Screwing and unscrewing the fasteners is done with a screwdriver. You must first decide what to buy a screwdriver.
Cordless screwdrivers are easy to use, as the wire does not interfere with getting to the most inaccessible places.
Masters use equipment with a good battery capacity, high-power, fully equipped with a large number of options. To choose the right screwdriver, you need to consider its technical characteristics.
Experts advise when choosing a screwdriver to determine which surfaces to work with. Solid materials require apparatus with a rotational speed of 1200 rpm. In household appliances, this figure should be equal to 400 rpm. Torque in professional units reaches 130 Nm, and in household - no more than 15-20 Nm. Operating voltage in household and professional models is different. In the first case, it reaches 6 V, and in the second - more than 12 V.
Device cordless screwdriver.
Screwdriver can work on the network or on battery. With the help of the last device the master can work as a tool in rooms without electricity. In terms of power, the equipment, which operates from the mains and from the battery, is almost the same.
The disadvantages of devices that are powered by a battery include:
- the need to purchase a new battery after a certain period of time;
- high cost;
- limited work time;
- the need to keep the unit on weight in the process.
Experts identify several types of batteries in rechargeable devices: NiMH, NiCd and Li-Ion. They must be assessed according to criteria such as:
- charge holding time;
- energy intensity;
- low weight;
- fast charge;
- no memory effect.
Li-Ion batteries have a short life. Transformer and impulse chargers that carry a constant or pulsed current are on the market. Transformer-type devices are heavier, while pulsed devices are equipped with electronics, allowing the battery to be adjusted during charging.
Battery charger charging device.
The reliability of the instrument under consideration depends on the features of its design, the quality of the parts used and the assembly. The main parts of the screwdriver - gearbox, engine and cartridge. Gearbox allows you to convert high engine speed. Most of the tools are equipped with planetary type gearboxes with 2 speeds, which have high performance. Material for gears - metal or plastic. A special mechanism with several steps adjusts the torque. From the number of stages depends on the efficiency and accuracy of the selection of the force with which the unit will work.
Screwing screws allows speed of 500 rpm, so there is no need to purchase professional equipment for solving household tasks. Quickly drill allows the tool with a speed of 1200-1300 rpm. In screwdrivers installed contactless or collector motors. Contactless units have a large technical resource, operate smoothly, do not require maintenance, work quietly and have significant dimensions.
Collector motors can be serviced independently. The devices use cartridges of one of 2 types, with 6 edges and universal quick-clamping. The first option is used for the production of professional equipment and has a high replacement rate of snap-ins. Fast-tightening cartridges can be used for work with shanks of any configurations (cylindrical and with 6 sides). Tools with an automatic spindle lock allow you to quickly change the snap in the universal cartridge in the absence of power.Back to table of contents
Main types of devices
The greater the power of the screwdriver, the more massive and heavier it will be.
The handle and control buttons of the screwdriver should be made of materials that do not allow the hand to slip, if it sweats. The weight of the device, the shape and position of the handle of the buttons should be convenient for the master. Additional settings help make the tool convenient for the wizard:
- blow function, allowing to work with brick surfaces;
- availability of several working speeds;
- reverse function, which allows you to unscrew fasteners, if necessary;
- full set;
- battery charge indicator.
Knowledge of the most well-known manufacturers, models and their features allows you to choose a screwdriver that meets the necessary requirements.
Casals VZD 12 RM-2 - one of the budget models, suitable for working in living conditions. The unit has 2 speeds, without a blow function, it works from a NiCd battery with a voltage of 12 V and a capacity of 1.5 A / h. The device uses a fast-closing universal chuck. Torque reaches 9 Nm. The tool performs the function of reverse, drilling and fixing the spindle. Included is a replaceable battery.
Hitachi DS12DVF3 is a budget model of professional equipment with a NiCd battery. The weight of the device is 1.7 kg, there is a function of reverse and smooth regulation of revolutions. The rotation speed reaches 1200 rpm. Includes 2 batteries.
Kress AB120Set combines high specifications and quality. The rotation speed reaches 1500 rpm, there are 2 speeds, the function of smooth regulation of large torque, the operating voltage of 12 V. Included is a replaceable NiCd battery. Makita BHP442RFE - model of high-power, professional tool. The device has high functionality, small dimensions and is able to work independently for a long time. The battery fully charges in 22 minutes.
Bosch GSR 10,8-2-LI is a functional and compact screwdriver. The battery is manufactured using a unique technology and has a long service life. The battery is protected from overload, overheating and deep discharge. DeWALT DCF815S2 allows you to perform intensive work for a long time. Rotational speed - 2400 rpm, speed control, hexagonal cartridge, weight - 1 kg, it charges in 40 minutes.