A screwdriver is an indispensable tool for any experienced craftsman. Therefore, his choice must be approached very carefully. In today's market there are many different types of electric screwdrivers that are designed for different jobs.
Screwdriver circuit.
To choose the right screwdriver for yourself, decide what your job will be. This is necessary so that later it did not happen that the instrument was bought for a lot of money, used and now lies and is no longer needed on the farm.
To choose the right professional screwdriver yourself, you need to focus on several key parameters. It is power, speed and torque, the characteristic of the cartridge, reverse and additional functions. Consider all this in more detail.
The main indicator of the health of the instrument is the power source. As a rule, before the screwdrivers were taken to be divided into battery-type devices and working exclusively from the network. But now all electric screwdrivers have a battery of a certain type. Therefore, it does not make sense to divide the instrument into power sources.
Types of nozzles for the screwdriver.
First you need to check the plug. The most good - collapsible. Their advantage is that if they break, they can be untwisted and repaired. In the event of a malfunction, a solid-molded plug will require complete replacement along with the cord.
The second important characteristic of the power source is the type of battery. Even a cordless screwdriver uses battery power. In total, there are now three types of batteries that differ in power and environmental safety.
So, the lithium-ion type of battery is considered the most powerful for a screwdriver. Because of this, it has a rather high cost. Such batteries are well tolerated recharge and long able to hold a charge. The main feature is the lack of memory. Even with an incomplete fit, the battery can be recharged without problems. In this case, the capacity will not decrease.
However, there are some minuses here. For example, batteries of this type do not tolerate sudden changes in temperature. And the cold is unfavorable. Therefore, to use such a screwdriver in conditions of constant cold is undesirable. And the effect of self-charging in batteries is rather weak.
The second type of battery is nickel. They come with the addition of either metal hydrides or cadmium. Among themselves there are practically no differences. But from lithium-ion type batteries differ greatly. These batteries have lower power, have a memory effect, which causes the instrument to fully discharge before the next charge.
Screwdriver chuck circuit.
It should be noted that these batteries are very dangerous in environmental terms, because they contain highly toxic elements. Therefore, to use a screwdriver with a battery of this type in everyday life must be extremely careful. For the same reason, do not dispose of self-damaged batteries or screwdrivers of this type.
But they also have pluses - it is resistance to temperature changes, keeping even the most severe frost without damaging the instrument characteristics, as well as low price. Due to the cost of screwdrivers with such batteries, it enters the market much more than with lithium-ion batteries.
The next characteristic is the type of cartridge. As a rule, either key or keyless chucks are assumed for screwdrivers. Keyless chuck allows you to clamp the drill pretty quickly without using a special key. This is good in order to save time, but badly on the other hand, since there is a greater likelihood of drill failure. The cartridge can be with one fastening clutch or two. Of course, it is better to buy dvuhmuftovy cartridge.
Keyed chucks are the mechanism where the drill is fixed by turning a special key. As a result, you can even feel the clamping density by touch. Therefore, the reliability of fastening increases several times.
So, we can conclude that it is best to choose a cartridge with a key if you intend to use a screwdriver all the time and you are not in a hurry to change the drill. Keyless chucks are justified when you need to change the drill many times in a row. At the same time, the work performed by the tool is not particularly difficult.
Table of the main characteristics of screwdrivers.
The most important indicator is the maximum speed of rotation of the working nozzle. Depending on the speed, you can tighten or twist the screws in a certain period of time.Accordingly, the higher the speed, the faster the work will be, and vice versa.
It is important to know what the screwdriver will be used for. If it is exclusively work with screws, then 500 revolutions per minute will be enough. But if something is also planned to be drilled, then the average speed should not be lower than 1000 rpm.
Modern screwdrivers are equipped with special nozzles-regulators, with the help of which you can independently adjust the speed of rotation. Therefore, it is important to have such a regulator. After all, even during normal work with screws, it will be more convenient for some people to work at low speed and for others at high speed.
Maximum torque is another important indicator. It determines the force of action of the rotational element on the body on which the work is performed. This is already a more serious indicator, since the opportunity to work with screws of certain sizes will depend on this point.
Three-jaw chuck device.
As a rule, professional screwdrivers have a torque of about 10 N / m. But household tools can have a moment of about 15-30 N / m. That is, in the first case, you will be able to work freely even with the largest and most massive screws, and in the second case, the maximum will be enough for standard screws of medium size.
It is very important that the screwdriver has another regulator that will determine the force of the torque. From this will depend not only the optimality of work with a certain size of fasteners, but also the ease of twisting into materials of different hardness. Again, to work with solid foundations need to choose more torque.
Another important part of the screwdriver is the reverse. They call the possibility of rotation of the main cartridge in the opposite direction. Of course, this feature must be integral to any type of screwdriver. But despite this, not all tools have such a property, which is important to pay attention to when choosing.
A good electric screwdriver is not only equipped with a reverse function - it also has a special switch that allows you to block the switch button in the opposite direction. And this is very important, since during operation the button can be accidentally wounded, as a result of which both the screw, and the drill, and the base can be damaged.
And it remains to make a brief overview of some additional functions. These include the backlight, the spindle lock (this has already been discussed above, has more to do with the reverse), and the external characteristics of the tool. As a rule, the reverse function is sometimes also referred to as additional.
As for the backlight, some high-quality screwdrivers are equipped with a small but powerful enough flashlight with which you can work even in the dark. This is an important function for professionals whose work is associated with the constant use of the screwdriver in the most unusual conditions.
As far as external characteristics are concerned, screwdrivers have a different handle shape. So, there are tools designed to work only when they are held in a horizontal or vertical position. This does not mean that it is impossible to work in another position. Just do it is not so convenient. And there are screwdrivers, which are always convenient to work with. As a rule, they have an adjustable knob.
So, the main points that need to be considered for choosing a screwdriver for different jobs are fully considered.
Accounting for all the above characteristics will tell you how to choose the best tool, without spending more than necessary money.