To date, the market you can find a large selection of screwdrivers. They, like any other building tools, are characterized by functionality, shape and other parameters. Next, we will tell about how to choose the right building tool correctly, given all the characteristics and features of the available models in the market.
Content
Basic moments
Screwdrivers are divided into household and professional. It depends on many characteristics of the device, for example, from the size of the cartridge, the nutrient element, power, configuration and prices.
Given the varieties of the existing nutrient element, distinguish:
- rechargeable aggregates
- screwdrivers operating from the network.
The main advantage of the first is their autonomy, i.e. You can work with them, anywhere. If only there was a battery charge. The second type of tools is "tied" to the electrical outlet. Although, if you purchase an extension, then it is possible to work with them as far from the outlet, as far as the extension is enough, but wearing multi-meter wires - dubious pleasure.
It is no secret that far from all construction work is carried out not far from food sources. Therefore, in the field conditions, the aggregates operating from batteries are undoubtedly more convenient. Such models are in great demand. Therefore, we consider the types of batteries a little more. But to begin with, briefly list the main elements of the screwdriver:
- So, in any similar tool there is an electric motor and a gearbox, with which the force is transmitted to the spindle.
- The spindle contains clamping cartridges.
- A clutch that allows you to adjust the torque is attached to the gearbox.
- For attaching nozzles on the motor shaft, a clamping cartridge is used.
- To start the device in the electronic tool system, a button is provided.
- In addition, it is often a tool equipped with a switch to the reverse.
Selection of batteries
The choice of batteries today is quite extensive. In modern units, lithium-ion (Li-Ion) devices are increasingly used. They withstand three thousand cycles "charge-discharge." They weigh a little, quickly charge and practically do not have the effect of memory. In addition, they have a high specific capacity and minimum charging time. The disadvantages of these batteries should be attributed primarily - it is only three years. In addition, for maximum return, it is required to be constantly used in operation. And such batteries have a fairly high price. Also in some old models there is a significant disadvantage, due to which the battery does not work out when it is completely discharged. In most modern devices of this type, such a drawback is eliminated by embedding the control element that does not allow the battery to be completely discharged.
There are aggregates equipped with nickel-cadmium (NI-CD) batteries. These batteries are actively used for quite a long time. They withstand 1.2 thousand cycles of "charge-discharges", which is quite small. They can serve until five years. At the same time, they are able to operate at low temperatures. Moreover, it is the cheapest batteries. In short, then their advantages should be attributed to the fact that they are capable of stored in a fully discharged state. In addition, such devices are resistant to low temperatures, have a relatively low price and without problems can be restored after long-term storage. As for the shortcomings, they should be attributed to a small container. In addition, such devices have a high self-discharge, i.e. If you charge it and after that, at least 5-7 days they do not use it, then it is most likely to completely discharge. In addition, it has the so-called memory effect, because of which it can be charged only after it is completely discharged.
Something among the two listed types of batteries is nickel-metal-hydride (NI-MH) devices. And in the screwdrivers they are established infrequently. They are designed for about a thousand cycles of "discharge charges". It should be noted that they practically do not have the effect of memory, i.e. They can be charged, even if they are not completely discharged. Such devices are good for the fact that they have a minimal self-discharge. They also have small dimensions and high specific capacity. Of the disadvantages, first of all, it is necessary to note the weight of these batteries. In addition, they cost more than NICD devices, and "lifetime" only 700-1000 charging / discharge cycles. At the same time, in a fully charged form, they will not be able to store them. It is also worth noting their sensitivity to low temperatures.
As it should have been clear, the batteries differ not only with a capacity, but also with tension. From the tank directly depends on the battery life of the tool, i.e. How much he can work without recharging. As for the voltage, it affects the value of the soft and hard torque indicators. In other words, the larger tension requires the tool, the more powerful.
Regardless of what the screwdriver works, - from the network or battery, it is always outwardly similar to the usual drill. The differences between them are actually a little. The main difference is the possibility of adjusting the torque in the screwdrites. In any case, those and other tools are household and professional.
The common advantages of network models can be attributed to the fact that these screwdrivers do not require charging. At the same time, the need to connect a tool to the power grid is a minus, because Limits mobility.
Power of aggregate
Consider now which choose a screwdriver, given the existing power of the device. Depending on the mode, the power of the screwdriver is characterized by such options as hard and soft torque. The hard torque reflects what force is applied in drilling mode. In general, the frequency of rotation from different models, of course, is different. On average, this value is 1 thousand rpm. But there are aggregates and with a large value of rotational speed. The maximum possible force of the tool is reflected by a soft torque. It is needed to execute the "unscrewing and twisting" function. Most models can be changed from 0 to 350 rpm. Both listed parameters are measured in Newtonometers. These characteristics directly affect the tool power. In addition, they affect the practicality of the screwdriver.
For example, a torque screwdriver from 25 to 30 nm makes it easily tightening to 7 cm long in the wood. These units can spin self-tapping screws up to 10 cm. If even longer self-tapping screws are required, then before screwing them will need to pre-make holes.
How to choose a screwdriver: equipment equipment
If you wondered what firm to choose a screwdriver, then look at the initially configuration of the device. Usually included, in addition to the tool itself, there is a plastic caides for carrying, a pair of batteries, a charger, at least one bits and instructions. Often the completeness can be supplemented with lanterns and battles. Sometimes the presence of some specific accessories can become decisive when choosing a tool.
As for the cartridges, most of the models they are fast-on. For the spindle, forced braking is usually used, i.e. When the juro is released, the rotation of the unit stops instantly. Do not buy a screwdriver if such a braking system is not provided in it. In expensive models there is a so-called pulse mode. When the tool goes into this mode, then the tapping occurs with dimensional jerks, which makes the drilling process easier, because The drill is no longer so "goes" to the side. This function is usually found in professional tools for mostly. Most often, the builders prefer the Makita screwdrivers.
Varieties of cartridges
Total types of cartridges are two - it is a quick and key. The first is used for drills and bit-holders. Its work is ensured by a quick-release mechanism. The key, as it should be clear from the name, is controlled by a gear key. Such a cartridge can have one or two couplings. If the clutch is one, then the tool usually provides a mechanism that allows you to block the shaft, which may be required when changing nozzles. If there are two couplings, the locking mechanism is usually not. Instead, the cartridge holds thanks to one of the couplings.
What is better to choose a screwdriver: sizes
The size and ergonomics are not particularly important for the screwdriver, but still it is worth considering, especially if a lot of hours have to work with the tool. It is impossible to say with confidence that the unit size is better. On the one hand, a small tool is preferred, because He is less weighs and his hand is not tired of it. In addition, it is convenient if you need to get to hard-to-reach places. But self-sufficiency will be complied with such a tool. Heavy and massive aggregates, as practice shows, are more suitable for this task. Nevertheless, more people still prefer compact devices. Still comfortable work with the tool is preferable. But if you have to work with a tree, then it is better to use heavy and powerful aggregates.
As for ergonomics, before purchasing the tool, you need to make sure that it will be good to sit in his hand. Just take it in your hand, be sure to pay attention to the handle. Many models have a steep angle between the handle and the barrel. This is a pretty important point, since with a multi-hour operation, a strong corn is formed between large and index fingers. Therefore, it is better to take devices that have almost straight corner. Most models have a speed switch located on top. In addition, uncomfortable buttons are installed on some models to switch the direction of rotations.
Other features
Reverse or "Return" is a fairly useful feature. For example, with the help of it, you can unscrew the tight screw or pull the drill stuck in the solid material. For this mechanism, the electronic switching of the electric motor poles is usually used. To be more convenient, the switch to the opposite is usually placed next to the start button. He has two positions. At the same time, in the middle position, the tool is blocked, which is useful in order to prevent the accidental start of rotations.
