How to choose a screwdriver

Many of their readers still remember the days when to work with fastening elements or threaded connections had to use only conventional screwdrivers and wrenches.Talking about the performance of these works, of course, do not even have.Very often, to «drive» the place of the screw, it was impossible to do without zasverlivaniya openings as hands effort in this case is insufficient to overcome resistance solid wood, not to mention the situationwhen required "pierce" even the thinnest metal sheet.A few hours of such work - and in the hands of the inevitable calluses, and the work progressed barely.

situation radically changed with the advent of screwdrivers .Initially, they were referred to a kind of tool, "exotic", aroused great envy.But very soon these helpful tools appeared on the open market "moved" in the category of public, and now includes a mandatory "arsenal" the vast majority of owners of houses or apartments.For those who are only now thinking about purchasing such an invaluable assistant, should be to start to understand the question, how to choose a screwdriver

, that is, on what to pay particular attention when assessing presented in a wide range of models.

main types of screwdrivers

under the general title « screwdriver "consumers often involve several types of this instrument, which still have differences with the general similarity functions.So, there are three main varieties:

• Electric screwdriver .
• Electric wrenches .
• most universal - drills .Some models can be equipped with more and shock function.

most massive demand for tools that work independently from batteries.However, it is possible to get screwdriver , powered by a conventional 220 V In / 50 Hz.Tools with a cord to connect to a power outlet and is called - "Network".

necessary to get acquainted with the basic types - so it will be easier to make a choice, really representing the alleged nature of the works, their intensity and the load on the tool.

electric screwdriver.

Although on its main operational performance and overall functionality rechargeable screwdriver in some way inferior to the standard Drills , they have their own specific virtues that make these tools are widely popular amongprofessional artists and amateurs.These invaluable "pluses» can include low weight, compact arrangement of the device, high levels of ergonomics.This allows the use of rechargeable screwdriver under, when the use of a larger instrument or involves great inconvenience, or even impossible.

Such tools nt Article ANOVA indispensable in production lines for the assembly of small household equipment, computer and office equipment, is widely used to them masters in the production process or the final assembly of the furniture.The compact, ergonomic and light weight are the screwdriver does not cause rapid fatigue of hands, and so it is very convenient for work at height, including, for example, when the installation of suspended ceilings.

cordless screwdrivers are different in layout.Many models have a cylindrical body, which, however, equipped with swivel, allowing to emerge, for the concentration of efforts clamping arms if necessary.

Other screwdrivers have the usual "pistol" shape, but always - a very compact, comfortable bed in the palm.

Also, available are very comfortable in the model, in which the articulation is provided for the working head with a rotating chuck.This opens up the possibility of tightening the mounting or removal in the most inconvenient places where it is impossible to have a common tool.

compactness of power tools is achieved through the use of small batteries with a voltage typically in the range of 3 to 9 B. Screwdriver not denounced high speeds - as a rule, from 150 to 250 rev. / min.For their direct purpose it is enough, as the tightening torque of about 10 N × m.For the vast majority fastening elements, especially in the domestic environment, these indicators abundantly enough.However, there are also more committed model, equipped two-speed switch, and allow to carry out drilling works with plastic and wood - the frequency of rotation they can reach up to 600 rev / min..

Almost all rechargeable screwdriver equipped with cartridge adapter for hexagonal bits with shank ¼ inch.Usually the bits to the various types of fasteners, as well as drill small diameter with the same hex shank included most screwdriver .

Unlike larger tools, electric screwdriver often equipped nonremovable battery, placed in the product housing.To charge using a special block power adapter , plugs into a power outlet.

What is the result?If the owner in his toolbox is a good drill, and it is only necessary to mechanize the process of working with fastening elements, the rechargeable screwdriver can be a very useful aid.The convenience of this operation it is superior screwdriver , but much inferior to his features.

Electric wrenches

More one type of tool that very similar to screwdriver , and even in certain circumstances can be applied in the quality, but it also has features that are directly related to itsdirect destination.

If the master on the specifics of his work have to often resort to the installation or dismantling of carving connections medium or large diameter, it is restricted to perform repetitive operations using wrenches- it means to dramatically reduce their productivity.A classic example - put to the flow assembly line, or that is closer to private practice, vehicle repair or tire mounting workshops.In addition, in particular, for the repair of cars, very often deal with the old, "soured" nodes manually unscrew that, even after treatment with a special composition, it is very difficult.

Exit - use impact wrench .Its design is such that in addition to the usual rotary motion to the working part of the special mechanism of the spindle is transmitted and pulsed exposure to a certain frequency.In short, it is a kind of « mikroudary », able to budge, and loosen even the most rusted nuts or bolts, without violating the integrity of the faces of their heads.

Most wrenches have the usual "pistol" scheme, but may additionally be equipped with a removable side handle for the concentration of downforce at breakaway connection. Nevertheless , there is a "direct" cell phones, perpendicular to the working head - for operations in confined spaces.

Of course, for such operations require special power drive - usually it ranges from 350 watts for most small tools and even up to 1300 watts for professional-grade devices. rotation speed is not critical, and it is usually small.But through this is achieved by a high torque that even "feeble" shock wrenches is about 200 ÷ 300 N × m (compare, for example, with already considered rechargeable screwdriver!), But in the professional class modelswith electric power up to 1000 watts, this figure can even reach 1000 N × m.

In view wrenches very similar to screwdrivers , but they are distinguished feature - the absence of ring adjustment of maximum torque ( "ratchet").Differs and working spindle tip - often there is an adapter-square socket heads.Dimensions of the square from different power models may vary - ½ (more often - at the domestic end models), or even ¾ of 1 inch (a professional powerful tool), and then , and sets the appropriate bits must be purchased.Although, in this case there are special adapters.

Some manufacturers just provide increased versatility adapter.Thus, in the spindle-center of the square can be the nest for the insertion of standard hexagon ¼ inch - shank drill bits or .

But even that does not add too much wrenches versatility.His specific electromechanical characteristics still "incarcerated" under the specific operations.High torque, but still and pulse mode, can be completely unnecessary and even harmful when working with materials that do not require excessive force.A low rotation speed may be insufficient to carry out drilling operations.

In short, the impact wrench , if the specifics of the work Matera suggests its frequent use, will be a good addition to screwdrivers, but to completely replace it in the householder's arsenal is unlikely to.

In fact, many well-known manufacturers produce tool sets, in that enter and drill , and stroke wrench , that workfrom one set of batteries.Here it - really versatile set .However, the cost of it - is quite high, and such a purchase should really be justified.

Drills

This - the most widespread and most commonly acquired by a variety of similar tools having improved versatility.

The vast majority of these screwdrivers performed on the base "pistol" scheme.

1 - housing impact-resistant plastic (some professional-grade models have a metal housing).Inside is the drive with the controls, sound air cooling system.

2 - pistol grip.The high-quality models has rubberized covers that prevent slippage of the tool in the hand of the worker, make the tool as easy as possible.

3 - battery with a locking mechanism in the handle.In most of the models is a view similar to that shown in Fig.However, some modern screwdrivers equipped with powerful batteries compact type, which are completely hidden inside the handle, making the work with the tool even more comfortable.

4 - button (the trigger) start.Moving the trigger at the same time continuously adjusts the spindle speed screwdriver .Typically, the trigger is also covered with a lining of rubber or soft plastic.

5 - the switch of spindle direction (reverse).Made so that the switching process is as simple as possible - enough finger efforts.

6 - switch gear, allowing the tool to change operating modes - low speed with a large tightening force, or, conversely, high-speed rotation required to perform drilling operations.This feature is not available in all models.

7 - chuck operating tool clamping - bit holder or drills .The design of the cartridge may vary.Some models are not equipped with chuck - they provided hexagon socket ¼ inch shank bits for standard or special drills .About varieties of cartridges will be described below.

8 - jaws chuck.

9 - an indispensable element of any screwdriver - torque limiting mechanism to be transferred to the cartridge.Usually performed on a "ratchet» - when exceeding the set torque clutch slippage occurs with a characteristic sound.Number of installation positions can be different - from 5 ÷ 6 in low-cost models to the two dozen or more professional tools.Be sure to provide the drilling mode - when rotation is transmitted from the gearbox to the cartridge without limitation the moment.This mode is indicated by an icon.

10 - modern models screwdriver in in ce often equipped with an LED backlight system workspace. LED Location may vary.

Thus, this type of screwdriver is the most versatile, and that determines its widest popularity among professionals and home craftsmen.

What to look for when choosing screwdriver

deciding to purchase a particular model Drills , the future owner of the tool must clearly submit to any purposes heneeds, any operations planned them to perform and a intensity exploit.These preliminary « basting » will be the basic points when evaluating the performance of the proposed sale devices.

type of batteries and their characteristics

Post consideration is advisable with "energy» screwdriver .Whatever wonderful tool itself, its performance depends on the battery, the cost of which, incidentally, is always more than half the price of the entire set.