What torque is needed for a screwdriver. High torque screwdriver: what it is and how to choose it
For some work, you have to tighten a lot of self-tapping screws. You can, of course, do this manually with a screwdriver, but this requires considerable effort and time. To speed up the process, you need to choose a screwdriver. There are quite inexpensive models - household ones - which, nevertheless, greatly facilitate the installation and dismantling of screws. And some can work in drill mode.
Household or professional
As you know, professional screwdrivers are more expensive, but this is not accidental. They are made with a large margin of safety, for which higher quality and more expensive materials are used. In addition, they have more power, which makes it possible to screw in longer screws and / or work with tougher materials.
To decide a household or professional screwdriver you need, estimate the amount of work that will need to be done. If you are starting construction or overhaul probably need a professional or semi-professional model. If the tool is needed periodically - to twist / twist something from time to time, everyday life is more than enough. With such work, the resource of a professional tool will simply not be in demand. So choosing a screwdriver by this criterion is not very difficult.
Rechargeable or mains
Having decided on the class, you will need to decide whether you need a network screwdriver or a cordless one. The disadvantages and advantages of both are obvious: the battery pack has higher mobility and the cord does not interfere with work, but it weighs more. The network does not depend on the availability of battery power, but power supply is not available at all construction sites. V general choice difficult. The decisive moment can be that a cordless screwdriver with a good battery costs decently more than a similar model powered by a network. The difference comes from having a battery - good options are not cheap.
If you decide to choose a cordless screwdriver, pay attention to the cable length. The longer it is, the more convenient it will be to work - you don't have to carry a carrier.
To choose the right battery-powered screwdriver, you need to pay attention to the type of battery. The duration of operation on a single charge depends on this, as well as the order of storage.
- Lithium-ion (Li-lon). Holds a charge for a long time, quickly charges, has a large number of recharges, almost never discharges during storage. Generally, a good option but expensive. Therefore, it is probably more common on professional models, where the duration of work on one charge is important. The disadvantages include the fear of the cold, which is important in our country.
- Nickel metal hydride (Ni-MH). This type of rechargeable batteries is environmentally friendly, small in size and weight, and an average price. Disadvantages - they also do not like low temperatures, they have a short service life - about 3 years. But it is easier to work with such a tool - the hand does not get so tired. When storing the battery, it is fully charged; discharged batteries cannot be stored. During storage, they are discharged, but in moderation.
- Nickel-cadmium (Ni-CD). The main advantages are the low price and the service life of 5 years (the number of charges is about 3000), it is not afraid of frost, that is, you can work outside in winter. Disadvantages - it takes a long time to charge (it takes twice as long as it takes to charge other types of batteries), has a "charge memory". Charge memory is an unpleasant thing. If you put an incompletely discharged battery on charging, then the total capacity of the battery will decrease. It will become less just by the value from which the charge began. Therefore, such a tool must be used until the battery is completely discharged, which is far from always convenient: it cannot always "tighten" the screw, you have to help with your hands or tighten it with a "fresh" battery. Put in storage completely discharged, otherwise the capacity will again decrease.
The cheapest type of batteries is nickel-cadmium, but they have a "charge memory"
So, if you choose a cordless screwdriver for periodic work, a nickel-cadmium battery will also work. If used carefully, it will last a long time. If you start large-scale jobs, it is better to use other batteries - there will be less downtime, work will move faster.
Chuck type
The screwdriver chuck is of two types: key and keyless. The quick-release (usually has three petals) allows you to change the nozzles in a matter of seconds - the cartridge is turned a little by hand, the nozzle is changed, after which it is turned a little in the opposite direction again. In addition, there is one more positive point: in such a holder it is fashionable to install a nozzle of any thickness. The main thing is that the shank fits into the holder.
The same operation with a key chuck requires a special key. It is inserted into a special socket, rotated until the nozzle is free. After replacement, the key turns in the opposite direction. The disadvantage is obvious: you need to have this key handy.
By their structure, keyless chucks can have one or two couplings. If there are two couplings, one of them fixes the chuck, the second - the shaft. If there is only one coupling, then there is a shaft locking button on the body.
It is not difficult to choose a screwdriver according to this parameter - usually everyone converges on quick-clamping ones. They allow you to fix the nozzles of large sizes, although they are a little more expensive, all other things being equal.
Technical specifications
After you have decided on the type of screwdriver and power supply, you need to focus on the technical specifications. They determine which screws and what material you can screw into.
Rotational speed and torque
The torque with which the screwdriver can turn the screw is determined by the torque. It can be quite small for household models - 10-15 Nm, and it can reach 130-140 Nm for professional ones. Therefore, pro screwdrivers can easily and quickly tighten large self-tapping screws and work with hard materials.
But a large torque is not always necessary and not with all materials, therefore screwdrivers provide the ability to adjust the applied force. There is a limiter for this. It is designed as a movable ring, which is located behind the chuck.
There is a mark on the ring, by placing it opposite a certain number, you set the maximum force that the tool can develop. Upon reaching this value, the chuck will scroll to idle - the screw will no longer be tightened. The achievement of this value can be clearly tracked - the ratchet is turned on.
Many models of screwdrivers can work in two modes: the actual tightening of the fasteners and drilling. Such models are called a screwdriver-drill, but now there are most of them. To switch to drill mode, the switch is set to the extreme position (after replacing the nozzle first). At the same time, the maximum speed is turned on, which allows you to drill even rather hard materials.
Screwdriver power
And the boiling moment and rotation speed are a consequence of the power of the electric motor. Therefore, we must also look at this parameter. But here it is necessary to track three values at once: so that the power of the screwdriver corresponds to the speed parameters. Powerful models with good parameters can be found from many manufacturers, but such as Metabo (Metabo), Bosch (Bosch) and Makita (Makita) and other well-known prices for them are very high. There are other brands with similar characteristics, but more affordable prices. For example, RYOBI. The brand is still little-known, but according to reviews it is no worse than the aforementioned famous brands. In order to be able to compare the main characteristics and the price of models of approximately the same power, but of different brands, we will summarize them in a table.
| Model | Tool type | Chuck type / diameter | Maximum idle speed | Maximum torque | Number of speeds | Maximum drilling diameter wood / metal | Battery type, charging time | Battery capacity / voltage | Opportunities | Gadgets | Weight | Equipment | Price |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Bosch GSR 1800-LI 1.5Ah x2 Case | hammerless drill | quick-clamping 0.8-10 mm | 1300 rpm | 34 Nm | 2 | 29 mm / 10 mm | Li-ion | 1.5 Ah / 18 V | power button lock | 1.4 kg | RUB 6.7 - RUB 7.5 | ||
| Bosch GSR 18-2-LI Plus 2.0Ah x2 Case | hammerless drill | quick-clamping 1.5-13 mm | 1900 rpm | 63 Nm | 2 | 38 mm / 13 mm | Li-ion | 2 Ah / 18 V | reverse, spindle lock, electronic overload protection, electronic speed control | 1.49 kg | case, two batteries, charger | 11 thousand rubles - 13.5 thousand rubles | |
| Makita 6347DWDE | hammerless drill | quick-release / 1.5 - 13 mm | 1300 rpm | 80 Nm | 2 | 38 mm / 13 mm | Ni-Cd | 2.3 Ah / 18 V | 1.5KG | 13 tr. | |||
| Makita 6347DWAE | hammerless drill | quick-release / 1.5 - 13 mm | 1300 rpm | 80 Nm | 2 | 38 mm / 13 mm | Ni-Cd | 2 Ah / 18 V | reverse, electronic reverse, electronic speed control | bit socket, power button lock | 1.5KG | two batteries, charger, bit, case | 11.3 tr. - 12 tr. |
| Hitachi DS18DVF3 | hammerless drill | quick-release / 13 mm | 1200 rpm | 45 Nm | 2 | 21 mm / 12 mm | Ni-Cd | 1.4 Ah / 18 V | reverse, electronic speed control | bit socket, additional handle | 2 Kg | case, flashlight, set of attachments | 7.6 tr. - 9.5 tr |
| Hitachi DS18DSFL | hammerless drill | quick-release 2mm / 13mm | 1250 rpm | 41 Nm | 2 | 38 mm / 13 mm | Li-ion | 1.5 Ah / 18 V | reverse, electronic speed control | power button lock | 1.7 kg | RUB 8.7 - 11.6 tr | |
| Metabo BS 18 10mm 1.3Ah x2 Case | hammerless drill | quick-release / 1-10 mm | 1600 rpm | 48 Nm | 2 | 20 mm / 10 mm | Li-ion | 1.3 Ah / 18 V | reverse, spindle lock, electronic speed control | bit socket, spot light, power button lock | 1.3KG | two batteries, charger, case | RUB 7.7 - 8.1 tr. |
| Metabo BS 18 Li 2012 13mm 2.0Ah x2 Case | hammerless drill | quick-release / 1.5-13 mm | 1600 rpm | 48 Nm | 2 | 20 mm / 10 mm | Li-ion | 2 Ah / 18 V | reverse, spindle lock, electronic speed control | bit socket, spot light, power button lock | 1.5KG | two batteries, charger, case | RUB 10.3 - 10.9 thousand rubles |
| RYOBI RCD18021L | hammerless drill | quick-release / 1.5-13 mm | 1600 rpm | 45 Nm | 2 | 38mm / 13mm | Li-Ion | 1.4 Ah / 18 V | reverse, spindle lock, electronic speed control | socket for fastening bits, magnetic holder on the body, spotlight, power button lock | 1.2KG | one battery, charger, bit, bag | 7.1 tr - 7.8t.r. |
| RYOBI R18DDP-0 | hammerless drill | quick-release / 13 mm | 1600 rpm | 45 Nm | 2 | 32 mm / 13 mm | 18 in | reverse, electronic reverse, spindle lock, electronic speed control | socket for fastening bits, magnetic holder on the body, locking of the power button | 1.81 kg | bit (without battery and charger) | 2.7 tr. - 2.9 tr. |
It is worth saying a few more words about the number of work speeds. Not to be confused with the number of rotation speeds. These are two modes of operation that are used when working with different sizes of screws or drills. When working with small screws / drills, you can select a higher speed, when screwing in large screws or drilling large holes, a lower one.
Battery parameters
To choose the right screwdriver with batteries, in addition to the type of batteries, you must select their operating parameters:
To choose a screwdriver for home or professional use and do not regret it, it is necessary to view these parameters. If you have picked up several models, compare them according to these characteristics, because it depends on them how long the interval between the charges of the screwdriver batteries will be.
Additional functions
As usual, these functions are optional, but they greatly improve the usability. Some even raise the price, it is not at all significant, and some are quite noticeable. To choose the most inexpensive screwdriver, you can get by with a minimum - reverse and the presence of illumination of the place of work. The rest are useful, of course, but more suitable for professionals.
Reverse or reverse
The presence of this option allows you to unscrew a screw or a drill stuck in the material. The change in the direction of rotation occurs when the polarity of the power supply is changed, which is carried out through a special button. It is usually installed near the trigger.
Most often, the button for switching the direction of travel has three positions: on average, the tool is locked. This increases safety: if you accidentally hit the lever, the screwdriver will simply stop and not immediately start rotating in the opposite direction.
Illumination of the working area
A very convenient option that does not really affect the price of the screwdriver is the illumination of the work place. In good lighting conditions, it is much easier to control the instrument.
Work area lighting is a useful additional feature of the screwdriver
An LED is built into the handle or the body of the tool near the chuck, which lights up when the start button is pressed. If you want to choose a screwdriver that is convenient to work with, see that there is a backlight for the place of work.
If you decide to opt for a cordless screwdriver, it would be nice to have a battery indicator. These are LEDs different colors- green, yellow, red, which are located on the body. If it is green, the charge is full, if it is red, it is almost discharged.
The location of the indicator depends on the company, but it is usually located on the thickening of the handle, in the same place as the backlight LED, or in the upper part of the case.
Automatic feeding of self-tapping screws
Such screwdrivers are also called shop screws. This option is useful for professionals, especially those who work with drywall, where fasteners need to be installed in small increments. Self-tapping screws are attached to a special tape, tucked into the guides, and automatically fed to the holder.
This option can be implemented in two ways: there are exactly shop screwdrivers (in the photo on the left) and there are nozzles for a regular screwdriver. For home use, the second option is preferable, since the tool can work as a drill or in reverse. A shop screwdriver is a highly specialized equipment for professional use.
Very often on the forums, people ask themselves the question of what power they should choose a screwdriver in order to calmly screw screws or screws of such and such a diameter and length? Or, in other words, what torque should a screwdriver have in Nm for certain tasks?
People get different answers to these questions. Most often, there are offers from "all-knowing experts" to buy expensive semi-professional 18-volt models. They say they can do everything for sure. But is it worth doubling overpaying if it suddenly turns out that the younger models for 10-14 volts are also good? And if there is a difference, what is it?
We will try to briefly talk about the theory and move on to practice.
Theory
Looking at the table, you might think that any of the commercially available screwdrivers is suitable for 5x90 self-tapping screws. But this is not entirely true, as in the practical part of the material.
Let's summarize the theory:
- we do not know from what "ceiling" the figures for the torque characteristics of the screwdrivers indicated by the manufacturer are taken;
- also Captain Obvious suggests that the material used has a noticeable effect on the whole process, as well as the parameters of the screws.
Practice
For practical exercises, we took three different screwdrivers and two different types screws / self-tapping screws and we will screw them into a dry pine bar, simultaneously recording the success of the operation and the time spent.
Here are the names of the screwdriver models and their brief technical characteristics:
Two "oldies" (Bosch and DeFort) were not accidental here. These low-power models will immediately make it clear how much of the above theory was true, and whether absolutely any screwdriver is enough to successfully work with 5x90 mm self-tapping screws and the like. And the middling Hitachi will simply complement the picture and play the role of a kind of modern instrument.
With regard to screws, we did not waste time on trifles and took for a sample thin black 4.8 x 127 mm and, for completeness, powerful white 6 x 150 mm. To screw the latter into a pine beam, presumably, a maximum torque of about 11 Nm is required.
So, as a summary, we suggest you watch a short video in which we captured the whole process.
The thin self-tapping screw (4.8 x 127 mm) turned out to be a feasible task for all screwdrivers, without exception, although it was clear that it was not so easy for Bosch. The time taken by the screwdrivers was: 5.3 seconds for DeFort, 7 seconds for Bosch and 2.9 seconds for Hitachi. We did not set the task of accurately comparing time and repeatability, only the final result was important to us. Therefore, we only made one take for each of the models.
The white "tough guy" was no longer in the teeth for everyone. As in the previous case, DeFort started very cheerfully, but the last centimeter did not submit to him.
Although Bosch solved the problem, the smell of burnt windings made it clear that such loads are categorically contraindicated for this instrument.
Well, for the powerful Hitachi, both screws are like toys. Here's what the stopwatch showed: 13.3 seconds for DeFort (1 cm failed), 20.7 seconds for Bosch and 4.3 seconds for Hitachi. In addition, we note that Hitachi worked during the test at second speed, where the torque is at least a third lower than the maximum stated in the characteristics.
We have one more important remark for the practical part: screwdrivers of old models (Hitachi does not count) participated in our test, which do not have an overload protection system. Majority modern models they have such a system, therefore they will not allow the tool to be mocked as much as it can be seen in the video with the Bosch screwdriver. This also means that the protection system will not allow such a screw to be screwed in completely the first time. You will have to turn on the tool several more times until the next protection operation (usually 1-2 seconds), until the screw is tightened. But in order not to scoff at the tool, of course, you need to buy a screwdriver with a certain power reserve!
conclusions
As for the optimal power (torque) for working with screws 6 x 150 mm, then, in our opinion, it is in the region of 20-30 Nm. You can also say unambiguously that home master, which screws 6 x 150 in the eyes have never seen, there is no point in spending money on "monsters" with a torque of 40 or more N · m. Well, unless only you will be attracted to them b O higher battery capacity in watt-hours (due to higher voltage and more"Cans") or any other features.
The screwdriver is an essential and indispensable tool in the home. With it, you can easily fix the drywall sheet when finishing works, unscrew or unscrew the screw and drill a small hole. And assembling cabinet furniture without a screwdriver is completely inconvenient.
The screwdriver is used both for industrial purposes and at home. Therefore, the choice of a screwdriver must be carried out depending on the purpose.
The scheme of the screwdriver device is the same for both the battery and the network. The only difference is in the power supply parameter of the electric motor, i.e. from the mains 220 or the battery.
The screwdriver consists of:
Specialized electric motor.
- Gearboxes of planetary types, which transfer forces directly to the spindle, where the chuck is located.
- A clutch connected to the gearbox and regulating the torques of the screwdriver mechanism.
- Clamping chuck for bit bits.
- Electronic systems control with a start button and a reverse switch mechanism.
- Power supply in the form of a removable battery.
What is the screwdriver used for?
- Screwing in self-tapping screws, bolts, screws and screws, or vice versa, unscrewing them.- At installation works tighten the anchor and dowels with a screwdriver.
- Wood planks and the bars are drilled with this tool
- Soft metal surfaces can also be drilled with a screwdriver.
Choosing a screwdriver for home
If you are planning a small household repair, then you may well choose a screwdriver for your home. You can easily get by with a conventional model, where all the necessary functionality is already available, and such a screwdriver weighs much less than a professional model. With prolonged work, your hand will not get tired of excess weight.If your repair promises to be delayed, where you will have to screw or mount something on a daily basis, then your choice should lean towards a professional expensive model.
Screwdriver torque
The torque of the screwdriver determines how hard the bit is applied to the screw or bolt being screwed in. With conventional screwdrivers, the torque will be approximately 10-15 Newton / meter. But a professional model can already reach up to 120-140 Newton / meters in torque. It is easy to drill even steel sheets with such a screwdriver. The motor shaft of a professional screwdriver makes 1100-1400 revolutions per minute. But the household model can only count on 300-500 rpm.It is the torque that the screwdriver needs to make it possible without special efforts tighten a thick and long screw. Such tools are used when working with rather hard and dense materials, without fear of breakage of the screwdriver itself.
Screwdrivers differ from other similar power tools in that their torque is easily adjustable. For these purposes, use a special device in the form of a limiter. It is a ring mechanism located near the bit holder. A predetermined force is set using the limiter. The stop mechanism will save the screwdriver from bit wear, breakage of the slot at self-tapping screws and excessive recession of their heads in the surface of materials. The ratchet mechanism of the screwdriver clutch has an overload protection function, allowing the shaft to slip at a critical moment. To switch to drilling modes, it is necessary to move the coupling to the extreme opposite position. In this position, all restrictions on the screwdriver's torque will be removed, and the tool will work like a simple drill. Therefore, it is better to opt for a screwdriver with adjustable torque.
Also, when choosing a screwdriver, consider other nuances. Check how stable the operation of the electric motor is under various loads, whether the declared speed is maintained. Of no small importance for the quality performance of household work is the category of the screwdriver battery, its ability to hold a charge for a long time and the declared power of the tool with a weak charge.
Which screwdriver is better - cordless or mains
As mentioned above, there are two types of screwdriver: mains powered and removable batteries. The cordless screwdriver has a solid mass, and it can only be used near electrical outlet if there is no extension cord. The cordless screwdriver is much lighter and has a great advantage - its mobility. In practice, most people choose a cordless screwdriver.
Choosing a screwdriver battery
To work comfortably with a screwdriver, without frequent recharging of the tool, carefully study the characteristics of its battery before purchasing. Choose a battery that is more powerful. Also buy a spare battery if not included. Pay attention to the recharging time, for professional tools it will be about one hour, and for amateur models - up to 8 hours, depending on the categories of devices for recharging.Battery types for screwdrivers
- Nickel / cadmium,- Lithium / Ion,
- Nickel / metal / hydride.
1.In Lately the most popular are nickel / metal / hydride batteries, which are equipped with European models of screwdrivers. They are marked "Ni-MH", are small in size and weight, do not have a "memory effect". Although they also have drawbacks - they do not like low temperatures and overcurrent. The average number of charging cycles for such batteries is 1500 times.
2. The nickel-cadmium battery is toxic, but the number of recharge cycles reaches 3000. Therefore, screwdrivers now sold in shops and markets, most of them have batteries marked "Ni-Cd". They are still relatively cheap, but frost-resistant. For our domestic conditions, such batteries are best suited. Although this type of battery suffers from increased self-discharge and memory effect, which is a big minus. To store it, be sure to completely discharge the battery or get a battery with a reduced capacity. This type of battery is currently the most optimal on the market for a screwdriver.
3. A lithium-ion battery is rarely built into a screwdriver, because such batteries are sensitive to cold weather, and their capacity is very low. But there are also pluses - recharge cycles reach 3000, and there is absolutely no negative "memory effect", while they are not subject to self-discharge. Although the price of such batteries is quite high.
When choosing a screwdriver, take the time to study the parameters of its batteries. After all, the battery is almost half, or even more than the cost of the instrument itself. Carefully read the data sheet of the screwdriver, comparing such parameters as:
Voltage;
- Battery capacity;
- The presence of a "memory effect";
- Self-discharge of the battery;
The battery of a screwdriver is usually removable and consists of power sources like AA batteries, assembled in a plastic case. The total voltage of such batteries will be summed at the output, and can range from 24-18-14-12 to 10V, which is determined by the number of individual elements, the duration of operation and the power of the screwdriver.
The battery capacity of a screwdriver will depend on the type of cell installed inside the battery. The capacity determines the number of charge cycles and the continuous operation of the screwdriver. Over time, the battery capacity of a screwdriver decreases significantly. Also pay attention to the ratio of the current strength to the time of continuous operation of the screwdriver. The larger this parameter, the better battery will hold its charge.
How to choose a screwdriver, an instruction of 9 steps, an article from which you will learn everything about screwdrivers! Types, capacities, characteristics, applications, comparisons.
Preparing the orchestra for the working season. How to choose a screwdriver - 9 step guide
Today it is not necessary to put a lot of effort to assemble furniture or hang a picture.
- The main thing is to choose the right tool!
This article will help you understand the variety of these tools and buy the screwdriver that is right for you.
1. Purpose of the tool
The screwdriver is only suitable for working with fasteners - an ideal assistant in the assembly of furniture or simple repair work.
There is also a universal tool: a drill-screwdriver, which combines the first two functions - drilling and screwing in.
Cordless screwdriver - serves as a screwdriver, and also allows you to unscrew and re-tighten fasteners. However, its power is lower than that of a conventional screwdriver.
2. Tool type
The classic of the genre is the hammerless drill or screwdriver. Such a tool makes only rotational movements. The hammerless drill is ideal for working with non-hard materials and wood.
- If you need to tighten screws or drill holes in the wall, this is a safe bet.
There are instruments with a blow - in addition to rotational movements, they perform forward and backward translational movements. This allows you to drill in more durable materials: concrete, brick and various metals.
* Impact drills are more versatile - the impact function can always be turned off and move on to work with more fragile materials.
Angle tools are essential for working in confined spaces or hard-to-reach places. Here the gearbox has the shape of the letter "L" and is fixed at an angle of 90 degrees - hence the name.
Some hammerless screwdrivers also have additional angle attachments. For example, it is very convenient when working under the hood of a car.
3. Chuck type
Any screwdrivers are equipped with a chuck. This is the mechanism that holds the bit or drill. In screwdrivers, the chuck is installed under the bits. A bit is a small nozzle, hexagonal on one side and various shapes on the other. To change the nozzle - just remove one and, until a light click, insert the other.
Another important parameter is the chuck diameter. It determines what size drill or bit can be used when working with a tool. For non-professional instruments, a range of 0 to 20 mm is sufficient.
4. Tool power
The power of the tool is determined by the voltage supplied by the battery. It ranges from 1.2 to 36 volts.
Thus, for small jobs, you can buy a power gun with a voltage of 3-6 volts. A screwdriver with a voltage of 10-15 volts is suitable for drilling in non-solid materials.
- When choosing a screwdriver, pay attention to the battery capacity - the operating time depends on it. Average rate is from 1 to 3 A / h.
Often the set includes a second battery for continuous operation, as well as a special base for charging.
5. Maximum torque
Maximum Torque - Determines the efficiency of the tool.
According to this indicator, one can understand how much large diameter and the length of the screw will be able to tighten the screwdriver.
- Power, voltage and maximum torque are interrelated indicators. The higher the voltage, the higher the torque.
For a screwdriver, the maximum torque can be several N / m. This is sufficient for assembling a chair or bracket.
A screwdriver with a torque of 10-30 N / m - to cope with any task. Tighten the screw tightly in the metal rack - no problem!
* Torque of 30-40 N / M - easily allows you to drill a tree.
A device with a maximum torque of 40 N / m and more - easily cope with bricks, concrete and metal surfaces
6. Number of speeds
As a rule, screwdrivers and screwdrivers have only one working speed: from 0 to 800 rpm - this is enough for working with fasteners.
But most drills have 2 speeds:
1st mode with a number of revolutions from 0-400 rpm - mainly used for twisting.
2nd mode with a number of revolutions from 400-1300 rpm - for drilling holes.
- Almost all screwdrivers are equipped with a "reverse" function - for loosening fasteners.
7. Additional information
When working with such tools, reliability and safety are important.
Many models have: blocking the power button; battery protection system against overload, overheating and deep discharge; backlight working area built-in LED flashlight.
When choosing a tool, pay attention to its weight - the higher the power of the screwdriver, the heavier it is.
8. Package contents
The set for screwdrivers, as a rule, includes: a compact plastic or metal case, a battery charger, but sets of drills and nozzles are bought separately, most often.
- Do not forget to protect your eyes when working with screwdrivers and drills - use construction safety goggles.
9. Recipes
If you need a tool for simple work, a small and lightweight screwdriver with a voltage of 3 to 15 volts, with a built-in battery, with a keyless chuck or padded is suitable for you.
For some types of work, it makes sense to buy an angle-type screwdriver - especially if you often repair the car.
If you use tools at home and occasionally: you should buy a screwdriver-drill - shockless or percussion, with a voltage of 15 volts and a torque of 30 N / m, and better - with power and mains support.
Serious renovation ahead?
A percussion drill-screwdriver with a voltage of 20 volts, with a quick-clamping or twisting chuck for large drills, with a torque of 40 N / m and 2 speeds for different operating modes is ideal.
Each instrument has its own special sound! Do you have a whole orchestra?
How to choose a screwdriver - video
Based on the types and technical properties of this necessary for many types construction works tool. Having basic information about what screwdrivers are needed for and how they are used in everyday life or in professional activities, you cannot go wrong with your choice when buying a tool.
Where is the screwdriver used
A screwdriver will perfectly replace a drill, drill through metal and even concrete. The moment is about to come when the screwdriver will practically supplant the screwdrivers.
Screwdrivers are needed to:
... It is easy to tighten or unscrew various fasteners: self-tapping screws, screws, bolts.
... Drill holes in a wide variety of materials. Screwdrivers can make holes in metal, wood, drywall, brick.
But the people found other use for screwdrivers, sometimes completely unexpected. For example, this tool is great for stirring mortars and paints, as well as for drilling holes in ice if you go ice fishing.
What types of screwdrivers are on the tool market
There are enough classifications of screwdrivers. Manufacturers produce household and professional tools, which, in turn, may differ in battery power, in particular, in their power, in the diameter of the cartridge, in the materials from which the gears of the gearbox are made. There are screwdrivers with additional functions. It is clear that the price different types screwdrivers are also different. The price also depends on the brand.
Let's consider how screwdrivers differ in terms of power supply. The devices are divided into two large groups: cordless screwdrivers and electric.
Li-Ion rechargeable batteries
Li-Ion rechargeable batteries are extremely common and popular today. They are used in many instruments, portable devices, and more. What explains such a demand for these rechargeable batteries? Their advantages include:
... Three thousand battery charge cycles.
... The batteries are lightweight and very light.
... The battery charges very quickly.
... The battery does not have a memory-to-charge effect.
But the modern Li-Ion battery also has negative qualities. For example, such a battery only works for three years, which means that it must be used to the maximum during this period, otherwise it will be a pity for the money spent. Li-Ion batteries are quite expensive. Li-Ion batteries are afraid of frost, so if frost resistance is important, then it is better to choose Ni-MH batteries.
Conclusion:
... These rechargeable batteries need to be bought if there is a constant, not one-time work with a screwdriver.
... Full charging and discharging is not recommended for Li-Ion batteries in order for the battery to last as long as possible (discharge - at least 15%, charge - no more than 90%).
... To calibrate the battery, it is sufficient to perform three charge-discharge cycles (cycles are performed in succession).
Ni-Cd rechargeable batteries
These batteries have been used for a long time in screwdrivers and other tools. The number of charge-discharge cycles is one and a half thousand. Such rechargeable batteries last longer than Li-Ion - five years. The use of Ni-Cd rechargeable batteries allows the tool to be used when low temperatures(at frost no more than 15 degrees). The popularity of these devices is also promoted by the fact that their cost is the lowest for rechargeable batteries.
The disadvantages of Ni-Cd batteries include:
... Battery charging takes quite a long time, at least an hour, or even more.
... The battery has a memory-to-charge effect.
... The Ni-Cd rechargeable battery is quite heavy.
Conclusion:
... Because Ni-Cd batteries have a memory-to-charge effect, the batteries need to be fully charged and discharged to enable them to last a long time.
... Full charging is done using a conventional charger.
... A full discharge can be done using a flashlight, which is often included in many kits with a screwdriver.
Battery voltage and capacity
Batteries differ from each other in such important parameters as capacity and voltage.
The unit of measure for capacitance is the ampere multiplied by the hour (Ah). The battery charge directly depends on its capacity. Accordingly, as the capacity increases, the operating time that can be performed without recharging the battery increases.
The voltage of the battery, the unit of which is Volt (V), determines the power of a screwdriver or any other battery-type tool. In the language of professionals, this means that the voltage depends on which indicators will have both soft and hard torques of the screwdriver.
Network (electric) screwdrivers
These screwdrivers are included in the electrical network and are similar to electric drills. The main difference between such a screwdriver and a drill is that you can adjust the torque in it.
Plug-in screwdrivers¸ are great for both occasional home work and professional builders. The screwdriver does not need charging, it works as long as needed from the mains, and this is its undoubted advantage. But there is also a downside to network tools, created precisely by the presence of an electrical network: firstly, electricity is needed to work, and secondly, the tool's wire often interferes, limiting mobility and getting underfoot.
About the chuck and the gearbox in the screwdriver
The screwdriver can be either a quick-release three-jaw chuck (with a clamping range of 1 / 2-13 millimeters), or a chuck with a hex socket with a 1/4 inch shank. The larger size of the keyless chuck makes the screwdriver more versatile.
The tooling changes very quickly in the hex chuck, and this is great convenience if the replacement is done frequently. Often, with such a chuck, drills with a hex shank are used. A combination of a conventional chuck and a hex shank is possible.
The gearbox is needed to transmit the motor rotation impulse to the chuck. The parameters of the torques depend on the gearbox. The gears of the reducer are made of either metal (usually steel) or plastic. In professional screwdrivers, only metal gears are used.
Power
An important technical characteristics screwdriver is its power, depending on the torques (soft and hard). Torques are measured in Nm (newton meters). The tool is more powerful if the number of torque is higher, that is, the screwdriver can drive thicker and longer screws or drills into hard or viscous material.
... Soft torque refers to the maximum twisting or unscrewing of the screwdriver. The soft torque range is 0-350 rpm.
... The indicator of the maximum drilling force is a hard torque. Its range is 0-1000 (maybe much more than 1000) revolutions per minute.
The performance of the screwdriver depends on the maximum torque parameters. For example, with a torque of 25-30 Nm, it is usually easy to screw a self-tapping screw with a length of up to 70 millimeters into a tree. For self-tapping screws up to 100 millimeters long, a torque of more than 40 Nm (for wood) is needed. If the screws are even longer, you first need, as a rule, to drill a hole for it in the material.
Additional functions found in screwdrivers
Many brands produce screwdrivers equipped with additional functions. There are many reasons for both specialized and multipurpose tools, but usually famous manufacturers equip screwdrivers with a number of additions:
... The percussion mechanism is useful if you have to work with socket heads, as well as, if necessary, make a hole with a drill in a brick or concrete.
... Pulse mode (temporary torque boost mode) will make it easier to sink the fasteners into the material, easily unscrew the stuck self-tapping screw or drill if the hammer drill fails. In addition, the impulse mode is very important if you cannot rest against the screwdriver tightly.
... Possibility of illumination, which is an actual addition when working in places where there is poor lighting or no lighting at all. The backlight is usually located above the battery.
... Battery charge indicators and automatic devices that turn off charging.
It is clear that the more additional features, the more expensive the screwdriver. As you can see, there is no one-size-fits-all tool for every task. And you should choose a screwdriver, necessarily assuming the purposes for which it will be used.
What should be guided by when choosing a tool for work at home or in the country
Usually the network model is sufficient for home or summer work. Its weight is small, there is no particular need for mobility. When choosing a rechargeable version, it is better to buy Ni-Cd or Ni-Mh if frequent work is not expected. If you have to work often, a modern Li-Ion battery will justify itself.
As for the torque, the figure of 25-35 Nm is quite normal for household needs. A more powerful screwdriver can also be taken if your financial capabilities allow you.
A battery with a capacity of one and a half to two amperes per hour with periodic use at home or in the country is quite suitable for you.
What should be guided by when choosing a tool for professional use
If you have to use a screwdriver in hard-to-reach places, it is better to purchase a compact model. With long and frequent continuous use of the tool, it is logical to stop at the Li-Ion battery. The maximum torque of the screwdriver should not be lower than 40 Nm. But, of course, the torque can be higher, this is determined by the type of material with which you will be working (it is clear that drywall and brick require different torques).
Why is it worth staying at rechargeable batteries Li-Ion? They ensure a seamless workflow due to their fast charging capability. In addition, their weight is very small, which becomes a very important factor with prolonged use (the hand will get tired less).
To select additional functions, you need to have a clear understanding of the nature of the future work. If you have a hammer drill, as well as a drill, you are unlikely to need all the possible add-ons that modern screwdrivers are equipped with. Therefore, there is no need to overpay for multifunctionality if it is not needed for use.
There are many models of screwdrivers on the screwdriver market now, so you can always find a tool that is suitable for solving your specific tasks. We hope that the article you have read will help you to choose a screwdriver as much as possible.