Comparison Ryobi R18IW3-0 vs AEG BSS 18C 12Z-0

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.

Torque is the maximum force with which this model is capable of turning the working nozzle.

Higher torque gives more options, it allows you to cope with complex tasks such as drilling in hard materials, unscrewing stuck screws and nuts, etc. On the other hand, a lot of force requires corresponding power — and this, in turn, affects the dimensions , weight and cost of the tool itself, and also puts forward increased power requirements (mains power, battery capacity or pressure / compressor performance). And for some tasks, excessive torque is basically unacceptable, so for maximum versatility, it is desirable to have torque control — and this affects the cost even more. And the more steps, the more optimally you can configure the tool to perform a particular type of work. So the general rule is this: when choosing, it is worth considering the specifics of the planned work, and not chasing the greatest working effort.

Detailed recommendations on choosing the optimal torque for different types of tools (see "Device") can be found in special sources. Here we note that it is of key importance primarily for screwdrivers, although it is also given for other types of tools. At the same time, in the “weakest” models, the maximum working force does not exceed 15 Nm, in the most powerful ones it is more than 150 Nm.

The type of gearbox provided in the design of the tool.

A gearbox can be simply described as a mechanism that transmits rotation from an electric motor to a chuck. In this case, usually, the rotation speed decreases, due to which the torque increases. Different types of gearboxes differ just in the number of speeds that can be obtained at the output. The simplest variety of such mechanisms is single-speed, they are as simple as possible, compact and reliable. At the same time, in a tool with a 1-speed gearbox, speed control may well be provided — due to electronic circuits that allow you to adjust the engine speed. On the other hand, reducing the actual speed by means of electronic control does not lead to an increase, but to a decrease in torque.

More advanced are multi-speed gearboxes, usually having 2 to 4 speeds. Such mechanisms are analogous to a gearbox in a car: the speed in them is regulated by changing the gear ratio, so that a decrease in speed leads to an increase in torque, and vice versa. Such an adjustment is considered more practical than the electronic one described above; the downside is the complexity and high cost of multi-speed gearboxes.

The number of speeds provided in the design of the tool.

First of all, let's clarify that "speed" in this case means high-speed mode. The number of revolutions at each "speed" can be either fixed or adjustable (if there is an appropriate regulator — see "Functions"). Thus, the presence of several speeds can have different meanings. In some models, changing the speed mode is the only option for adjusting the speed; in others (if there is a separate speed controller), changing the mode sets only the maximum speed of rotation of the nozzle, and its actual speed is smoothly changed by the controller (which may also have its own, additional speed limiter).

As for the specific number of speed modes, in many models it is only one. Accordingly, the revolutions in such a tool either do not change at all, or are controlled only by the mentioned regulator; this is often sufficient for simple tasks. However, 2-speed tools are also very widespread — this design provides additional tuning options and at the same time remains relatively simple and inexpensive. And in fairly advanced models, you can find three, or even four or more speed modes; in some cases, this number reaches 8 or even more, which allows you to use speed switching as a full-fledged speed controller.

When choosing according to this characteristic, it should be...taken into account that, other things being equal, a larger number of speeds gives more features for setting operating parameters, but complicates the design and increases its cost.

— Impact mode. Ability to work in the so-called shock mode. Usually, this mode is turned on and off at the request of the user, and its meaning and features may be different, depending on the type of instrument (see "Device"). So, in drills, strikes are carried out along the axis of the drill, and their frequency is usually several thousand per minute — this has a positive effect on productivity and allows you to more effectively cope with hard, dense materials (although such a drill can not be replaced anyway). In turn, in screwdrivers and wrenches, it would be more correct to call the impact mode pulsed: in this format of operation, the tool nozzle does not rotate uniformly, but in separate jerks, usually at a frequency of about 3K per minute. It also improves work efficiency, which is especially useful when driving self-tapping screws into dense material and unscrewing old, “stuck” fasteners.

— Engine brake. A device that additionally slows down the engine when the tool is turned off. The engine itself (and, accordingly, the working nozzle) after turning off can rotate for quite a long time by inertia; the brake stops this rotation almost immediately, so you do not have to keep the tool on weight for too long.

— Power button lock. A function that allows you to lock the power button in the pressed position. Usually, it looks like an additional button insta...lled either on the start key itself or not far from it. This function is very convenient in situations where the tool has to be used for a long time without interruption — for example, when drilling several dozen holes at once: it is easier to fix the start button in the on position than to keep it pressed all the time, additionally straining the finger on the working hand. And the lock is turned off, usually, in the simplest way — for example, by briefly pressing the same start button.

— Speed controller. Possibility to additionally limit the revolutions of the tool. By itself, smooth adjustment is available in almost all modern models: the harder you press the start button, the higher the speed. This allows you to directly "on the go" adjust the mode of operation of the tool to the specifics of the situation. And this regulator allows you to set the maximum speed of rotation, so that even when you press the button “to the stop”, the speed of the working nozzle does not exceed the specified value. This function is indispensable for some jobs that require precision — in particular, when processing delicate materials, for which too high a speed is fraught with damage.
Separately, we emphasize that the presence of a speed controller has nothing to do with the number of speeds (see above). For example, a tool may well have several speed modes, in each of which the speed can be further limited using a regulator.

— Maintain momentum. A feature that allows you to maintain a constant speed of rotation of the nozzle, regardless of the load on it. Without special adjustment, at a constant engine power, the rotational speed inevitably drops with increasing load and increases with a decrease. And the revs control system monitors the resistance on the nozzle and, if necessary, changes the power in such a way that the rotation speed remains constant. This has a positive effect both on the quality of work and on the service life of the nozzles and the entire tool.

— Electronic engine protection. A system that protects the engine from critical overloads — for example, in the event of a jammed drill — and overheating. If the motor load or motor temperature is exceeded, the power to the instrument is automatically turned off to avoid damage to the instrument.

— Brushless motor. The presence of a brushless (brushless) motor in an electric tool. Such motors are noticeably superior to traditional collector motors in terms of efficiency, which can significantly reduce energy consumption without sacrificing power; this is especially important for cordless tools (see "Power Source"), where this feature is predominantly found. In addition, brushless motors are quieter and produce virtually no sparks during operation, making them perfect for working in high fire hazard environments. Their main disadvantages are traditional — the complexity of the design and high price.

— Safety clutch. A device that protects the engine from damage during a sharp increase in load (for example, due to jamming of the drill). In such cases, the safety clutch disconnects the motor shaft from the tool chuck, avoiding overloads. Note that such devices can be both reusable and disposable — the latter are destroyed when triggered, and to continue working, you will need to install a new clutch.

— Backlight. The built-in lamp for illumination of a place of work. This feature can be useful both in the evening/night time, and in hard-to-reach places where there is little penetration of outdoor lighting, as well as in situations where this lighting is too dim. Note that in addition to built-in light sources, modern tools can also be equipped with separate flashlights; for more details about them, see "Complete set".

— Display. Own display, which can display various information about the operation and status of the device — for example, the torque or rotation speed set in the settings, and in battery models, there is also a battery charge indicator. Such a screen provides additional convenience and visibility, however, in general, this is a rather specific function that is extremely rare in modern power tools — for example, a speed or torque indicator can be provided directly on the regulator, and a conventional LED can be provided as a charge indicator, giving signals by blinking or colour change.

— Synchronization with a smartphone. The ability to connect the instrument to a smartphone or other gadget (such as a tablet) via Wi-Fi or Bluetooth. Such a connection is usually used to adjust operating parameters such as speed or torque; doing this through a mobile application is often more convenient than through the controls on the instrument itself. And some models with this function also allow you to set password access: the tool simply will not respond to the start button until the correct password is entered on the control gadget.

— Built-in bubble level. Built-in device to control the angle at which the tool is located to the horizon. As in ordinary levels, the role of the scale in such devices is played by a sealed flask with marks applied to it, containing a brightly coloured liquid and an air bubble. By the position of this bubble relative to the marks, the position of the entire tool is determined — namely, its correspondence to the vertical, horizontal, or pre-set tilt angle (the latter option, however, is almost never found in the built-in levels). At the same time, purely hand tools usually provide a single-axis level that reacts only to deviation from the horizontal forward or backward, and models with the ability to mount on a rack (see below) can also have a circular level that controls compliance with the vertical and determines deviations from it in any direction.

— Revolving mechanism for bits. A mechanism for storing and quickly changing bits used in tools for the corresponding purpose — mainly screwdrivers, but also some screwdrivers (see "Device"). In accordance with the name, the main part of the mechanism is a drum like a revolver, in the compartments of which the bits are stored. The mechanism is located behind the cartridge, and the choice of bits usually occurs as follows: you need to pull back a special casing or handle (if at that moment there was another bit in the cartridge, it will return to the drum), by turning the drum, select the compartment with the desired nozzle, and then move the casing / handle to its original position by pushing the nozzle out of the drum into the chuck. This feature significantly speeds up and simplifies the replacement of nozzles, and also reduces the risk of losing them. On the other hand, the revolving mechanism significantly affects the price and weight of the tool, and its capacity is usually limited to 6 – 8 nozzles. Thus, such a tool is usually also equipped with an adapter for installing bits in the traditional way, from the outside of the cartridge.

— Water cooling(coolant). The tool has a coolant — a liquid cooling system (most often plain water) supplied to the working nozzle using a built-in pump. Such a system performs several functions at once. Firstly, it actually cools the nozzle, preventing damage due to overheating. Secondly, the liquid somewhat reduces friction at the point of contact, further reducing the load on the nozzle and increasing its durability. Thirdly, water absorbs dust generated during drilling, this dust does not fly into the air and does not enter the lungs of people around; and cleaning up after work is much easier. On the other hand, water cooling systems are quite expensive and bulky, and with relatively simple work and low loads, it is quite possible to do without coolant.

— Soft start. A function that provides a smooth spin-up of the tool motor, with relatively little acceleration. This is achieved by limiting the starting current. Without such a limit, the current drawn by the motor at the time of starting can be quite high, causing the motor to start very abruptly, which increases the risk of letting go of the tool. In addition, current surges can lead to overloads in the network used for power. Soft start allows you to eliminate these phenomena to some extent. Note that it is used only in mains-powered models — the motors in cordless tools are not so powerful that they have the actual “troubles” described for them.

The name of the battery platform supported by the device. A single battery platform is used to combine various power tools of the same brand into one line (screwdriver, grinder, circular saw, etc.). Devices on the same platform use interchangeable batteries and chargers. Thanks to this, for example, there is no need to select a battery for each individual model of a power tool, because one purchased as a spare battery can be used in various power tools, depending on the situation or as needed. Batteries of the same platform basically differ from each other except perhaps in capacity.

Battery models compatible with the tool.

When choosing a tool, this information is relevant mainly for models without a battery in the kit (see "Complete battery"). For tools that come with batteries, the battery model is more of a reference—it's mostly "for the future" if a spare or replacement battery is needed. However, this data can also be useful in the selection process — for example, to assess compatibility with an existing battery on the farm, or to find detailed data on compatible batteries and determine how they meet your requirements (in particular, there are formulas that allow you to determine the time of continuous operation from a specific battery; these formulas can be found in special sources).

Method of attaching the battery to the tool.

— Clip. With this fixation, the battery is fully or partially inserted into the handle of the tool — like a clip (magazine) of a pistol, hence the name. This method is convenient in that when installing the battery, there is a minimum of unnecessary parts outside; and small low-power batteries can completely hide inside the case without affecting the dimensions of the tool. On the other hand, for powerful and capacious power supplies with significant dimensions and weight, the clip-on mounting method is poorly suited for a number of reasons. Therefore, this option is found much less often than sliders, and mainly among low-power instruments.

— Slider. This method involves the use of special guides — a kind of "sled" along which the battery moves during installation and removal; such "sledges" are usually placed at the bottom, at the end of the handle. The slider is suitable for batteries of almost any size and weight, including the most powerful and heavy batteries used in power tools. In addition, it does not have such severe restrictions on the shape of the battery as a clip-type mount. So most modern cordless tools use sliders, and for medium and high power units, this option is almost standard. Its disadvantages include perhaps the moment that the installed battery is located outside the tool and somewhat increases its dimensions. However, t...his point most often turns out to be unprincipled — especially for powerful and heavy devices that are initially quite large.