How to choose a screwdriver?

One of the basic needs of the modern man is the maximum saving of time and effort in the performance of any work. We strive to automate all possible operations that technology can perform for us. Everything should be done quickly, efficiently and with minimal effort from the person. But in order for the tasks to be successfully solved, it will not be possible to do without an appropriate tool, which means that the problem of choice becomes one of the main ones.

Twisting / twisting various fasteners is one of the most frequent operations that are periodically performed not only during the repair process, but when solving everyday household problems. Power tool manufacturers have long given the opportunity to entrust these operations to equipment, to perform them quickly, efficiently, with any consumables, in any quantities. That is why screwdrivers are one of the most common types of electrical equipment.

Professional or household?

The first question that arises when it comes to choosing a technique almost always concerns its class. With professionals who specialize in repair work, everything is clear: they need a universal tool of high power, with a good battery capacity, a large number of settings, the most complete set. With household appliances more difficult, because it is important to choose a model that is called "for all occasions", without excesses, for which you will inevitably have to pay when buying, but at the same time and with a sufficient set of features that will always be useful during the next repair.

It is important to initially decide on what exactly the surfaces will have to work, because, for example, when working with solid materials for effective work, the rotation speed should be higher than 1200 rpm, while household models make it possible to work with a maximum of 400 revolutions. As for the drilling function, the torque of a household tool is in the range of 15-20 Nm, while in professional models it averages 130 Nm, which means it can easily work with materials of any hardness.

In addition, professional and domestic models differ in operating voltage: the higher it is, the more complex tasks the screwdriver will be able to perform. For comparison: household models most often use 9.6 V, and professional from 12 V and above.

AC or battery operation

The advantages of working from the battery are obvious: the operator is not limited to the cable in his movements, no power supply is required, the distance from the outlet does not matter. Therefore, such a power tool and got so widespread, and the screwdrivers that work from the network to find more, of course, possible, but their choice is small.

As for the power of the mains and battery tools, today they are almost equal, so the problems of the latter remain higher price, the need to buy a new power source with time and a limited time of its work (although this moment is almost completely solved by buying a second battery). Also, some inconvenience in the work creates the fact that the battery is attached directly to the body, which means that it is constantly in the process of work will have to keep on weight.

If the choice fell on a cordless screwdriver, it is important to correctly determine the type of battery. Today, manufacturers offer tools with NiCd, NiMH and Li-Ion batteries. Each of them has its advantages and disadvantages, but in this case, such qualities as

• high energy intensity, since the amount of output power depends on it,
• the ability to maintain its charge and the voltage produced throughout the entire operation time,
• the ability to quickly charge the battery
• low weight
• lack of memory effect (reduction of battery capacity due to its incomplete discharge during previous work cycles).

If we compare among all the above types of batteries, then the undisputed leader in this case is Li-Ion batteries. Although they are distinguished by relatively high cost and short service life, they are far ahead of competitors in all of the above indicators.

Battery Charger

Today, pulsed and transformer chargers are offered, which respectively can "give" pulsed and direct current. As for the differences in operation between these devices, it can be noted that the transformer-type chargers have much more weight, and the pulsed ones are often equipped with electronics that allow you to monitor the operating parameters of the battery being charged.

Screwdriver equipment

Reliability and durability of the tool is always inextricably linked with its design features, the quality of the parts and spare parts used by the manufacturer. The main elements of any screwdriver is always its engine, gearbox, cartridge.

Engine

The type of engine that is installed in one or another model of the tool is essential when choosing it. In this case, the collector (brush) and non-contact (brushless) structures are offered to the consumer. If we compare them with each other, it can be noted that brushless motors

• work more smoothly
• have greater technical resource
• work much quieter
• do not require maintenance
• have greater weight and overall dimensions.
• more collector.

If the choice is made in favor of the brush design, you should pay attention to the availability of quick access to the brushes, so that during operation you can easily maintain the equipment without the participation of service center specialists.

Cartridge

 

In modern screwdrivers, two types of cartridges are offered: universal quick-clamping and hexagon (most often they are found in professional specialized electrical equipment, which will mainly work with fasteners). Hexagons compare favorably with the speed of replacing snap-ins, while you have to tinker with the universal chuck. In addition, the quick-clamping can work with shanks of any configuration, including hex and cylindrical. Screwdrivers that have an automatic spindle lock feature will allow you to quickly change tooling in the keyless chuck in case of power failure.

 

Gearbox

A gearbox is a device that converts high revolutions of the engine with low torque into low revolutions transmitted to the actuator of the tool (cartridge) with high torque. Most often, the equipment uses two-speed gearboxes of the planetary type, which are distinguished by relatively high performance. Its gears can be made of plastic or metal, the conclusion about the reliability of one and the other option is obvious.

Torque is regulated by a special mechanism, which has a certain number of stages. The more of them, the more accurately and efficiently it will be possible to choose the effort with which the work of the tool will be performed.

When choosing, it is important to consider that if you only plan to tighten the screws, then a speed of about 500 rev / min is sufficient and you should not overpay for unnecessary functionality. If you would like to drill comfortably, you need to stop your choice on the device from 1200-1300 revolutions / minute.

Ergonomics and convenience in work

The shape of the handle, its location (in the center of gravity of the tool), the weight of the screwdriver, the location of the control keys ... Everything should be very convenient for a particular user and made of materials that do not allow sliding even if your hand is sweating.

Models with a sufficient number of additional settings are very convenient in operation.

• Several operating speeds will allow you to more flexibly approach the task, select the correct mode and save battery power.
• The blow function allows you to work with bricks.
• Illumination can be very useful, highlighting the work surface in hard to reach places.
• The presence of the reverse (the possibility of not only tighten, but also unscrew the mount).
• Indication of battery charge.
• Good equipment (the presence of a case, a charger and an extra battery, a set of bits and heads).

Popular manufacturers and models

If you compare different models of screwdrivers for their most important characteristics, then based on the ratio of the technical capabilities of the equipment, its quality, durability, power and cost, you will get a number of brands of power tools, among which you can choose the equipment that fits optimally in all specified parameters. Below are the models that can be considered a good choice in various price categories.

Casals VZD 12 RM-2

 

If you start with budget options for home use in the price range from 2 to 3 thousand rubles, one of the examples of optimal ratios of low cost and acceptable quality is Casals VZD 12 RM-2.

 

This is a shock-free two-speed cordless tool with a keyless chuck. Its maximum torque is 9 Nm. The screwdriver has a nickel-cadmium battery with a capacity of 1.5 Ah with a voltage of 12 V. One of the main advantages of the model is the presence of a replaceable battery, reverse, spindle fixing function, drilling. The tool has a small weight (1.6 kg).

Hitachi DS12DVF3

 

This model is representative of a higher price range from 3 to 4 thousand rubles. With a relatively low cost of equipment, it belongs to the class of professional tools. Its price is explained by the use of a nickel-cadmium battery in the design. At the same time, it is quite functional, has two batteries with the possibility of their quick charge, low weight (1.7 kg), the possibility of smooth adjustment of revolutions, the presence of reverse. The maximum speed of rotation is 1200 revolutions per minute, which is a necessary minimum for performing comfortable drilling.

 

Kress AB120Set

 

This is a less well-known brand in comparison with the previous one, but it has an excellent ratio of quality and high technical characteristics. As for the price, it is in the price range from 4 to 5 thousand rubles. Among its advantages are the presence of two speeds, an additional Ni-Cd battery in the kit, 1500 revolutions / minute, high torque with the possibility of its smooth adjustment, sufficient operating voltage (12 V), weight 1.7 kg.

 

Makita BHP442RFE

 

In this case, the cost of the tool is higher than that of previous models (within 6-7 thousand), which is largely due to the presence of a replaceable lithium-ion battery with a capacity of 3 Ah and a pulsed charger. This is a high-quality professional tool with high power, long battery life, rich functionality, small dimensions. The battery fully charges in just 22 minutes.

 

Bosch GSR 10,8-2-LI

 

In the same price category is this model of the famous German brand, which needs no introduction. The screwdriver is distinguished by its ultra-compact performance, functionality, availability of a charge indicator with three LEDs, as well as all the possible functions inherent in a professional tool.Among the individual features can be noted the battery, made by a unique technology developed by the manufacturer, which allows to increase its service life by 4 times. Also in the Bosch GSR 10,8-2-LI provides battery protection from overheating, overload or deep discharge. The only problem that occurs quite often in practice is the huge number of Chinese fakes of a famous brand. On the quality in this case, we can no longer speak.

 

DeWALT DCF815S2

 

A review of popular brands would be incomplete without a representative from one of the recognized world leaders in power tool manufacturing. In this case, we are talking about the option when the high price is fully supported by the quality of manufacturing, assembly, components, excellent technical characteristics. This tool is designed for intensive continuous work, has a speed of up to 2400 revolutions / minute, equipped with a hexagonal cartridge, effective speed control, a small charge time (40 minutes) and low weight (1 kg).