Every man who does something at home usually has a screwdriver. Well, or its acquisition is planned. After all, without this tool can not do neither during repair, nor during construction, nor during small work on the house. Collect furniture, hang a cornice or shelf, unscrew old screws - in all these cases, this device will help out. Today we will talk about how to choose a screwdriver that most fully meets your ideas. At the same time, we determine where the "golden mean" is in a combination of price and quality.
- 1 Where screwdrivers are used and how they are arranged
- 2 How not to be mistaken when choosing a screwdriver
- 3 Video: We choose a drill-screw driver
Where screwdrivers are used and how they are arranged
This tool is actively used by the owners of cottages, and those who live in their own apartment. Whatever works on construction or repair are made, without a screwdriver can not do in any way. This will tell any home master who has got used to rely on his strength and ability. And professional builders also certainly have a screwdriver in their arsenal. It is convenient for them to fix gipsokartonnye sheets during finishing works. And only furniture without this tool is completely impossible to assemble.
Consider the elements that make up the screwdriver:
- Electric motor rotating at a certain speed.
- The planetary-type reducer transfers the force to the spindle, which is equipped with a clamping chuck.
- A coupling is connected to the reducer, which regulates the torque.
- To attach to the motor shaft nozzles, called bits, there is a clamping chuck.
- The electronic control system is equipped with a button to start the device, as well as a backstop switch.
- The battery is usually used as a power source. Therefore, this type of instrument is convenient to use where there are no electrical outlets, as well as in places where the cord will not reach.
Screwdriver in disassembled form.
And now we list, for what works it is expedient to use a screwdriver:
- Screwing and unscrewing a wide variety of fasteners. These are self-tapping screws, bolts, screws, and, of course, screws.
- When installing this unit, you can tighten the dowels and anchors firmly.
- The tree, both soft and hard, is perfectly drilled with a screwdriver.
- They can also drill a metal surface.
- This device is quite possible to cut the thread in metal (and not only) details.
How not to be mistaken when choosing a screwdriver
Keep in mind that when you go to the store, do not pay attention only to the cost of the device. When deciding which screwdriver to choose, carefully read the passports of the models you like. They will necessarily indicate the most important technical characteristics of the device. These are: the rotation speed, the type of battery (if, of course, it is available) and the torque. On these parameters, and you must choose your tool.
For "pro" or household screwdriver
Think about what kind of repair and construction work you plan to do. Proceed from this, and make your choice. If you are not so keen on making, and you will only need to get the device out of the case a couple of times a month, there's no point in taking a professional screwdriver. The truth is, there is no need for a candlelight - an amateur battery-powered model, that's enough for you. All the necessary functions are available, but it weighs much less than the professional one.
If almost every day you need something to assemble, fasten or build, then look aside not very cheap, but very powerful professional models. They, as a rule, work from a network, have impressive dimensions and weight. It makes sense to choose such network screwdrivers for those who have an untold edge of work with heavy loads ahead.
About the torque and speed of rotation
The torque determines what force the screwdriver applies to the screw to be screwed, or with what force it resists the load. In household appliances are used, the torque of which is from 10 to 15 Newton-meters. Professional models can have a torque of up to 130 Newton meters, which makes them able to drill very hard materials. The motor shaft of such devices makes 1200-1300 revolutions per minute. Household models are satisfied with 400-500 rpm.
Depending on the torque, the length of the screw to be screwed, as well as its diameter, is selected. More powerful screwdrivers can tighten more thick and long screws. Also, these devices can be used when working with sufficiently hard materials, without fear of breakage.
From other power tools, the screwdriver is characterized in that its torque can be adjusted. To do this, use a simple device - a limiter. It is a ring located immediately after the chuck. With the help of it you can set a certain effort after which the screw will not screw more. They screwed in the screw - the cartridge immediately stopped, although the engine is still spinning. At the same time, the sound of the rattle is clearly heard. Such a limiter protects the instrument from many troubles: bit wear, slit splitting in the samorez, as well as its too deep inundation into the surface.
Maximum torque limiter.
The ratchet at the motor clutch protects it against overloads, allowing the rotating shaft to freely slip. The set maximum torque, by the way, is enough to make the screw tightest, and the engine does not overload. To go into the drilling mode, you need to move the clutch to the opposite extreme position. In this case, the torque limitation will be removed, ie, the screwdriver will work as a conventional drill.
Usually screwdrivers have two operating modes - one allows drilling, the other one - to turn the screws.
To correctly choose a screwdriver, consider and some more nuances. It is necessary to check whether the electric motor is stable running under load, whether its rotation frequency is maintained. It is important and the quality of the power unit, its ability to hold a charge, as well as the power of the device with a worn out battery.
Rechargeable or working from the network?
There are two types of screwdrivers: powered by a power cord and having their own battery. As for the first, they have a solid weight, and you can work with them only close to electrical outlets. However, you can also buy an extension cord, depending on its distance and the range of use of the tool will depend. Accumulator devices are easier, and also have a significant advantage - autonomy.
To build it is not always necessary near the outlets, that is why in the field conditions the models with their own battery are, of course, more convenient. Agree, a little pleasure - to carry a meter of wire, which, as luck would have it, is also confused constantly. And when working at altitude and does not get to use network models. After all, they are also heavy - raising them is problematic. Therefore, let's consider more models with a battery. It is important to choose the correct type here.
The most widely used battery screwdriver.
Network, more professional model.
Choose a battery with the mind
To work with comfort, rather than running the instrument every half hour, carefully pay attention to its battery. In how to choose a cordless screwdriver, there is no special difficulty - simply take the device more powerful. And an excellent service will be provided by a spare battery if it is included. As for the time of recharging, the professional instrument is about an hour, and for amateur - up to 7 hours. It depends on the charger.
In screwdrivers, three types of batteries are used:
- nickel-metal hydride.
1. The latter are becoming more popular, and today many new European models of screwdrivers are equipped with environmentally friendly Ni-MH batteries. Small and light, with no memory effect, these batteries have only two drawbacks. They do not like frost and overcurrent. Yes, the price is still a little too high. But the number of recharges with a stable capacity is 1500 times. For storage, you need to charge these batteries well, and stored in a discharged form is not permissible. But they do not have as much memory effect as nickel-cadmium and are more powerful.
2. Batteries based on nickel-cadmium elements are more toxic, but the amount of recharge is twice as high as in the previous type. Therefore, the tool sold today in stores and markets, mostly has Ni-Cd batteries. They are also quite cheap, but they are not afraid of frost at all. So for the Russian conditions, there is nowhere better to go. That's just these batteries suffer a strong self-discharge, and even the effect of memory - this is a significant disadvantages. For storage, do not forget to discharge them completely. Otherwise, you risk getting a battery with a smaller capacity.
3. Lithium-ion batteries in screwdrivers are built-in not so often. They are even more sensitive to cold than nickel-metal hydride batteries, and their power is low. The number of recharging is up to 3000, there is no memory effect. The large capacity of the battery is poorly compensated by the prohibitive price. Self-discharge, they are practically not affected. They are somewhat more convenient when used at home, but the price is not encouraging.
To choose a good screwdriver, do not spare the time to choose its battery. After all, the battery costs more than half the price of the instrument, more precisely, from 60 to 70 percent. Read the instrument's passport and compare the following parameters:
- Battery voltage;
- capacity of the battery;
- presence or absence of memory effect;
- presence or absence of self-discharge;
The battery is a removable element. It consists of several power supplies in a common housing. They are fastened together with the help of plates. The total voltage is summed at the output, making 24, 18, 14.4, 12 or 10 volts. It determines the duration of continuous operation and the power of the device.
Capacity depends on what element is installed inside the battery. It determines the total number of recharges and battery life. Over time, the capacity is reduced.
The effect of memory on a charge is the ability to lose capacity if the battery has not been discharged, and then charged completely. That is, before charging it must be completely discharged. Lying around in the case, the charged battery will still lose its charge. Therefore, it is also necessary to completely discharge the nickel-cadmium battery if the device is to be sent for storage.
And one more tip about the battery: look not only at the output voltage, but also at the ratio of the current to the running time. This value is measured in amperes per hour. The higher its value, the longer the battery will hold the charge. Batteries with the same voltage may have different amperes / hour.
Varieties of cartridges
There are cartridges for clamping parts of two types: quick-clamping and key. To clamp the latter you need a special dowel-type key. If a quick-clamping mechanism is used, everything is much simpler - you can also insert a drill into it without difficulty, and a bit holder.
In turn, a cartridge controlled by a key can have either one or two couplings. If one coupling is used, the device additionally has a mechanism for blocking the shaft when replacing one nozzle with another one. If the coupling is two, then instead of locking the cartridge holds one of the couplings. The second clamps the cartridge.
Presence of a return course
The reverse move, commonly called the reverse, will help to unscrew the screw, and pull the hopelessly stuck drill out of the hard material. As a rule, for this purpose, electronic switching of the poles of the electric motor is used. For convenience, the switch to reverse mode is located next to the device's start button. It has two positions, and in the position intermediate between them, the device is blocked. This is necessary to not accidentally press the button at the wrong time.
Reverse switching function.
Convenience and design
Reflecting on how to choose a screwdriver for your home, do not limit yourself to viewing pictures on websites. After all, you use the tool - and then hold it in your hands, checking to see if it has tight buttons, if they switch well. The center of gravity should be in the handle - so the hand will grow tired less. After the cartridge, there must be a ring for adjusting the twisting force. When the screw is screwed to the end, this device will not let it go too deep. And the tooling will not wear out quickly.
A small and low-power screwdriver is useful when assembling furniture.
A classical model containing all the basic functions.
Screwdriver with automatic feeding of self-tapping screws, is a whole combine that is useful to professionals.
Screwdriver with magnetic holder for self-tapping screws.
Function of illumination at work.
Battery charge indicator.
What lies in the case
Screwdriver accessories can be different. Better, if it includes not only the device, but all the necessary attachments. This will in the future save both money and time. After all, screws, bolts and screws are produced today with many variants of hats - that's why the nozzles will need various ones.
Having learned in this article all the possible parameters, write yourself the best ones that are right for your needs and go to the raid on the shops to make your choice.
For a home appliance, this can be the following parameters:
- Torque: from 10 Newton meters.
- 400 - 500 revolutions per minute.
- 2 operating modes (twisting and drilling).
- Presence of the reverse function.
- Device type: battery.
- Battery type: nickel-cadmium or nickel-metal hydride.
- Voltage: 10 - 14.4 V.
- Meaning: ampere / hour the more the better, if the two batteries have the same voltage, and this indicator is higher, then it is better to give preference to this particular device.