Comparison Grand DA-12U Pro vs Grand DA-12M

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.

The number of beats per minute provided by a tool that supports the corresponding mode.

For more information about this mode, see "Functions", here we note that it can be provided both in drills and in screwdrivers and wrenches (see "Device"), and the meaning of the impact mode in these varieties is somewhat different. Therefore, the speeds differ: many drills are capable of delivering about 48,000 beats / min, or even 64,000 beats / min, while in screwdrivers and wrenches, 3200 beats / min are considered “classics of the genre”, and values above 3500 beats / min are practically do not meet.

The general meaning of this indicator is also directly related to the type. So, among drills, the difference in chiseling speed can be quite large. With these tools, more strokes improve overall productivity and efficiency, while fewer strokes improve accuracy and reduce the risk of damaging delicate materials. In screwdrivers and nutrunners, high speed also contributes to overall efficiency, but for most of these tools, the differences in this indicator are not significant enough to be noticeable in practice.

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 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.

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.

The largest diameter of holes that the tool is capable of making when drilling with a conventional drill in metal.

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.

Also note that the drilling diameter for metal is usually indicated based on medium hard steel and other similar materials. For metals and alloys that have a significantly higher hardness and density, the allowable drill thickness will be less; however, such situations occur infrequently, and if you wish, you can find out about the features of working with various alloys x in special sources.

— Impact Mode. The ability to work in the so-called impact mode. Usually, this mode is switched on and off at the user's discretion, and its meaning and features can vary depending on the type of tool (see "Device"). For example, in drills, impacts are made along the drill axis, typically at a rate of several thousand per minute, positively affecting performance and allowing more efficient handling of hard, dense materials (although such a drill still cannot fully replace a rotary hammer). Conversely, in screwdrivers and impact wrenches, the impact mode would more accurately be called impulse: in this work format, the tool's attachment rotates in separate jerks, usually at a frequency of about 3,000 per minute. This also enhances work efficiency, which is especially useful when screwing screws into dense material and loosening old, "stuck" fasteners.

— Power Button Lock. A function that allows the power button to be fixed in the pressed position. Usually, it has the form of an additional button installed either on the main trigger or nearby. This function is very convenient in situations where the tool has to be used for a long time without breaks — for instance, when drilling several dozen holes: it is easier to fix the start button in the on position than to hold it down constantly, further straining the finger on the working hand. And the lock is usually turned off in the simplest way — for exampl...e, by briefly pressing the same start button.

— Speed Control. The ability to additionally limit the tool's speed. Smooth adjustment is present in almost all modern models: the harder the start button is pressed, the higher the speed. This allows you to adjust the tool's operation mode on the fly to suit the situation's characteristics. And this regulator allows setting the maximum rotation speed, so even when the button is pressed "to the limit," the working nozzles' speed does not exceed the set value. This function is indispensable for some tasks requiring precision — notably when handling delicate materials where too high a speed is fraught with damage.
It is important to note that having a speed controller is not related to the number of speed settings (see above). For example, a tool may very well have several speed modes, each of which can have its speed further limited by the controller.

— Speed Maintenance. A function that allows maintaining a constant rotation speed of the nozzle, regardless of the load on it. Without special regulation, at the engine's constant power, the rotation speed inevitably decreases with increased load and increases with decreased load. And the speed maintenance system monitors resistance on the nozzle and, if necessary, changes power so that the rotation speed remains constant. This positively affects both the quality of work and the longevity of the nozzles and the entire tool.

— Brushless Motor. The presence of a brushless (commutatorless) motor in the power tool. Such motors significantly surpass traditional commutator motors in efficiency, which allows for a noticeable reduction in energy consumption without sacrificing power; this is especially important for battery-powered tools (see "Power Source"), where this feature is predominantly found. Besides, brushless motors are less noisy and practically do not produce sparks during operation, making them ideal for work in increased fire hazard conditions. Their main drawbacks are traditional — complex design and high cost.

— Lighting. Built-in light for illuminating the work area. This function can be useful both in evening/night time and in hard-to-reach places where outside lighting poorly penetrates, and also in situations where this lighting is too dim. In most cases, it is implemented with a single LED that lights the working area in front of the tool.

— Ring Lighting. An advanced lighting system where LEDs are arranged around the chuck, allowing for even illumination of the drilling or screwing area. Thus, light falls not from the side but precisely around the working part, reducing interference from shadows cast by the body, hand, or bit. This helps start drilling more accurately, hit the slot with the bit more neatly, and work more confidently with small fasteners. In practice, ring lighting is especially convenient when assembling furniture, installing shelves, working under a sink, or repairing places where little general light penetrates.

— Display. Own display on which various information about the work and state of the device can be displayed — for example, the torque set in the settings or the rotation speed, and in battery models — also a battery charge indicator. Such a screen provides additional convenience and visibility; however, overall, it is quite a specific function that is extremely rare in modern power tools — for instance, speed or torque indicators can be provided directly on the regulator, while a simple LED that signals by blinking or changing color can be used as a charge indicator.

— Smartphone Synchronization. The ability to connect the tool to a smartphone or other gadget (for example, a tablet) via Wi-Fi or Bluetooth. Such a connection is usually used to adjust work parameters like speed or torque; doing this through a mobile app is often more convenient than through the controls on the tool itself. And some models with this feature allow you to set access via a password: the tool simply will not respond to the start button until the correct password is entered on the controlling gadget.

— Built-in Bubble Level. An integrated device for controlling the angle of the tool relative to the horizon. As with regular levels, the scale's role in such devices is played by a sealed vial with marked lines containing brightly colored liquid and an air bubble. By the position of this bubble relative to the marks, the entire tool's position is determined — namely, its alignment with vertical, horizontal, or a predetermined tilt angle (the latter option is virtually never found in built-in levels). In manual tools, usually a single-axis level is provided, reacting only to deviations from horizontal forward or backward, while models with the ability to be mounted on a stand (see below) may also have a circular level, checking vertical alignment and detecting deviations from it in any direction.

— Bit Compartment. A storage place for interchangeable attachments directly in the tool's housing, handle, or battery base. Most often, it is a simple slot or holder for one bit, so the most frequently used attachment is always at hand and does not get lost during work. Less commonly, there is a drum compartment or built-in magazine for several bits.

— Water Cooling (SOL). The presence of SOL in the tool — a liquid cooling system (most often plain water) supplied to the working nozzle using a built-in pump. Such a system performs several functions simultaneously. Firstly, it actually cools the nozzle, preventing damage due to overheating. Secondly, the liquid slightly reduces friction at the contact point, further reducing load on the nozzle and increasing its durability. Thirdly, water absorbs the dust formed during drilling, preventing it from dispersing into the air and entering the lungs of surrounding people; and cleaning after work is significantly simplified. On the other hand, water cooling systems are quite expensive and bulky, and for relatively simple tasks and low loads, it is quite possible to do without SOL.

- Corner nozzle. A nozzle that allows you to rotate the axis of rotation of the cartridge by 90 ° relative to its original position. Such a device is indispensable for making holes, as well as twisting and unscrewing fasteners in some hard-to-reach places (for example, in narrow grooves or a profile).

- Eccentric nozzle. Replaceable nozzle designed to shift the axis of rotation of the cartridge slightly away from its original position. In this case, the direction of the axis remains the same. Like the corner nozzle, such a device is intended mainly for working in certain hard-to-reach places (in particular, near walls and edges of workpieces).

- Additional handle. A modern tool, even a relatively low-power one, can be quite massive, and for maximum accuracy and reliability it may be necessary to hold it with two hands at once. Using an additional handle for this is more convenient and safer than looking for a place to grip on the body. The handles themselves are usually mounted near the cartridge perpendicular to the axis of rotation and may have different design features.

- Depth stop. A device that allows you to limit the depth of drilling. The most popular version of such a limiter is a rod in a special mount, installed parallel to the drill. Before starting work, this rod is shifted so that when the desired depth is reached, its end rests on the surface of the material,...preventing the drill from moving further.

- Store nozzle. It looks like a kind of store or disk, into which a tape with self-tapping screws is “charged”; and a special block is installed in front of the cartridge, designed to supply self-tapping screws. This design allows you to tighten the screws as quickly as possible and without unnecessary movements: just load the tape from the magazine into the feed unit, start the engine and alternately press the working part of the tool to the desired points on the material.

- Lantern. A classic flashlight for illumination in low light conditions, in contrast to the built-in illumination system, is a separate device. Such a separate device is not very convenient to hold in your hand during work - in such cases you can’t take the tool with both hands, and this creates problems in some situations. On the other hand, often the situation allows you to put or hang a lantern without taking up your hands; and sometimes in this way you can even organize the lighting more successfully than using the built-in backlight. In addition, the flashlight can be used independently.

- Case (bag) included. The presence of a case or bag in the delivery set of the drill. Cases are usually called hard suitcases; bags, unlike cases, are soft, which allows them to be packed more tightly together with other things, but reduces the degree of protection. In any case, this feature makes the tool more convenient to store and carry: the complete bag or case is optimally suited for this model, in addition, they can hold drills, spare batteries and other additional accessories.

- Rack. Mostly professional drills for diamond drilling are completed with racks(see "Purpose"). This design is a stand (base) with a guide rail fixed on it, along which the tool can move using a special mechanism. According to the fastening of the rail, the racks are divided into two types:

• Non-inclined stand. A structure with a rigidly fixed rail, which is usually located vertically, perpendicular to the base; accordingly, the axis of rotation of the installed tool also remains always vertical. Such racks have more limited capabilities than inclined ones. On the other hand, they are simpler, cheaper and more reliable (there is no movable mount in the design that can become loose); and for most work, the vertical position of the tool is fine.
• Tilt stand. Stands in which the rail is fixed on a swivel mount and can deviate from the vertical at a certain angle. Accordingly, such a device allows you to direct the crown not only vertically, but also at an angle; this can be important for some non-standard tasks. On the other hand, a movable structure is more complex, expensive and less durable than a fixed one; therefore, it is worth paying attention to this option if the possibility of inclined drilling is fundamental for you.

- A set of drills. The presence of drills in the kit eliminates the need to purchase them separately and allows you to use a drill (or other tool with drill functions) right out of the box. True, the specific assortment of drills can be different - besides, it is often an entry-level set of 5 to 7 devices for the simplest tasks like drilling wood. However, even such a set will be useful if the tool is purchased for domestic use or simple work that does not require specialized nozzles. We also note that such equipment is especially convenient when buying a “first tool for a beginner”, when there are no drills on the farm yet and one way or another you will have to buy them.

- A set of bits. Bits, we recall, are nozzles in the form of screwdriver heads, which are also used in screwdrivers. As in the case of drills, the presence of such nozzles in the kit eliminates the need to purchase them separately and makes it possible to use the tool immediately after purchase. The specific set of bits is worth specifying further, but most often it includes at least flat and cross bits in a fairly large variety of sizes. And in general, such sets are quite extensive - even in relatively inexpensive tools, the number of complete bits can be measured in tens.

- Equipment. The term "equipment" means at least several types of working nozzles, and sometimes additional accessories. For example, if such equipment is indicated for a drill-driver, then this model is almost guaranteed to be equipped with both drills and bits (and possibly more specific accessories). A specific set of equipment should be specified separately.

- Extension. The purpose of such an accessory is clear from the name: it allows you to increase the working length of the tool. In other words, when you install an extension bat or other equipment, it is further from the body; the extension itself is made quite thin. This accessory is used mainly in models with the functions of a screwdriver or wrench: it allows you to reach deep-seated fasteners that are inaccessible in the usual configuration. And in many models, the extension cord is also made flexible, which further expands its capabilities.

- Magnetizer. Device for magnetizing bolts, screws and other similar fasteners. Found in individual screwdrivers; the working tooling of such tools is also made of magnetic material, due to which the magnetized fastener effectively “sticks” to the tooling and does not need to be supported separately.

- Case insert. Interchangeable insert (or several inserts) to adjust the complete case to the specific situation. For example, a regular insert can only have space for a tool and a charger, and a replacement one can also accommodate a second spare battery. Specific features should be specified separately.

- Charger(charger). A device for charging the batteries used in the tool with the appropriate power supply. For models supplied with such a device, the charger model may be additionally specified in the characteristics. This information can be useful not only for finding a spare or replacement charger, but also in case the household has other cordless tools and / or batteries for them. The fact is that many manufacturers nowadays use universal batteries that are compatible with a whole set of tools from the same brand; so, for example, a complete charger for a drill may be quite suitable for a cordless grinder from the same manufacturer.
On the other hand, a lot of modern cordless tools come without a charger at all. This option will be optimal, first of all, if a compatible memory is already available, and there is simply no need to overpay for a second device. In addition, the lack of a charger will be appreciated by those who want to choose this accessory separately, without relying on the manufacturer's decision.


Note that the above list is not complete - modern tools can be supplied with other additional items, including very unexpected and original ones - like a fitness tracker or even a radio-controlled car.