How to choose a cordless electric screwdriver expert advice
This type of tool has become more widespread. These devices are powered by batteries, the capacity and charging time of which can vary significantly.
- independence from the availability of electricity and the location of the outlet, which gives freedom of action. Work can be performed at a height, in hard-to-reach places, but practically in the field, and the wires will not get tangled underfoot;
- the scope of application is wider, which follows from the autonomy and mobility of the tool.
- dependence on the battery charge level, the need to constantly monitor this parameter and periodically charge the batteries. Experts recommend taking a spare battery with a cordless electric screwdriver: while one is charging, the second is working. It is preferable to choose batteries that charge quickly;
- in terms of power, the cordless tool loses to the mains one. The torque may not be enough for working with hard materials, but there are exceptions here. professional cordless screwdrivers are quite powerful and reliable.
Professionals know that choosing a cordless electric screwdriver is even more difficult than a network one, because it is necessary to take into account not only the functions of the device directly, but also the features of the battery.
The first thing to look out for is the type of battery:
- lithium-ion batteries, Li-Ion. This is the most popular and modern type of battery, it is used everywhere, not only in screwdrivers. Among the advantages are low weight, sufficient power, no memory effect, long service life of charge / discharge cycles (about 3000 and more), high charging speed. Of the minuses, the relatively high cost, so this is a good option for permanent, but not one-time work. This battery is not designed to work in cold weather. In order for the battery to last as long as possible, it is better not to discharge it less than 15% and not to charge it more than 90%. Service life is about 3 years;
- nickel-cadmium, Ni-Cd. They are highly resistant to low temperatures and power surges. On the other hand, they have a pronounced memory effect, so it is better to discharge such a battery completely and fully charge it so as not to reduce its capacity. The battery can withstand about 1000-1500 charge / discharge cycles, but it takes a long time to charge. about 7 hours, so it is better to have a spare battery. The battery’s weight is significant, but it is the cheapest. Service life is about 5 years;
- nickel metal hydride, Ni-MH. Such batteries are becoming more and more popular, they are light in weight, low resistance to low temperatures, and the memory effect is not expressed. A big plus is the minimum self-discharge, and a minus is the price;
- Lithium polymer batteries, Li-Pol, are rarely used in screwdrivers. These are capacious, but not very durable batteries.
In addition, it is worth paying attention to the battery capacity in Ah: the higher it is, the longer the electric screwdriver can work without recharging. Another important parameter is voltage in Volts. The maximum power that can be obtained from a cordless electric screwdriver directly depends on this indicator.
Typically, the voltage ranges from 9 to 36 V. For simple work, you can take the 9 V model: these are compact tools for rare use. a 12 V electric screwdriver is an excellent option for a household tool, suitable for many home repair work. an electric screwdriver 14 V is the golden mean, screwdrivers for 18 V and more are already a tool for professionals.
Electric screwdriver chuck type
In screwdrivers, there are mainly two types of cartridges used:
How To Choose A Cordless Drill or Impact Driver. Ace Hardware
To decide which electric screwdriver to choose, you need to remember the previously defined purposes for using the tool.
Screwdrivers with a keyless chuck are more versatile and allow you to install both bits and drills, and even a mixer attachment and a grinding brush. Changing the attachments is quite simple and quick, fixation occurs due to the rotation of the clamping ring. The mechanism can be two-sleeve, when two rings have to be turned simultaneously, and one-sleeve. The latter allows you to change the equipment more quickly.
The hex chuck is designed only for working with bits, but you can trick and use drills with a hex shank. An alternative is to use the removable keyless chuck that comes with some models. The hexagonal chuck allows you to quickly change the bits, they are held by a magnet or a special lock, you need to make a little effort to change the bit.
Also, when choosing, pay attention to the inner diameter of the chuck, which determines what size a bit or drill can be inserted into an electric screwdriver. Household models, as a rule, allow working with attachments with a diameter of no more than 10 mm, but there are exceptions.
The gears in the gearbox can be plastic or metal. The metal version is naturally better.
If you are professionally engaged in the implementation of repair and construction work, then in the arsenal you can have both types of screwdrivers. However, there is an alternative option. combined models with the ability to power from the mains and the battery, however, their choice is not very large.
These screwdrivers are powered from the mains, and this implies a number of pros and cons.
The advantages of network screwdrivers include:
- higher power, therefore the professional one prevails among the network tool. Household screwdrivers with mains power supply are not produced by all manufacturers;
- there is no need to constantly monitor the battery level and recharge it. plugged in the plug and you can start;
- operating time is not limited by the duration of the battery, there is no need to come off to recharge the battery;
- less weight compared to cordless models, because the design of the tool does not provide for the presence of a battery.
- network binding. When assembling furniture, wires only interfere, and when performing construction work, there is not always access to electricity. In addition, the outlet may be located far away, and then you will have to additionally use an extension cord. When working at heights, cordless screwdrivers are extremely inconvenient.
If you are going to use an electric screwdriver for its intended purpose, then the number of revolutions is not such an interesting indicator. Any household tool easily produces 400-500 rpm, which will be quite enough for tightening screws.
If you need to choose an electric screwdriver with a drill function, then it is better to look towards the tool, where the maximum speed reaches 1200-1300 rpm (usually the second speed). This will be enough for woodworking. For drilling metal, an even higher speed is required (about 3000 rpm, third speed in some models), but in this case it is better to use a full-fledged drill.
Household and professional screwdrivers
From the general name, it is well understood that household screwdrivers are designed for infrequent household work, and a professional tool is an indispensable assistant to a specialist in construction and repair work. These two types of screwdrivers differ in power, chuck size, power supply, availability of additional functions, weight and, of course, price.
Household (amateur) screwdrivers should be taken when you rarely need the tool and will use it for a short time. These devices are lightweight, often battery powered, inexpensive, and do well in tasks such as assembling furniture or changing a lock. The rotation speed is rarely higher than 400-500 rpm, and the torque is usually around 10-15 Nm.
If you constantly make something or are professionally engaged in repairs, and the electric screwdriver will be used almost every day and for several hours, then you need to take a more impressive tool. Professional screwdrivers are more powerful, easily withstand high loads, they will not replace a drill, but if necessary, they can even cope with drilling hard surfaces. Their rotation speed reaches 1300-1500 rpm and more, and the torque is 130 Nm.
To decide which electric screwdriver to choose, you need to soberly assess the future load on it and the type of work being done. functional professional models are not always the best option. On the farm, to perform minor repairs, it is enough to have the simplest electric screwdriver, especially since the for such a tool do not bite.
- Famous brand of electrical equipment.
- The set includes 2 rechargeable batteries.
- Rotation. 1,700 rpm.
- Strong and reliable build.
- Start button lock.
- The package includes a case.
Scope of application of the cordless electric screwdriver
Typically, an electric household screwdriver is used for several purposes, namely:
- Allows you to tighten, as well as unscrew all kinds of fasteners. these can be self-tapping screws, bolts, various screws and so on;
- You can make the necessary holes in different materials, from brick or wood to metal.
Cordless screwdriver drill. what to look for when choosing a tool?
At the same time, there are several other ways to use an electric screwdriver, such methods include the following:
- The tool allows you to stir paint or various building mixtures in a matter of minutes;
- Sometimes cordless screwdrivers are used by fishermen in winter so that they can drill holes in the ice for fishing.
Today, this tool is very often used by people who often perform some kind of construction work or do it professionally. In addition, it allows you to attach drywall and other parts needed during the repair to the walls. If you do not want to spend a lot of time on repairs, then you need to know how to choose the right electric screwdriver for your home.
An interesting fact is that the instrument is made in such a way that it can be used even in places where it is difficult to reach. It is the battery models that are very popular. Mostly, unlike a networked electric screwdriver, they allow you to work even where there is no electrical network. Another huge plus is that this tool is very easy to handle and can be used at any time, thanks to the built-in battery.
This method is similar to the previous one and is perhaps simpler. No need to disassemble the charger, or use a laboratory power supply. You only need:
- Car bulbs;
- Pieces of wire;
- Soldering iron with solder and flux.
If the battery delivers the rated current for several minutes, the voltmeter shows a voltage slightly lower than the rated voltage, and the bulbs do not fade, then the battery is in good order. However, it may happen that for Ni-Cd the current will soon begin to weaken. This is a manifestation of “memory”. In this case, you need to carry out the restoration. Lithium-ion batteries do not have a memory effect, although in theory it exists, in practice it is believed that it simply does not exist.
Should I charge before long-term storage??
If the device is not used for a long time, it should be wisely stored in order to prevent damage to the batteries.
Nickel-cadmium batteries are discharged before storage, but not completely, but partially, until the power is reduced. Before use, they are completely discharged and charged at least three times.
Nickel-metal hydride batteries are stored fully charged, and before starting to work with the tool, they are kept on charge for at least a day. After the device has passed 200-300 discharge-charge cycles, its capacity may partially decrease.
Lithium-ion batteries must not be fully discharged. this will disable the protective circuit. Keeps batteries up to 50 percent full. The number of discharging and charging cycles is not limited, but the duration of their service is no more than two years.
The following can be said about the advantages of this type of battery:
Low battery cost; It tolerates low temperatures well; Keeps the battery fully discharged.
This method requires disassembling the battery case. It is used when the battery or its cell stops delivering good current and recovery attempts fail. One bad link is enough here, since they are connected in series. But to find such an element, you need to check the internal resistance of each of them.
Of course, you need to start with a general inspection of all the cans: are there any cracks, leaks, etc. A defective element will immediately give itself out in appearance.
The current return test is performed using Ohm’s law for a complete circuit (aka the first Kirchhoff’s law). To do this, you need to take a resistance with a nominal value of 10 ohms, designed for 25 watts, and an ammeter. The element under test is short-circuited to a resistance connected in series with the ammeter.
For example, suppose a current of 100 mA is obtained for a 1.2 V Ni-Cd battery. Let’s write it down and re-measure, but not the current, but the voltage across the element. First, we will measure the open voltage, without connecting a resistor, and then connect the resistor and see how much the voltage has dropped. Let the first time it was 1.2 V, and after connecting the resistor it became 1.05 V. Then the internal resistance of this element: This is not too little, if all the elements are like that, then the battery can provide an electric screwdriver with only half the power. The lower the internal resistance, the better the element, but with an indispensable condition: it must give a nominal, or close to this voltage. If the voltage is too low, or very close to zero, then the element is short-circuited, it is not suitable and cannot be restored. If the internal resistance is more than 3 ohms, then you can try to restore (see below) or replace.
The multimeter can be used in two modes: voltage measurement and current measurement. If there are two devices, then this is even better, you do not need to make unnecessary switching.
If the voltage on the battery is normal, but the charge current is small, much less than one ampere, then for a Ni-Cd battery this may mean a malfunction of one of the battery cells. The restoration of the battery of the electric screwdriver is canceled here, repair is needed. For Li-ion, this means that either it is normal, or also a malfunction of one of the elements.
Let the Ni-Cd battery have a nominal voltage of 18 volts. Then it is easy to find out how many elements are inside without opening the case. Knowing the nominal voltage of Ni-Cd 1.2 V, divide: 18 / 1.2 = 15. This means that there are 15 elements in the case. If the voltmeter shows an open voltage of 16.8 V, then this may mean a short circuit of one of the cells, and simply a discharge of a normal battery. Such a battery in a discharged state gives 15 V. If a charged one shows 16.8 V or so, then one of the cells is short-circuited. It will not work either, you will have to replace it.
If the battery passes a current of more than one ampere during charging, and the voltage gradually increases, increasing by 0.1 V every 5-10 minutes, and at the end of the charge the voltage is slightly more than the nominal, then the battery is in order, no recovery is required.
How to choose a drill / electric screwdriver with Ni-Cd battery
Batteries of this type have been used for a long time, they are designed for 1.5 thousand charge-discharge cycles. The advantage of such models is that they can operate at low temperatures, up to 15 ° C, have a low cost and their service life is about 5 years.
As a disadvantage, it is worth noting the long process of charging the battery, which has a lot of weight and memory to charge. In order not to reduce battery life, it must be completely discharged and recharged.
In order to completely discharge such a battery, you can use a flashlight, which is often present as an additional function. Such screwdrivers must be completely discharged before long-term storage.
The most commonly used brushless motors are electronically controlled. Such models have high efficiency, there is no need to change the brushes, so they are easier to maintain and have a long service life. The disadvantage of this type of engine is its high cost.
Cordless electric screwdriver runs on lithium-ion, nickel-cadmium batteries.
To choose the right electric screwdriver, you need to pay attention to its power. There are two parameters:
- soft torque displays the maximum force when twisting or unscrewing, the tool speed in this case is from 0 to 350 rpm;
- when it comes to hard torque, it displays the work of the tool while drilling, the rotational speed is 0-1000 rpm.
The best cordless screwdriver you’ll ever buy
productive and powerful is the electric screwdriver, which has the above indicators. For example: if it is necessary to screw a screw with a length of 70 mm into a wooden surface, a torque of 25-30 Nm is sufficient, but if it is necessary to tighten a self-tapping screw up to 100 mm long, it is necessary to take models with a torque of more than 40 Nm. If necessary, tighten longer self-tapping screws, you must first drill a hole.
Availability of additional features
Depending on the model, screwdrivers can have a number of useful additional functions:
- The hammer mechanism makes it much easier to drill holes in concrete and brick.
- There may be an impulse, this is convenient when it is necessary, for example, to unscrew a stuck screw, but there is no opportunity to press the tool well.
- The presence of a speed regulator will allow using an electric screwdriver as a full-fledged drill, such models can develop more than 3000 rpm.
- If you plan to frequently use the tool to work in hard-to-reach places, then the presence of a backlight will greatly facilitate your work. It is even better if the backlight is located on top of the battery pack, but in some models it is placed above the start button, which is less effective.
How to choose an electric cordless drill with Ni-Mh battery
This type of battery is between the Li-Ion and Ni-Cd models in terms of its performance. The popularity of this type of battery is much lower, this is due to the fact that they are designed for only 1000 charge cycles. The battery also has no memory for charging, practically does not self-discharge, but its main drawback is its large weight.
In order for the electric screwdriver to work properly, after long-term storage, it is recommended to completely discharge the battery and then charge it again. If you plan on not using the battery for a long time, fully charge it before storing.
If you decide to choose an electric screwdriver yourself, you need to pay attention to such a battery indicator as capacity. The higher the capacity, the more work you can do on a single battery charge.
Tool torque indicators will directly depend on the battery voltage: the higher it is, the more powerful the electric screwdriver.
There are network models, but they are more intended for professional use or for one-time household work, dependence on the mains and wires that interfere with work are their main disadvantages.
Features of choosing a cordless electric screwdriver for home and professional use
It is impossible to give universal recommendations for choosing the type of electric screwdriver, in each case there should be an individual approach based on how often and under what conditions the tool will be used.
Cordless Electric Screwdriver: Applications
The main purpose of the tool is to unscrew or tighten fasteners such as self-tapping screws, bolts, screws, etc. It can also be used for drilling holes in various materials, including wood, metal, brick. Some craftsmen use a screw gun, for example, as a mixer, when carrying out construction work or for drilling holes during winter fishing.
To choose a cordless electric screwdriver, you need to know that there are models designed for domestic and professional use.
They differ in that they have different power, battery type, cartridge size and various additional functions.
- Lithium ion (Li-Ion) capture more and more sympathy every year, since they do not have a memory effect. These lightweight and compact batteries are not designed for cold operation and are expensive. With the same weight, they have a capacity 4 times higher than other types.
- Nickel cadmium (NiCd) batteries are the cheapest and most famous of them all. They have a pronounced memory effect, which is not very good. It happens if you constantly charge a fully discharged electric screwdriver. As a result, it takes the value at which you started charging it as the initial one and thereby reduces the capacity of the battery. Also, these batteries are very weighty and voluminous.
- Nickel-metal hydride is light and environmentally friendly compared to nickel-cadmium. NiMH does not have a memory effect. but they cannot work in frost and even at 4 degrees they discharge themselves.
This is one of the most important parameters when choosing an electric screwdriver. This characteristic tells us what kind of force will be used to twist the body (bolt, screw, self-tapping screw). For example, if the self-tapping screw has a length of 6 cm, then you can screw it with a screwdriver with a torque of 25 Nm. But if you try to overpower a 12 centimeters self-tapping screw with the same tool, then either the bit will start to scroll, or the fastener will bend.
Select the torque depending on the area of use of the tool. For domestic purposes, an assistant with a max. moment 20Hm. For prof. operation usually take tools from 90 to 130. However, it is worth noting that the power and time of work on the object depends not only on this characteristic.
This parameter tells about the number of revolutions the tool makes per minute. For ordinary screwdrivers, this is from 600. 1600. The number of revolutions of professional devices is 1700-2300. The parameter is easily adjustable.
This site has an article on the top best cordless screwdrivers. There I scattered the best screwdrivers into 3 price categories and described them in detail. I advise the craftsmen not to buy an apparatus of an unknown company, because miser pays twice.
Some people think that the more a tool weighs, the better it is. In 80% of cases, this is true. With the increase in professionalism, the weight grows. However, there are exceptions, so the mass factor should not be overly trusted. So Bosch GSR 18-2-LI Plus has a mass of 1.1 kg, but belongs to very good tools, and Hammer ACD12LE has a very small area of use, although it weighs 1.4 kg. I can add that it is convenient to work with the ceiling with an electric screwdriver, which has a small mass.
How to choose a cordless electric screwdriver
On this page we will tell you about the basic rules of an electric screwdriver, talk about what average parameters an electric screwdriver has for the home, and what a professional unit.
The main values that deserve our attention in the battery. capacity and voltage. The first property tells how long the battery is able to power the device. For short-term work, 1.5-2A / h should be enough for you. Professional screwdrivers are endowed with a capacity of 4 A / H. Also find out the battery charging speed.
Next, let’s talk about tension. The higher this value, the more power the electric screwdriver has. Household tools have a voltage of 12-14 V, and cool cars from 18 V.
An observant person may notice that the higher the voltage, the higher the capacitance. This was done on purpose, otherwise the screwdrivers would quickly discharge.
Additional functions and features
Some of these little things are very important to people, so I just couldn’t help but include them in the instruction.