Converting an electric screwdriver for mains power
One of the frequent causes of failure of an electric screwdriver, is battery wear, that is, the onset of the moment when the battery ceases to take the charge required to operate the tool. This always happens unexpectedly and always causes bewilderment: all units and mechanisms are serviceable, but it is impossible to achieve results due to lack of power. Repair of battery, as well as the purchase of a new one is not the cheapest way out. But, it is possible to remake the portable model in the network model, working from source of 220 V, and return to work condition. How to do it will be discussed in this article.
The condition for the successful reconstruction of an old electric screwdriver is the serviceability of its main parts: the motor, the gearbox, the start button, and the clamping jaw. Only the power element is subject to modification, so the rest of the “stuffing” must be in working condition.
Of course, as a result of these structural changes, the tool will lose its major advantage of mobility. It will be completely dependent on the availability of electrical point with 220 V voltage nearby. But it will keep working for a long time and even have a number of advantages:
- Cost savings;
- No need for periodic recharging;
- complete elimination of the possibility of loss of functionality of the product after prolonged inactivity.
One way to solve the problem with power is to use extension cords, but this option is not always available. Nevertheless, the power tool will remain useful and can serve in the home workshop.
Mains or cordless? Let’s compare!
Type of power source. the first division of types, which we will consider. In choosing the type of power tool power supply, much depends on the working conditions. After analyzing all the pros and cons of cordless and mains screwdrivers, you will be able to choose a tool for your case.
Mains: the power tool is “powered” directly from the mains.
How to Make a Cordless Screwdriver at Home
One of the main advantages of this type is its independence from time. This means that the electric tool will work for precisely as long as you need it to, and the power, and therefore the performance of the tool will be unchanged. This will be a big advantage if you need to use the power tool for long periods of time. But that’s assuming there’s a power grid nearby and your movements around the job site aren’t too active. After all, when working with power tools is always likely to catch / step on, or even just get tangled in the supply cord. It is also worth considering the type of plug, because the plug and socket must fit together. And if the length of the cord is not enough, then you need to worry about buying an extension cord.
If you plan to use the drilling function with a punch, you will need quite a lot of power, which a cordless tool can hardly develop. There is another important advantage of cordless power tools. With the same power, it weighs less than a cordless tool, because the battery always weighs more than the cord.
Cordless: the energy source for operation. rechargeable battery.
It is a type of portable power tools, that is, you can safely move around the work site without thinking about the wire. But continuous operation is out of the question, because a power source is limited by the capacity of the battery, which requires periodic recharging. There are also some kinds of batteries which, when they run out of power, cause the screwdrivers to produce considerably less power. There is also a difference in price: Cordless tool is much more expensive than cordless tool.
How to turn a cordless electric screwdriver into a corded one
The electric screwdriver battery has “given up its life” again? Tired of spending hours recharging? It is a pity that you can not just plug the most useful tool to the mains. Alas, most modern models are completely devoid of this function. However, with the proper desire and availability of the necessary materials, each owner can make a home-made conversion of an electric screwdriver to work with a voltage of 220 volts. In this article, the master plumber will tell you how to convert an electric screwdriver to a voltage of 220 volts.
Without batteries, a cordless screwdriver becomes a piece of metal. When batteries stop holding a charge, you have to look for new batteries. First of all, it is expensive. the price of batteries is up to 80 % of the cost of a screwdriver and it is more efficient to buy a new tool. Secondly, batteries are not always available. if the model is discontinued, for example. Third, the diligent owner wants to use all opportunities to save money.
Converting a cordless screwdriver to run on mains power is a good way out. What it does:
- The tool gets a new life.
- No more need for batteries that require charging.
- The tool’s torque is independent of the battery charge.
The disadvantage of the converted design is the dependence on the socket and the length of the mains cable.
Since an electric screwdriver requires a much lower voltage than the centralized network, the mains tool requires an electrical adapter. a power supply unit that will convert 220 volts AC to 12, 16 or 18 volts DC. There are several variants of power supply.
Pulsed units. inverter system. Such power supplies first rectify the input voltage, then convert it into high-frequency pulses, which are fed either through a transformer or directly. Voltage stabilization due to feedback is achieved in two ways:
Experienced craftsmen prefer the switched-mode power supply because it is small in size. Compactness is achieved due to the absence of power transformer.
Such power supply source usually has a fairly high efficiency. about 98%. Switching units provide short circuit protection, which ensures the safety of the device, as well as locking in the absence of the load.
Among the obvious disadvantages is the lower power compared to the transformer version. In addition, the action of the unit is limited to the lower load limit, that is, at power below the permissible level the power unit will not work. Users also note an increased level of difficulty in repair compared to a transformer.
Transformers are considered a classic version of a power supply. The linear power supply is a symbiosis of several components:
- Decreasing transformer. The winding of the power device is designed for the mains voltage.
- A rectifier, whose function is to convert alternating mains voltage into direct current. There are two types of rectifiers: single half-period and double half-period. The first has 1 diode, the second has a diode bridge of 4 elements.
The circuit may also include other components:
- A high-capacitance capacitor, necessary to smooth out ripples, located after the diode bridge;
- Stabilizer, which causes a constant output voltage, despite any spikes in the external network
- Short-circuit protection unit;
- High-frequency filter to eliminate interference.
Transformers are popular due to their reliability, simplicity, repairability, absence of interference and low cost.
Among the disadvantages are only bulky, heavy weight and low efficiency.
When selecting or self-assembling transformer power supplies, you should consider that the output voltage should be slightly higher than necessary for the tool. The point is that part of it is taken by the stabilizer. For example, for an electric screwdriver with a 12-volt power supply choose a transformer power supply with an output voltage value of 12-14 volts.
Household or professional
As you know, professional screwdrivers have a higher cost, but this is not accidental. They are made with a large margin of safety, for which higher quality and more expensive materials are used. They also have more power, which makes it possible to screw in longer screws and/or work with tougher materials.
The difference between a professional and a home electric screwdriver is in the life span
To decide whether you need a domestic or professional electric screwdriver, estimate the amount of work you will need to perform. If you start construction or major repairs, you probably need a professional or semi-professional model. If the tool will be needed occasionally. to unscrew/screw something from time to time, a domestic more than enough. With this kind of work, the resource of a pro tool will simply not be in demand. So it is not very difficult to choose an electric screwdriver by this criterion.
There is a way out. converting an electric screwdriver into a mains one
Yes, you lose one of the advantages of a cordless tool, mobility. But for work indoors with access to 220 volts, this is a great way out. All the more so that you give a new life to a broken tool.
There are two concepts on how to turn a cordless electric screwdriver into a corded screwdriver:
External power supply. The idea is not as absurd as it may seem. Even a large and heavy step-down rectifier can just stand next to the socket. You are equally attached to the power supply, and to the plug plugged in. And the low-voltage cord can be made of any length;
IMPORTANT! Ohm’s law says that with the same power, decreasing the voltage increases the amperage!
Accordingly, the power cord for 12-19 volts should have a larger cross section than for 220 volts.
Inexpensive screwdrivers for those who do not use the tool very often are good. But, as practice shows, for the time being. Most of them have a battery that fails quite quickly and sometimes they just don’t have enough power. A simple tool modification will help to solve this question. What you get is an electric screwdriver that runs directly on a car battery.
To modify an electric screwdriver with your own hands, prepare:
- the electric screwdriver itself;
- A long Phillips screwdriver;
- battery clips with wires;
- wire cutters;
- soldering iron;
- duct tape.
Step 1. Before you begin, you must completely disassemble the tool. Use a thin long screwdriver for this.
Step 2. First remove one half of the housing and leave the other half with its internal contents in its original form. Remove the battery from the housing. Your electric screwdriver from the inside may look a little different. Here it depends on the manufacturer. Be sure to find the positive and negative electrodes. You will need it for further work.
Note the location of all the internal parts of the tool and take them out of the housing carefully.
Step 3. The bottom part of the plastic housing, which acts as a support, safely cut off with a file. In a modified electric screwdriver, this part will be superfluous. Try to cut the parts symmetrically on the two halves of the tool.
Step 4. Strip the ends of the wires on the battery clamps. Use a sharp knife to do this. If your wires are too long, cut off the excess with the wire cutters and only then strip it.
Step 5. Connect the wires to the electrodes. In this case, the design was a bit unusual, so it was enough to put the wires in the clips and fasten them with duct tape. In most cases you will need to use a soldering iron and solder to make connections. Be prepared for that in advance.
Step 6. Reassemble the electric screwdriver. Insert the internal contents, wires with clips lead out. Reassemble the case and fasten it with the screws. At the bottom, where the stand was, secure everything with duct tape, covering the hole that was created with it.
Inexpensive screwdrivers for those who do not use the tool very often are good. But, as practice shows, for the time being. Most of them have a battery that fails quite quickly, and sometimes they simply do not have enough power. To solve this issue will help a simple option of modifying the tool. The output is an electric screwdriver that runs directly on the vehicle battery.
To modify the electric screwdriver with your own hands, prepare:
- The electric screwdriver itself;
- A long Phillips screwdriver;
- battery clips with wires;
- wire cutters;
- soldering iron;
- duct tape.
Step 1. Before you begin, you must completely disassemble the tool. Use a thin, long screwdriver.
Step 2. First remove one half of the housing and leave the other half with its internal contents. Remove the battery from the case. Your electric screwdriver might look a little different on the inside. It all depends on the manufacturer. Be sure to find the positive and negative electrodes. This is what you need for your further work.
Memorize the location of all the internal parts of the tool and carefully remove them from the housing.
Step 3. Feel free to cut off the bottom part of the plastic housing that acts as a support with a file. In a modified electric screwdriver, this part will be superfluous. Try to cut symmetrically on both halves of the tool.
Step 4. Strip the ends of the wires on the battery clamps. Use a sharp knife for this. If your leads are too long, cut the extra sections off with wire cutters, and only then file them.
How to convert a cordless screwdriver for 220 volt operation?
Methods for converting a cordless screwdriver to mains power vary in complexity, most often requiring you to connect the electric screwdriver directly to the charger. Connecting the charger from a laptop requires little knowledge, to install a computer power supply unit you need to be friendly with the soldering iron, and to reconfigure the Chinese unit the master should be able to handle measuring tools. Be aware that the native power supply of an electric screwdriver is not usually designed to connect the electric screwdriver directly, its power is designed only to charge the battery.
How to connect an electric screwdriver directly to the laptop charger
This method requires a minimum of technical knowledge. If there is a need to convert the screwdriver in the network, you can help you unnecessary charger from a laptop, as it has similar characteristics and easily found in any home. First you need to see what the output voltage of the battery charger. 12-19V chargers will work.
A new battery for an electric screwdriver sometimes costs the same as a new tool! The average lifetime of a battery in an electric screwdriver is about 3 years. After that it needs to be changed. But, as practice shows, in some cases it is easier and cheaper to convert a cordless electric screwdriver to run on 220 V mains. You will give the tool a new life and you will save money. The only limitation that such an updated electric screwdriver will have is the need to plug it in before using it. But there is an opportunity not to stop work while recharging the battery.
Is it worth it to transfer to the network
Many people may not understand why they would want to convert a tool to mains power. In fact, over time, the battery weakens and sooner or later the power element needs to be replaced. This has been shown to be expensive, and finding a quality part can take time and finances. If you switch the electric screwdriver to work on the mains, you can:
The latter depends on the battery charge. If you plug it in, it will have the same power. The only disadvantage of mains operation is the dependence on the length of the cord. Therefore, the design below will consider the removable element.
Self-powering the screwdriver
The hand-held tool can also be used in a building without electricity. In such cases, the device is connected to the car battery or any other power source suitable for the work of the screwdriver.
To connect a car battery, you need to take a wire with crocodile clips, bare one end and solder directly to the contacts of the electric motor tool. The other end is clamped to the battery terminals, observing the polarity.
The connection principle of a portable battery is similar to that of a car battery. Only the ends of the wires are fitted with copper clamping terminals suitable for attachment.
Electric tool lasts much longer than cordless tool. That is why you should not throw the screwdriver away when the batteries have run out of power. The handy man will be able to convert his power tool to mains power, thereby prolonging its life.