How Is The Torque Of A Screwdriver Measured
Choosing a screwdriver
The choice of a screwdriver (cordless screwdriver) is a completely solvable task. To do this, you need to know what characteristics you need to pay attention to when choosing. To begin with, we define, household
Choosing a screwdriver
The choice of a screwdriver (cordless screwdriver) is a completely solvable task. To do this, you need to know what characteristics you need to pay attention to when choosing. First, we decide whether we need a household or professional model. If you buy a screwdriver for small housework, for work in the country, etc., then your choice is a household screwdriver. If the screwdriver is expected to be used intensively for a long time, then you need a professional screwdriver. This material will tell you how to choose a screwdriver.
Let’s go back to the main characteristics that you need to know when choosing a cordless screwdriver:
Motor voltage screwdriver. Modern models of screwdrivers have a motor voltage of 7.2V to 24V (Volts). The higher the voltage, the less current is needed to obtain the required power. Accordingly, it is easier to get more power in a screwdriver with an 18V motor, and not 12V or 7.2V. It is worth clarifying that the most common screwdrivers with a 12V, 14V and 18V motor.
Torque screwdriver. Torque is measured in Nm (Newton per meter). In simple words, torque is the force with which your screwdriver twists the screws. The more torque, the more opportunities a screwdriver has. In modern household screwdrivers, the torque is usually 10-28Nm. This is enough for housework. With a torque of 28-30Nm, the screwdriver can screw in 100mm self-tapping screws and drill wood with metal. Speaking of drilling in wood and metal, modern household models are capable of drilling holes up to 20mm in wood and up to 13mm in metal. In professional screwdrivers, the torque reaches 70-140Nm.
Most screwdrivers have a function torque adjustment. It is used where more control is required when performing certain jobs. Adjustment takes place by switching the ring located on the screwdriver body, at the base of the chuck. The numbers on the ring indicate the modes in the torque setting. The drill icon after the maximum number on the ring indicates the drilling mode.
Using the example of tightening self-tapping screws, the function is used as follows:
Tightening screws of different lengths does not need one torque. For smaller screws, a lower tightening force is enough, and for longer screws, a correspondingly greater tightening force. Most likely everyone who has screwed a self-tapping screw into a tree at least once, but sunk it into the material. And where it is necessary that the surface is even and smooth, dents are not permissible. When the so-called “ratchet” is triggered, and this happens when the set torque is overestimated, the screwdriver stops tightening the screw. Thus, allowing more precise control over the work process. This function also protects the motor from overload.
Accumulator battery screwdriver. It is the battery that allows you to work mobile and not depend on the length of the cord. Three types of batteries are used in screwdrivers:
NiCd (nickel-cadmium). Such batteries are the most affordable, but the characteristics are simpler than those presented below. The capacity of such batteries is from 1.2 or 1.5 A / h (Ampere hour). A screwdriver with a capacity of 2.0A / h under the same conditions is able to work longer than a screwdriver with a battery capacity of 1.2A / h. A capacity of 1.2-1.5A / h is enough for home use. And given the current charging time of 1 hour, you will always have a “fresh” battery at hand. Of the minuses: they require a complete discharge.
NiMh (nickel-metal hydride). These batteries are more expensive, but their capacity is also higher from 1.5 to 2.6A / h. Suitable for home use as well as for more complex and prolonged use. Does not require a complete discharge.
Li-Ion (lithium-ion). Batteries are the most expensive, they have a high capacity, which is higher than 3.0A / h. Another advantage of Li-Ion batteries is their light weight. The difference in weight can be up to 40%. Li-Ion batteries do not have a memory effect, which allows you not to wait until the battery is completely discharged.
It should be said that the warranty does not apply to batteries, since they often fail due to the fault of the buyer. If you leave the battery at a low temperature for at least overnight, such batteries may not be able to be used. Store batteries in a warm room.
Speed screwdriver. Different types of work require different turns. For drilling, higher speeds of 1000-1300rpm are required. To tighten the screws, 400-550 rpm is enough. Screwdrivers are available in single-speed, two-speed and three-speed. Switching speeds allows you to work with the speed you need to solve various tasks.
So. If you choose a screwdriver for your home, then a 12-14V screwdriver with a battery capacity of 1.2-1.5A / h and a torque of 15-26Nm is suitable here. Such a screwdriver can handle almost any household work. Household screwdrivers with such characteristics are from 1300 to 3000 rubles. You should not chase a low price, as a rule, the price tag for a screwdriver below 900 rubles indicates that such a screwdriver will not work for a long time. When choosing, pay attention to the recognition of the manufacturer’s company, the terms of the guarantee, the number of service centers. Well, the screwdriver itself should be held in your hand, turned, pressed, etc.
Ratio of torque and screw diameter
When choosing a cordless or mains screwdriver, it is important to correctly determine the ratio of screw diameter and speed. This dependence is not too difficult to determine:
To tighten screws of different diameters, different speeds are required.
- If the diameter of the screw is 6 mm, then the speed during screwing in will be 10 Nm. For structurally soft or hard materials, the frequency will be 25 Nm.
- If the screw diameter is 7 mm, the torque for hard materials will be 27 Nm and for soft materials 11 Nm.
- With a maximum screw diameter of 8 mm, the torque will be 30 Nm.
What does this ratio show? It is possible to determine which torque can be used for a given working screw diameter. The correct choice will not only make the work more efficient, but will also increase the quality, reliability and durability of the equipment. The operation will be completed much faster, the operator will spend less effort.
In network equipment, high power has little effect on the operation process, and batteries drain quickly. Therefore, it is necessary to have spare batteries and the ability to charge those already planted. Usually, manufacturers provide spare batteries for professional tools, but for simpler models, at least one battery will have to be purchased separately. When choosing a screwdriver, it is necessary to take into account the presence of one more function. Reverse. It is necessary when the drill is stuck in the material. This reverse is usually electronic; to control it, you should use a two-position switch, which is located near the start button.
What should be the torque of the screwdriver?
The torque of a screwdriver is a significant parameter that you need to pay attention to when choosing. Be sure to take into account whether the tool will be used for homework or professional. On sale today there are a variety of models that differ in their characteristics.
There are many models of screwdrivers from various manufacturers on the construction market, which differ depending on the power source, parts and functions.
Models of screwdrivers
The screwdriver is the most commonly used tool that is indispensable for construction and repair activities. Manufacturers today offer a variety of models that can be applied under different conditions. This tool is convenient for manual work, it is necessary for tightening / unscrewing screws, screws, self-tapping screws, for drilling and even for stirring building mixtures.
By power source, the tool is classified into:
The cordless screwdriver is powered by the supplied battery.
- Rechargeable models powered by special batteries. They increase the weight of the tool, but make it easier to work in hard-to-reach places.
- Network devices that require connection to the electrical network. They have a limited range due to the length of the cord, although extension cords can be used.
Equipment can be divided into:
- Models for construction / renovation work;
- For production shops, workshops, auto repair shops;
- For industrial enterprises;
- For household use.
There are professional, semi-professional, household models on sale. When choosing, attention should be paid to the torque, which shows what kind of work the screwdriver can handle.
What is meant by torque?
The device is a cordless screwdriver.
Torque is a value that allows you to determine the level of stress on the equipment. Which option should you choose? It is usually equal to 5-10 Nm, this is quite enough for safe and high-quality operation of the tool. This parameter is provided for most household and semi-professional models that can easily cope with tight self-tapping screws, drilling steel, concrete.
What torque should be? You should pay attention to what the tool will be. For example, for a universal device, it is necessary to choose rather high torque values so that the tool copes equally well with any type of work, be it self-tapping screws or structurally rigid materials. If you need a tool only for drilling wood, then you can prefer a model with a small moment from among the household ones. When choosing, you should pay attention to the number of revolutions. For example, 400-500 is enough for screwing in self-tapping screws. For drilling hard surfaces, it is best to use devices with a speed of 1200-1300 per minute..
Which torque is best?
A screwdriver is a tool that is necessary for carrying out various kinds of work. This is not only construction, but also many home repair work, for example, assembling furniture, installing communications. In order to choose the right equipment, you should pay attention to the torque, which determines the comfort and quality of work. For example, you don’t need too powerful a tool to assemble furniture. If you plan to install an interior partition, then you need to take more professional equipment that will perfectly cope with the task.
The torque of such tools must be sufficient to mix even the most viscous mixtures and solutions, to ensure their homogeneity and high quality.
For mixing concrete and other viscous mixtures, special nozzles are used.
If you want to use mortar nozzles, the torque must be sufficient to handle not only low viscosity mixtures, but also high ones. The choice of model depends on the planned work. If a screwdriver is required to be used for mixing liquid mixtures, then the torque may not be too high. If the tool is purchased for working with viscous mixtures, then it is necessary to already prefer professional devices, the turnover of which is high.
Equipment that will be used for a variety of jobs must have a speed controller. Then the torque can be changed depending on what kind of work needs to be done. When choosing a screwdriver, you need to look to ensure that the latch for the control button always works, and not only with maximum effort. In the first case, the tool can be used for any work with the most convenient conditions. The torque value can be changed. It is recommended to buy models that have manual or electronic control. They have a dedicated step-down transformer that works great with liquid mixes when the voltage is low.
What to do when working with viscous mixtures is required?
It is not uncommon for a screwdriver with an impact function to be used for mixing viscous mixtures. To do this, you should choose equipment with high power, since ordinary household ones already with the assigned work may not be able to cope, the effort will not be enough. The torque of this device must be high, i.E. You should buy professional equipment. It is possible to use mechanical built-in gearboxes, they make it possible to use the equipment even at 1st speed. It is necessary to provide a cooling system, it is important to prevent overheating of the motor.
If a screwdriver will be used to assemble shelves or install a conventional curtain rod, then more power is not needed, the torque will not matter much. If the equipment is purchased for frequent use, and it will be necessary to perform various work related to the preparation of mortars, then you must choose from semi-professional and professional tools. They will provide all the required conditions for quality work.
Choosing a home screwdriver, you need to pay attention to its numerous parameters. You should immediately decide whether you need a professional tool or a not too powerful household tool. After that, you should familiarize yourself with the proposed set of functions, technical characteristics, among which torque takes an important place.
How much torque is needed for a screwdriver?
- Tool types
- Torque. What is it?
- Ratio to screw diameter
- Which is better?
- Working with viscous mixtures
Which is better?
A screwdriver is considered a device adapted to perform several types of work. It is useful not only in construction. You can effectively use this device for household purposes: assembling furniture, laying heating pipes and electrical communications. For the correct selection of the tool, they look at the torque, which affects the convenience and quality of the result. For example, a simple screwdriver is suitable for assembling cabinets, and when installing interior ceilings, it is better to purchase a professional powerful model.
Also, screwdrivers (like drills) are often used for mixing building mixtures. To use this function, you will have to additionally purchase a mixer-shaped attachment. This job also requires a lot of torque. If you choose equipment with low power, you will not be able to create a sufficiently viscous, homogeneous mixture or a high-quality solution.
If the screwdriver is planned to be used for different types of work, then it has a speed regulator. When using it, the torque is changed by the master according to the specific type of task. In the process of buying a tool, they also look at the control button lock. It should work constantly, and not only at the moment of pressing, this will provide additional convenience when using the tool.
Below is a table with the characteristics of some screwdrivers, including the maximum torque:
Torque. What is it?
Torque is an indicator by which you can set the force of the load on the screwdriver.
Usually it is in the range of 5 to 10 Nm, which allows you to quickly, efficiently and without problems get the job done.
This load is used for household and semi-professional models.
She easily drills metal plates, screws in large self-tapping screws, and also works with concrete.
How much torque does a screwdriver need to work well? This is determined by the purpose of the instrument. For example, for a universal device, it is better to choose the maximum indicator. This will allow him to work equally well with screws and hard materials.
If the screwdriver is purchased for drilling wood blocks, then the cheapest household model with low torque will do. For example, 400-500 revolutions can easily tighten the self-tapping screw. But for drilling holes in hard surfaces, you need to choose the speed of 1200-1300 per minute.
Ratio to screw diameter
When purchasing a screwdriver, you should also focus on the ratio of screw diameter and speed. This is quite simple to do:
- For a 6 mm screw, the rotational speed during tightening will be 10 Nm. If the structure of the material is very soft or rigid, then the frequency will increase to 25 Nm.
- For a 7mm screw, the torque is 27 Nm for hard surfaces and 11 Nm for soft surfaces.
- For an 8 mm screw (maximum value), a torque of 30 Nm is used.
Choosing the right speed will not only allow you to work more efficiently. It also ensures the high quality, reliability and long life of the screwdriver. With more torque, tasks are completed faster and the foreman does not put much effort.
For mains powered tools, the rotational power has little effect on performance. But battery models sit down much faster. This is why it is recommended for professional tools to always carry a spare battery or quick charger with you. When buying professional tools, there are usually spare batteries included, but owners of household models will have to purchase them themselves.
A screwdriver is an important tool that no construction or repair work can do without. On the modern market, all available types are sold, used for different purposes. This device is especially useful for minor homework. With its help, it is easy to tighten and unscrew fasteners (screws, screws, self-tapping screws), drill, and also mix glue or putty.
By type of power supply, all screwdrivers are divided into:
- Rechargeable, battery operated. Because of them, the weight of the screwdriver becomes larger, but the approach to uncomfortable places is much easier.
- Network: functional when connected to an outlet. Due to the power cable, they have a short range, which can be extended with an extension cord.
Also screwdrivers are divided into groups by purpose. Among them stand out:
- Devices for construction or renovation tasks;
- Screwdrivers for workshops, car centers, manufacturing workshops;
- Tools for industrial plants and factories;
- Models for household (home) use.
Working with viscous mixtures
If you plan to use a screwdriver for mixing mixtures during work, then it is better to purchase a device with high power. It will be difficult for simple household models to complete this task. Mixing requires a lot of torque, which is only found in professional devices. You can additionally use mechanical built-in gearboxes, they will be able to obtain a high-quality result even in the first mode. Also, a cooling system is provided in advance to avoid the likelihood of engine failure.
For household screwing of shelves or fixing curtain rods, a powerful screwdriver is not required, for these tasks the torque is not important. But if you need frequent use of a screwdriver for several types of tasks, you should opt for a professional or semi-professional model.
When buying a screwdriver for home use, several factors and parameters are taken into account at once. They decide in advance whether a professional model is needed, or you can get by with a simple household tool. This will help you plan your budget. Then you will have to study the functionality of the selected device, technical characteristics. The focus is on torque.
In most instructions for using a screwdriver, such an indicator as power is not indicated. However, for those who choose a tool, it is perhaps the most important. And it is not indicated because the concept is, one might say, combined. So what determines the power of a screwdriver? This is, first of all, battery power and torque. In order to assess the power of a screwdriver as a whole, all these indicators must be taken into account.
Let’s consider the power components separately:
– Battery voltage. It determines the power of the engine and the amount of torque, as well as the operating time of the screwdriver. The average power of household screwdrivers is 10.8-14.4 volts (V). However, there are models with batteries up to 36 volts.
– In addition to voltage, it is worth evaluating its capacity, which determines the operating time and is measured in ampere hours. The average battery capacity of a screwdriver is 1.2-1.5 Ah.
– The torque, that is, the rotational force that the tool develops, determines the length and diameter of the screw that the screwdriver is able to tighten. The higher it is, the more screwdriver power. The torque rating differs depending on the material to be drilled. The technical data sheet of the tool usually indicates the size of the maximum possible drilling diameter for various materials. In addition, a distinction is made between hard torque (starting power) and working, that is, constant. A hard moment is always higher than a constant one. It should also be noted that the torque of modern screwdrivers. The value is adjustable, in the technical data sheets, again, it is indicated how many installations the screwdriver has and the maximum possible torque. Provides a maximum torque of approximately 10 to 60 Newton meters (Nm). It is worth noting that, all other things being equal, the power of the screwdriver increases significantly if it has the function of working in a pulsed mode (jerks). The power is increased due to the fact that the hard torque is periodically triggered.
Don’t try to get the most powerful tool. With excess power, you will screw in the screws too hard, the head will be deeper than the surface, which spoils the appearance and makes it difficult to unscrew the screws if necessary.
Let’s summarize. Before choosing which screwdriver power is right for you, you should decide for what purposes the tool will be used. For rare use in a home workshop, a simple low-power tool is suitable, with a voltage of 12V, a capacity of 1.2Ah and a maximum torque of 10Nm. Such a tool can be used when assembling furniture and screwing in small self-tapping screws for attaching home furnishings (curtains, paintings, etc.). The greatest power is achieved with indicators of 36 V, 3 Ah and 60 Nm. Such screwdrivers are considered professional, working with them requires certain skills, the price for them is quite high. In any case, before buying a screwdriver, you should carefully study the technical data sheet and compare all the values given in order to represent what final power is available to your chosen tool.
What is screwdriver torque?
Getting acquainted with the characteristics of any screwdriver, you will surely come across a parameter such as torque, which is measured in newton meters (Nm). Not everyone remembers from the school physics course what this means. And in this article I will try to explain what the torque of a screwdriver is.
In simple terms, the torque of a screwdriver means the maximum force that it can transmit to a screw or self-tapping screw. It is clear that the higher the torque, the greater this force will be.
What does all this affect? To how much, for example, a large self-tapping screw or a screw in length and diameter you can screw into this or that material. And besides, if you take two screwdrivers with different torque and perform the same work with them, then the mechanism of the screwdriver with more torque will wear out less. Therefore, it can be said that the amount of torque also affects the tool life.
What is Newton?
If you write “Newton” with a capital letter, then this is the name of the scientist, after whom the unit of measurement is named, by which force is measured.
Well, when it comes to the unit of measurement, then “Newton” is written with a lowercase letter, and denoted as “H”.
As a unit of measurement, scientifically speaking, 1 N is a force that changes, in 1 second, the speed of a body weighing 1 kg by 1 m / s in the direction of the force.
If it is a little simpler, then we can say this: for a body weighing 1 kg to move and increase its speed by 1 m / s with every second, then a force equal to 1 N must be applied to it.
Still not clear? Then take an object with a mass of 100 g in your hand. This is the force of gravity that attracts this object to the ground and will be approximately equal to one newton. Why about? Because the force of attraction at different points of the Earth is somewhat different and the standard of one Newton will be the force of gravity of a body weighing 102 g, located at sea level on the Earth’s surface at a latitude of 40 degrees.
What is a Newton meter?
Again, to use a quote from Wikipedia, “one Newton meter is equal to the moment of force created by a force of 1 N relative to a point located 1 m from the mowing line of the force action.”
With regards to the screwdriver, I will explain it as follows. A screwdriver chuck has an axis around which it rotates. Take a screwdriver and place it horizontally with its axis of rotation. Then we take an L-shaped metal bar, in which one of the sides has a length of 1 m, and the second (no matter how long) will be clamped in the chuck. So, if the side of the bar, which is equal to 1m, is placed horizontally and a weight of 100 g is suspended on its opposite end from the screwdriver, then we will get a torque acting on the cartridge, approximately equal to one newton meter. And if we hang, for example, a load of 4 kg, we get 40 Nm.
Therefore, if a screwdriver states, for example, that its maximum torque is 40 Nm, then this means that the screwdriver’s motor through the gearbox transfers to the chuck such a force as if we really assembled the above structure and suspended a load of 4 kg. We will not take into account the weight of the bar itself.
This is what the torque of a screwdriver is.
Well, in conclusion, I must say that the maximum torque is achieved when the start button is fully pressed. In addition, on two-speed screwdrivers at different speeds, the torque will also be different. More on the first, less on the second.
Also, screwdrivers have a special regulator that has a scale with marks from 1 to 15, 20 or another number (as the manufacturer decides) and the last mark in the form of a drill (in this position, you can and should drill), which limits the torque. That is, if you set the regulator to one of the numerical marks, then when a certain value of the moment is reached, the screwdriver does not turn further, but clicks. But if you put the regulator in the “drill” position, the screwdriver will not click, but will try to tighten what it turns to the last. At the same time, the above numbers do not mean the actual moment itself, but simply show how much more or less you do it (just to navigate faster when working)
I hope I managed to explain the essence of the torque of the screwdriver. On this I take my leave. Until we meet again!
Screwdriver, how to choose
One of the most common tools among craftsmen is a screwdriver. In terms of popularity, it is located, perhaps, immediately behind the drill, although it includes some of its functions. The main purpose of this tool is to screw in screws, or rather, to screw in self-tapping screws.
Let’s look at the basic requirements to consider when choosing a screwdriver. They are subdivided into two main types, and these are mains, powered by a 220 volt household network, and rechargeable, respectively, from a battery. Since network screws are not widely used, we will not specifically consider them, but just say that many selection parameters automatically become relevant for networked screwdrivers.
How many volts should a screwdriver be?
The battery voltage of a screwdriver directly affects its power. From the course of school physics, we know that power is equal to the product of voltage and current. It follows from this that the higher the operating voltage of the battery, the higher the power of the device. Of the screwdrivers on the market, battery voltages are 6, 12, 18, 24 and 36 volts. This voltage is always indicated by the manufacturer on the product label.
How many watts should a screwdriver be?
This issue was partially covered in the previous paragraph. But it is worth summing up, the more powerful the screwdriver, the more comfortable it is to work with it. It should be borne in mind that the power of the device must correspond to the battery. The power of the battery must be calculated for the energy consumption of the motor, which is built into the screwdriver. If the ratios are wrong, you can end up draining your battery quickly. It should also be noted that the more powerful the device and the more powerful the power source, the higher the weight and dimensions of the tool. Well, as a result. A higher price of a screwdriver. If we consider the power of the battery, then most likely it is more correct to say not the power, but the capacity of the battery. It is measured in ampere hours and is denoted as Ah.
Screwdriver, with which battery to choose?
In household appliances and tools, there are three types of unattended batteries: nickel-cadmium (Ni-Cd), nickel-metal hydride (Ni-MH) and lithium-ion (Li-Ion). The first and second have a huge disadvantage. Memory. Over time, these types of batteries do not fully charge and discharge. This results in a loss of cell power, or, quite simply, the loss of our precious ampere hours. In addition, the average number of charges and discharges is 1000 cycles. With intensive use of the tool, the batteries will quickly fail. There are various ways to resuscitate such containers, but this is quite problematic, and they are not fully restored and not for a long time. Lithium batteries do not have a memory effect, but they do not tolerate extreme temperatures well. But such batteries are more durable and much lighter than their counterparts. The payback for owning a lithium-ion battery will be the higher cost of the screwdriver.
What should be the moment in the screwdriver?
An explanation is needed here. This refers to the tightening torque of the screwdriver, or rather, the torque. For car enthusiasts, the expression “torque” is probably familiar. In order not to load you with definitions, I will simply say. The tightening torque is the maximum constant load on the screwdriver, at which the device can continue to screw in at a constant speed. The higher the torque, the longer and thicker the screws you can “drive” into walls and other obstacles. Moment is measured in newtons per meter and is abbreviated as Nm. It is advisable not to buy screwdrivers with a torque below 10-12 Nm.
Screwdriver, with what speed to choose?
Here you have to define for yourself. If you want to use the device only for driving screws, then this is one thing, and if there is a desire or need to drill something inadvertently, then this device should have completely different characteristics. Speaking about the characteristics, we will mean the rotor speed. For standard screwdrivers, it is about 750 rpm. There are also two-speed models that can be more expensive, but here you already get two speed ranges. For example 750 and 1200 revolutions. Is second speed really important for a screwdriver? It’s hard to say, because the work in both cases will be done. With small volumes of screwing, you will not feel this at all, but the screwdriver in the role of a drill has already completely flashed on the horizon. But here again, the speed of a full-featured drill averages 2400 rpm. If your screwdriver is capable of this, then good. The opposite situation is when they want to get a screwdriver from a drill. This will not really be an equivalent exchange, since the drill does not have a friction clutch. The clutch is a device that is configured to operate at a certain torque value. If you tighten small screws, then set the trigger moment less. Otherwise, at a big moment, the screwdriver will drive the self-tapping screw so deep that this can cause rejection of the wall, board and other parts into which this screw was screwed. The drill has no clutch by default.
Should I take a screwdriver with a punch function?
A hammer drill is a function of a drill and it serves to drill stubborn surfaces such as concrete, brick, etc. If you want your screwdriver to work even for a good drill, then feel free to purchase a model with such a “twist”. Otherwise, this is a redundant function and should not be overpayed for. Be sure to read the article Why isn’t concrete being drilled? Drills burn and break.
Screwdriver, which one to choose?
Precisely, the question posed sounds like a screwdriver of which manufacturer to choose. In this situation, the choice is up to you. We have discussed all of these selection factors. You just have to proceed from the parameters of convenience, price and personal sympathy. We will not list famous brands and tell you about their advantages and disadvantages. You work with the tool. Take a look. Whether it is comfortable to lie in your hand, whether it will not be heavy when performing long work, etc. We are sure you will get what you need!