown to the right and left. One of the advantages of a checkbox is that it is right at your fingertips and can be toggled with almost no unnecessary movement (which is not always available for a slider). On the other hand, this option is mainly suitable for drills, and in screwdrivers and wrenches, the checkbox is not as intuitive as the same slider. And in general, this type of reverse for a number of reasons is much less common.
— Brush (on the engine). Reverse switch installed directly in the tool motor and based on the use of a special movable brush holder. By changing the position of the brushes in the motor with the help of such a mechanism, it is possible to change the direction of its rotation. One of the key advantages of this method is that it allows you to achieve maximum power in any direction of rotation without any special tricks. In addition, such an adjustment has a positive effect on the engine resource. On the other hand, brush switches are quite complex and expensive, and therefore are installed mainly in a powerful professional tool.
— On the start button. Reverse switch combined with start button. Such a combination button is usually made in the form of a "rocker", and the direction of rotation depends on which side of the rocker the user pressed; pressing the same button immediately starts the engine. This design allows you to easily and quickly change the direction of rotation — for this you do not need to be distracted by individual switches, just move your finger slightly and press the other half of the start button. This is especially convenient for screw and wrench drivers, as well as screwdrivers; in fact, most of the models with this type of reverse belong to these types.
— On a keyboard switch. The control method, in many respects similar to the reverse on the start button described above, also uses a rocker switch. The key difference is that in this case the direction switch is made separately from the start button — that is, the user must first select the direction of movement, and then press "start". This option does not have any particular drawbacks, but it also does not differ in convenience, and therefore it is extremely rare.
— Gyroscopic. A rather rare and specific type of reverse, found exclusively in screwdrivers (see "Type"). In fact, there are no external switches in such a tool — instead, a built-in gyroscope is used to track body rotations. Accordingly, to select the direction of movement, you need to rather sharply turn the tool around the longitudinal axis in the appropriate direction and smoothly return it to its original position (speed can be adjusted in the same way — for example, the farther the turn, the higher the speed will be). This control method is very simple and intuitive, but it is rather complicated in technical implementation and requires increased accuracy in handling the tool. That is why gyroscopic reverse is extremely rare nowadays.
— Combined with a ratchet mechanism. Another rather rare option, found exclusively in wrenches — mostly pneumatic, less often battery-powered (see "Power"). The ratchet mechanism, we recall, is responsible for ensuring that the working part of the tool rotates in only one direction. And the reverse is controlled through a mechanical switch, which is directly connected to this mechanism and changes its settings, setting one or another direction of rotation.Weight
The total weight of the tool is usually the device itself, without attachments. For battery models (see "Power Source"), usually, the weight is indicated with a standard battery installed; for battery-powered models, the weight can be given both with and without batteries, but in this case this point is not particularly important.
Other things being equal, less weight simplifies work, increases accuracy of movement and allows you to use the tool for longer without tiring. However, note that high power and productivity inevitably increase the mass of the tool; and various tricks to reduce weight increase the price and can reduce reliability. In addition, in some cases, a massive design is more preferable. First of all, this applies to work with a large load — for example, drilling holes of large diameter, or making recesses with impact: a heavy tool is more stable, it is less prone to jerks and shifts due to uneven material, vibration of mechanisms, etc.
It is also worth noting that specific weight values are directly related to the type of tool (see "Device"). Screwdrivers are the lightest — in most of them this figure
does not exceed 500 g. Screwdrivers and drill drivers are more "heavy": their average weight is
1.1 – 1.5 kg, although there are many lighter (
0.6 – 1 kg) and heavier (
1.6 – 2 kg or more ) models. And clas
...sic drills and wrenches have the greatest weight: such a tool must be quite powerful, so for them 1.6 – 2 kg is an average, 2.1 – 2.5 kg is above average, and many units weigh more than 2, 5 kg.Wood drilling max. ⌀
The largest diameter of holes that the tool can make when drilling with a conventional drill in wood.
The larger the hole diameter, the higher the resistance of the material, the more power the tool must provide and the higher the load on it. Therefore, the maximum allowable drilling diameter must not be exceeded, even if the chuck allows you to install a thicker drill bit — this can lead to tool breakage and even injury to others.
It is worth noting that some types of wood can have a fairly high density, and for them the actual allowable drill diameter will be, accordingly, less than the claimed one. However, this is true mainly for exotic breeds, which are extremely rare in our area.
Concrete drilling max. ⌀
The largest diameter of the holes that the tool is capable of making when drilling with a conventional drill in concrete. It is worth considering that in this case we are not talking about reinforced concrete — this material requires special methods of influence (ideally, the use of diamond crowns).
The larger the hole diameter, the higher the resistance of the material, the more power the tool must provide and the higher the load on it. Therefore, the maximum allowable drilling diameter must not be exceeded, even if the chuck allows you to install a thicker drill bit — this can lead to tool breakage and even injury to others.
