Cordless drill-screwdriver: a quick way to fix all connections
There has long been no need to tighten the screws with a hand drill or screwdriver. Now, in everyday conditions, a cordless drill-screwdriver becomes an assistant, which is a compact and convenient device for operation. Manufacturers offer models with different technical characteristics. Therefore, to begin with, it is important to determine the basic requirements that the device must meet, and then plan the purchase.
Why choose a cordless screwdriver: the main types of device, operating rules
Before purchasing a product, it is necessary first of all to determine the main goals that need to be solved with a screwdriver in production or in domestic conditions. The main directions where the tool is used:
- mounting or dismantling of fasteners;
- more reliable tightening of screws, dowels, anchors or other elements;
- making holes in soft or hard materials;
- thread cutting;
- preparation of building solutions that require mixing.
In most cases, a screwdriver is used to solve several tasks at once. Therefore, first you should study the technical characteristics of the screwdriver. Depending on the field of application , the tools are divided into 2 large groups:
A distinctive feature of household tools is low power and a small motor resource. They are considered suitable for working with soft material:
- a tree;
- MDF and CHIPBOARD;
Important! Household screwdrivers are not designed for long-term use. The main directions are furniture assembly, installation of locks, fixing shelves, blinds, etc.
A professional tool is designed for a longer working time than a household one. So, you can operate the screwdriver daily for 5-8 hours with short breaks and at the same time not be afraid that the device will fail or overheat. The tool is also used for unscrewing /screwing, while most models are equipped with the function of drilling various materials:
- a tree.
You need to understand that to work with concrete, you need to purchase shock cordless screwdrivers designed for solid materials.
Which cordless screwdriver is better, based on the technical characteristics
According to the method of obtaining power , the devices are divided into 2 groups:
Useful advice! If you want to figure out which screwdriver is better – battery or mains, you need to take into account that the first option is mobile, so it can be used without a 220 V network, and the second one works only from a power outlet.
An important advantage of a cordless screwdriver is that it is powered by low voltage and does not pose a danger to the user even in the event of a breakdown. When buying, it is important to take into account the type and capacity of the battery, because it will depend on the duration of use without recharging.
For convenience, you should also understand the basic concepts. So, a drill is considered a tool equipped with a drilling function. The devices are characterized by the presence of a three-cam cartridge on the spindle, installed in the foreground. It is from the qualities and technical characteristics of this element that the maximum size of the drilled hole and the durability of the device will depend. The presence of a cartridge distinguishes drill-screwdrivers from other devices that are equipped only with a hexagon hole.
A distinctive feature of the screwdriver is an integrated adjustable safety clutch, which is adjusted depending on the required tightening level of the fastener. Another important feature is the ability of the gearbox to shift gears, which allows you to increase the speed and torque of the axis.
Depending on the brand, screwdrivers with the drill function have a large number of differences, which consist in a variety of secondary or main working units.
The best cordless screwdrivers depending on the type of battery used
To understand the question of which is the best cordless screwdriver for home or professional work, you need to familiarize yourself with the features of the battery. The cost of the goods and the durability of the work depend on this criterion. All models of drill-screwdrivers are equipped with one of the types of mobile batteries:
- nickel-metal hydride;
Most of the modern tools are equipped with lithium-ion batteries, as they are characterized by the longest service life and practically have no disadvantages. Lithium batteries, unlike other types of batteries, do not lose energy efficiency at low temperatures.
Despite the large number of advantages, Li-Ion screwdrivers have certain disadvantages. The main one is the fact that the maximum operating voltage of one battery cell is within 3.7 V, but for the full use of the engine, a minimum of 10.8 V is required (an indicator equal to 18 V is considered optimal). This leads to the fact that it is necessary to use not one element, but a bunch of 3-4 batteries connected in series.
At first glance, the disadvantage is not considered significant, but in fact, such a connection method can cause uneven charging. This is explained as follows: if one battery takes on a full charge, the rest may stop charging. The problem is that the total capacity of the battery depends on the least charged element of the entire chain, and such a mode of operation has a cumulative effect.
It’s interesting! In order for lithium batteries to charge normally, it is required to use chargers that differ in the presence of balancing contacts connected between individual battery cells to intermediate nodes of the chain.
The best in the rating of screwdrivers are models that have a controller built into the charger that determines the voltage in each group of batteries. Another advantage of having a controller is that it regulates the strength and voltage, as a result of which uniform charging of all internal elements is ensured. Devices with lithium batteries will cost more than, for example, tools with a nickel battery.
Nickel-cadmium and nickel-metal hydride batteries: what is affected by voltage
Nickel-cadmium batteries are obsolete, but nevertheless they are still used in some models of household screwdrivers. The main advantages are:
- low cost;
- trouble-free operation at low temperatures;
- the ability to recover after a full discharge.
It is necessary to know that an inexpensive cordless screwdriver with a nickel battery will have such disadvantages:
- large weight and size;
- relative fragility, because the device is designed for 1000 cycles of full charge / discharge;
- low specific capacity – up to 2 A/h;
- fast discharge, and even in standby mode;
- environmental insecurity of the battery.
Another significant disadvantage of devices with nickel batteries is the presence of the so-called “memory effect”. This means that you can charge the battery only after full discharge, because otherwise the battery capacity will decrease by the amount of under-discharge.
Tools with a nickel-metal hydride battery are devoid of some of the disadvantages of the previous version. Firstly, they are less dangerous to the environment, and secondly, they are more compact. There is no “memory effect” in the devices, and they are endowed with sufficient specific capacity. Despite this, the products also have disadvantages:
- short-lived, because the battery is designed for only 500 full charge/discharge cycles;
- high cost compared to the nickel-cadmium version;
- difficulties associated with the ability to charge the battery only after 100% discharge.
Nickel-metal hydride batteries are most often used in household appliances. Some craftsmen who have learned at home to restore the performance of batteries after passing the maximum number of discharge / charging cycles, prefer these batteries.
Checked! To resume the operation of a nickel-metal hydride battery, you just need to solder a few new cells, and then restore the cell capacity using intelligent charging.
It should also be mentioned about such a characteristic as the battery voltage. It is generally believed that the higher this indicator, the higher the torque of the screwdriver and its power. It is important to take into account that some models are presented in the range from 3 to 36 V.
If you compare devices with different voltage, for example, 14 and 18 V, you can pay attention to the fact that they have the same torque – 70 N / m, and the difference is only in the number of elements that make up the battery. In a device with an 18-volt battery, there are more such elements, and therefore the battery capacity increases. This is what affects the cost of the instrument. Thus, before buying, you need to decide whether this characteristic is considered fundamental when choosing a device.
What type of engine can a cordless drill-screwdriver be equipped with: options for starting systems
The DC motor is the main power element of any cordless screwdriver. There are two types of parts:
About 90% of all tools are equipped with permanent magnet brush motors. Such models belong to budget screwdrivers with a simple design. The main disadvantages of this variety are:
- relatively low efficiency;
- no possibility of repair;
- limited resource.
By and large, we can say that brush motors, depending on the manufacturer, may differ in varying degrees of reliability. For example, engine cooling will be better in models that have additional windows on the body. This prevents overheating and damage to the windings. If the device has a detachable housing, this may indicate the possibility of repair work related to maintenance of bearings and replacement of unusable brushes.
Drill-screwdriver network: a universal device for screwing and drilling
Features and varieties. Advantages and disadvantages. Tips for choosing. Rating of the best network devices. Safety precautions.
Brushless motors are considered an analogue of a full-fledged collector motor, which has a multiphase power supply. But in this case, the motor has a rather complex design, although more advanced technologies are used in the manufacture of the drive unit itself. In such devices, there is a driver chip that regulates the power supply of the motor by applying the pulse width modulation (PWM) method. It is thanks to this that the voltage and current are monitored.
It’s interesting! The PWM method makes the engine quieter, and the device itself is endowed with greater efficiency. Reliability in this case is determined not by the electrical component, but by the quality of the housing, the high level of processing of seats for bearings.
Advantages and disadvantages of different types of engines
Most often, brushless motors are found in industrial tools, although professional cordless screwdrivers Bosch, Hitachi, Hilti and others can boast of such a motor. Another positive side of such a device is the smooth control of the rotation speed, which is provided by an electronic circuit.
In a brush motor, the joint operation of a bipolar transistor and a potentiometer built into the Start button allows for a relatively smooth start with no significant current supply when power is turned on. If a device with a similar structure will work for a long time at low speeds, overheating and failure of important nodal elements is possible. Most likely, you will have to change the start button as well.
In general, it can be said that in the brush device there is a constant friction of the elements against the collector contacts, which is why their abrasion is possible for several years after purchase. Other disadvantages are the constant noise of the collector engine, the probability of sparking and the creation of radio interference.
As for the disadvantages of brushless devices, this can include a complex electronic circuit of the microcontroller, which cannot be repaired independently without the necessary knowledge. Despite the fact that electronic devices are constantly getting cheaper, the cost of a brushless screwdriver still remains 2 times higher than the price of a traditional tool.
What is a reducer in a drill-screwdriver and what is it for?
The gearbox is the most reliable part of the screwdriver, which is an advanced design that does not require maintenance. It is thanks to this part that it is possible to change the rotation modes of the screwdriver shaft. The simplest gearbox is represented by one stage. In this case, the device has a monoblock structure with a motor designed to maintain a speed of 400-600 rpm. The torque in the devices is 20-30 N/m. Such gearboxes are rarely installed in battery models, they are more often used in a network tool.
Two-stage gearboxes are equipped with an additional transmission that allows the axis of the screwdriver to spin up to 1000-1500 rpm. At the same time, in such devices, the torque is reduced to 10-15 N/ m. It should not be thought that the presence of a speed switch reduces the reliability of the device. The planetary transmission switches gears using a change of gear pairs, and an increase in the torque index is provided by locking the driver, removing rotation from the crown of the clutch. For this reason, the gearshift process is absolutely painless for the gearbox itself.
It’s interesting! It is the presence of the second stage that allows you to switch the device to the “drilling” mode, which is considered an integral function for a drill.
There is another type of gearboxes equipped with a third gear, which reduces the rotation speed to 150-200 rpm and increases the torque to the maximum possible. This tool is suitable for screwing in elongated superchargers and threading.
The quality of the gearbox is determined by the components. Many consider plastic gears to be an indicator of an unreliable tool. But this is not the case at all. If high-quality high-density plastic with a special coating was used in the production, then this is considered an advantage, because even under heavy load there is no overheating of the elements. At the same time, the presence of plastic insides allows you to reduce the weight of the device.
What does the torque indicator affect and how does it change depending on the device model
If we talk about torque, it is this parameter that characterizes the potential of the electric motor, which directly rotates the cartridge shaft. The higher the index, the more dense the material can be used in the work and the easier it will be to tighten the fasteners and unscrew the sour nuts. The amount of torque varies depending on the model:
- household tools for home use – 10-15 N/m;
- professional two- and three-speed devices – 130 N/m;
- semi–professional models – 50-80 N/m.
The torque indicator should be selected based on the length and size of the fastener that you plan to work with most often.
For greater safety in the design of the best battery screwdrivers, the presence of a torque limiter has been thought out, which is a ring installed immediately after the cartridge. In order to avoid a breakdown of the screw head, as well as in order to save the bits, before you start screwing the fasteners, you need to set the required value on the ring. As soon as the device reaches the desired indicator, the cartridge stops on its own, although the engine continues to work at the same time.
Important! If the torque is set incorrectly, not only the failure of the fastener head may occur, but also its too deep sinking into the surface, which will cause the wear of an expensive bit.
The limit of the indicator is set by steps, and the divisions on the ring correspond to the rotation mode and effort. For cheap household screwdrivers, the number of steps does not exceed 10, and for professional tools it usually reaches 20.
Important components that you should pay attention to
The ability of the screwdriver to tighten fasteners is due to the presence of a special unit that also regulates the tightening force. Structurally, the element is a clutch equipped with parabolic teeth and a certain number of metal balls. The force of pressing the balls to the friction is regulated by a spring built into the structure.
As already noted, depending on the specifics of the application, the tool has 10-30 switching steps. However, it will be possible to use the regulator for its intended purpose only if the operating manual contains a table indicating the position of the coupling in relation to the current limiting torque.
Important! When using a screwdriver, it should be borne in mind that after a while the edges of the clutch are worn away, and this, in turn, leads to a decrease in the elasticity of the spring. Such wear of parts distorts the accuracy of the adjustment of the limiting coupling.
Most screwdrivers are equipped with a quick-release three-cam chuck. If you plan to work with a solid material, you should select options where the cartridge is made of high-quality materials. In inexpensive screwdrivers, the cartridge is considered a consumable part, which is replaced as the gaskets wear out.
Users most often prefer cartridges with a quick-release coupling, thanks to which it is easy to remove the cam head and put a tool with a slotted shank in its place. This version allows you to quickly switch from one operating mode to another, and also minimizes the wear of the shaft landing under increased load.
Experts recommend purchasing drill-screwdrivers equipped with a shaft locking function, which allows you to conveniently fix a nozzle with a round tail of any diameter in the cartridge. If you plan to work with a variety of materials and tools, it is better to immediately purchase a set of screwdrivers equipped with various additional functions, namely:
According to the results of the tests of screwdrivers, experts note other useful functions of the devices:
- built-in backlight;
- charging indicator.
The principle of operation of the best cordless screwdrivers for home and professional work
Cordless drills-screwdrivers are most often small and convenient devices for operation. Depending on the manufacturer and model, the tools may differ structurally, for example, the handle is often located in different places. The most common option is a handle located in the middle of the tool. But it is more convenient for drilling if the handle is slightly shifted to the back of the device.
An electric motor, a gearbox, a battery and a clamping chuck are placed under the housing. Drills with a brushless motor have a higher efficiency. The principle of operation of a battery drill looks like this:
- the engine starts, as a result of which the gearbox is activated;
- the rotation of the shaft begins, which drives the cartridge with the nozzle.
To install the drill, a toothed wrench will be required, while the coupling in the clamping chuck is tightened manually without much effort. Before starting work, it is recommended to check the amount of charge in the battery and choose a suitable nozzle for the material. After that, it is necessary to set the operating characteristics of the torque limiter.
Important! All setup work should be carried out only when the device is switched off.
Rating of cordless screwdrivers with drill function: the best manufacturers
It is not necessary to select the most expensive screwdriver for work, because there are a large number of models equipped with the necessary functions, and at the same time they have an acceptable cost. If you want the device to serve for a long time, it is recommended to give preference to proven manufacturers who produce in-demand goods. If we turn to the rating of the best cordless screwdrivers, the leading positions are occupied by such companies:
Cordless screwdriver: which is the best of inexpensive devices
Inexpensive cordless screwdrivers are considered models worth up to 5 thousand rubles. It is these options that should be selected as the first working tool for a house or cottage. If the device is used sporadically, it will last at least 10 years.
The best inexpensive cordless screwdriver is considered to be the PowerMaxx BS 2014 model by Metabo. Firstly, the product is characterized by a small weight ‒ only 800 grams, which allows you to use the device in an uncomfortable position of the hands. Secondly, the tool is equipped with a powerful 2.0 A/h battery, while the torque reaches 34 N/m. Bits and drills with a hexagon tail can also be installed in the device. The kit includes an additional battery and a roomy suitcase. Among the disadvantages, users note that it is inconvenient to remove the cartridge. The cost of a Metabo cordless screwdriver is 4900 rubles.
The Blaupunkt BPPT-001 screwdriver weighs a little more than 1 kg and has a lithium-ion battery with a capacity of 1.3 A/ h, the device voltage is 10.8 V. At idle, the maximum rotation speed reaches 1300 rpm. But thanks to the ability to choose one of the 17 presented modes, it will not be difficult to choose the optimal torque. The built-in backlight also provides convenience of operation. However, you can not work with a drill with a diameter of more than 10 mm. The cost of the model does not exceed 3 thousand rubles.
The Interskol cordless screwdriver is characterized by a nickel-cadmium battery with a capacity of 1.5 A / h, its power is 18 V. To ensure long-term operation, an additional battery is included. Full charging is carried out for an hour.
Due to the features of the battery, the DA-13/18M3 model is considered the most powerful screwdriver in the budget segment. The torque index is 36 N/m. At the same time, the device has a significant weight – 1.82 kg. Another disadvantage of the Interskol cordless screwdriver is the short battery life. The device can be operated at low temperatures, and convenient operation in the dark is provided by illumination. The twisting force is adjustable in 20 positions, which allows you to adjust the tool to work with different materials. Such a number of positive aspects also affects how much the Interskol screwdriver costs. The price of the device is 5100 rubles.
Good Chinese screwdrivers are also considered inexpensive products, for example, the FIT CD-18CSP model, which is used to perform drilling and tightening of threaded connections. The device has a high torque index (at the level of 28 N/ m), which allows you to work with dense and hard materials. Additional convenience of operation of the Fit screwdriver is provided by a quick-release chuck, which helps to replace the tooling in a couple of seconds. Other advantages:
- ergonomic handle;
- two-speed planetary gear;
- increased battery capacity;
- torque adjustment;
- electric reverse;
- price – 4700 rubles.
The best professional cordless screwdrivers Bosch, AEG, DeWalt
The word “professional” means that the device is intended for performing serious installation and construction work. The main advantages of the models are considered to be an increased rotational speed (at least 1300 rpm), high torque (more than 50 N/ m), the presence of additional functions and built-in elements.
The GSR 180-LI 1.5AH X2 model from Bosch, which is characterized by high power characteristics, is well equipped. According to reviews, the 18 volt cordless screwdriver has a two-speed motor suitable for making holes of different diameters:
- 35 mm – for wood;
- 100 mm – for metal.
Good productivity is provided by high torque – 54 N/m. With regard to the disadvantages, it is worth knowing that after six months of intensive operation, many users note the appearance of a beating, which affects the accuracy of the hole being made, which is especially critical when working with wood. The price of the Bosch 18 volt screwdriver is 7340 rubles.
The BS 18G2 LI-152C model of the German company AEG is characterized by high torque, which occupies an honorable place in the rating of professional devices. The first thing that distinguishes the AEG cordless screwdriver is a good torque indicator (50 N/m). The second important advantage is competent ergonomics. A special socket has been thought out in the instrument case, which allows you to always keep the necessary bits at hand.
In order not to increase the weight of the device, experts do not recommend storing more than 2-3 of the most frequently used bits inside. Convenience of operation is provided by a quick-release chuck, spot lighting and the ability to adjust the torque. The main disadvantages are the large weight (1.8 kg) and the cost of more than 10 thousand rubles.
The Dewalt DCD791D2 cordless screwdriver has the highest torque on the spindle – 70 N/m, which allows you to meet the requirements of any professional user. Despite the high performance and increased dimensions of individual units, the weight of the device is only 1.5 kg, and it can accelerate up to 2000 revolutions per minute. This allows you to work with viscous and difficult-to-pliable materials. An important advantage of the model is the brushless motor, which provides an increased working life. The cost is 17.6 thousand rubles.
The best battery-powered screwdrivers of various capacities
The Makita 6271DWAE cordless drill-screwdriver is distinguished by a 12-volt motor and a battery with a capacity of 2 A/h. The maximum torque is 30 N/m, while the rotation speed reaches 1300 rpm. The convenience of operation is provided by the electronic type speed adjustment. In addition, the tool is additionally equipped with a spindle locking system and a reverse. Other advantages of the battery-powered drill-screwdriver Makita:
- light weight – 1.5 kg;
- optimal balancing;
- convenient handle for working in shock mode;
- availability of a spare battery;
- reverse function;
- self-locking of the shaft.
Among the disadvantages of the 12 volt Makita screwdriver are a plastic gearbox, a crown for switching speeds, as well as the high cost of the tool at the level of 8 thousand rubles.
The 14 volt Makita screwdriver (model BDF343SHE) is equipped with a 1.3 A/h lithium battery. An important advantage of the battery is fast charging for 30 minutes. The maximum torque is 36 N/m, the rotation speed is 1300 rpm. The functions of reverse, shaft locking and speed adjustment are available, as well as among the advantages of a 14 volt screwdriver it is worth noting:
- light weight – 1.2 kg;
- attractive design;
- the ability to work with self-tapping screws of 200 mm;
- additional battery included;
- the ability to work on a single charge for up to 1.5 hours.
Of the minuses, there is a certain backlash of the cartridge and the absence of a battery level indicator. Some users note that the plastic gearbox eventually fails.
The Makita 18 volt screwdriver (model 6347DWAE), equipped with a nickel-cadmium battery, has very good reviews. The torque reaches 80 N/m, although the rotation speed does not exceed 1300 rpm. The speed is controlled by an electronic sensor, it is easy to dismantle structures using the reverse function. The weight of the device is only 1.5 kg. Other advantages of the Makita 18V screwdriver:
- easy replacement of brushes in the engine;
- high torque;
- the presence of two batteries in the kit;
- convenient start button;
- the ability to use the battery for a whole day of work.
A significant disadvantage is that, unlike the 18-volt Makita screwdrivers equipped with lithium batteries, these batteries have a “memory effect”, which, firstly, complicates charging, and secondly, significantly increases the charging time. In general, the tool is recommended for those who need to work with a large number of various fasteners.
When buying a battery tool, you should always remember that any, even the most expensive, battery is not designed to be used for more than 5 years. Nevertheless, in most cases it is much more convenient to work with the device without a cord. To choose the right model, it is important to determine in advance what requirements are imposed on the screwdriver and compare the characteristics of similar devices.