How to convert a cordless electric screwdriver to an electric screwdriver

The process of converting an electric screwdriver

Method : Reconstruction based on the power supply of a laptop

As already mentioned, this method of reconstruction is considered uncomplicated and does not require much time. Beforehand check what output voltage the device is designed for. The optimum choice is 12-19 watts. In the next step, remove unusable batteries from the electric screwdriver device and disassemble the unit.

  • Disconnect the inlet (designed for the laptop connector) and scrap the wires.
  • Take the contacts and simply solder them to the appliance.
  • Select a spot on the device for the wire and drill it. When you are finished, put the construction together and check for proper operation.

Method (reconstruction based on the mains unit from a computer)

For this type of reconstruction, only a “AT” class mains unit is suitable. Such appliances have a vented compartment, as well as on/off buttons. and off. The mains unit is used on many models of computers, so it will not be difficult to find the unnecessary part. Next check the output current, it must be at least 16 volts and the power 300 30 watts.

  • Disassemble the device and find the plate on which the wires are fixed (board).
  • Disconnect protection: find the green electronic component on the circuit board and attach it to any other black wire.
  • Find the construction with two black, yellow and red wires (MOLEX contacts). Attach or solder the extension cord to the yellow and black wire, and connect the other part to the terminals of the electric screwdriver. Now twist the mechanism.

(Reconstruction based on inverter welding)

Reconstruction of an electric screwdriver using inverter welding involves long checks and calculations of the availability of the necessary parts. The process of remaking itself is not complicated, it adheres to the same technology as the previous methods. It is necessary simply to remove the old battery and in its place to attach a corded inlet to the contacts. In the case of an inverter welding you also need to install a secondary coil.

How to convert cordless drill to corded, Black & Decker

On the basis of the article we have read, we can say that it is possible to implement this goal by different methods. To do this, use a number of items, such as: a laptop charger, computer power supply and inverter welding. However, the most successful and uncomplicated reconstruction will be based on the power supply from a laptop. So, not a huge detail will not weigh down the machine and will last a long time. Be careful, all actions involving electrical equipment must follow the safety rules.

See Converting a Cordless Electric Screwdriver to a Network Screwdriver

How to convert a 12 or 18 volt cordless electric screwdriver into a corded one with your own hands

The cordless electric screwdriver was designed primarily for mobility. It is much more convenient to work with the tool without having to worry about whether the wire is long enough or if it will get caught, etc. д.

But without batteries, such a handy tool like an electric screwdriver becomes a simple piece of metal, even though it is fully functional. Battery life is about 3 years, and it is often impossible to find complete or similar batteries on sale. For example, the manufacturer has already stopped producing such a model, and other batteries are not suitable for various parameters.

It is a shame to throw away a tool that you have paid money for, sometimes quite a lot of money. In addition, the cost of batteries is often up to 80% of the price of an electric screwdriver, and it makes more sense to buy a new tool. As a rule, the old tool is sent to a distant shelf and lies there without use. But there is a way to make it work again, to convert it to 220 volt power.

Conversion of an electronic transformer

A fairly simple and compact power supply can be made from an electronic transformer (ET), designed to power low-voltage halogen bulbs.

But in order to use the transformer with a screwdriver, it (the unit) must be modified. Let’s have a look at the classic schematic diagram of the simple ET.

This is the simplest pulse type step-down power supply in a push-pull circuit. The output voltage is taken from the secondary of the output transformer. Of course, the diagram in this picture is not the only one. There are simpler devices, and there are more complicated ones. There is a stabilized output voltage, soft start system and short circuit protection. But what we are interested in is an invariable part of any electronic transformer. So what’s the problem?

The problem is that the output voltage of such PSUs is AC with a frequency of tens of kilohertz, and moreover it is modulated at 50 Hz. It is suitable for incandescent light bulbs, but not suitable for a screwdriver. So it has to be straightened and smoothed out. To do this, we use diode VD1 and two smoothing capacitors. C1 and C2, connecting them according to the diagram below.

H1 lamp serves as a load lamp when the screwdriver is off. It is necessary to start the converter, because it won’t start without the load. The high-voltage electrolytic capacitor can be taken from a computer power supply or any other device, say, a TV with a switching power supply. It is in the case of an electronic transformer. The diode and the capacitor are placed in the case of the tool, and the lamp is set so that it also illuminates the workplace. kills, as they say, two birds with one stone. Such a lamp will be much more convenient than regular light which is switched on only together with the tool. You aim blindly in the dark, then start the screwdriver and see where you hit.

Diode KD2960 is a fast rectifier diode, designed for a current of 20 A and withstands reverse voltage of 1200 V. Its foreign counterpart is 20ETS12. You can’t replace this diode with usual rectifier diode, it has too low response time and at tens of kilohertz it will heat up more than rectify.

But there is a replacement. A Schottky diode, withstanding a current of 15-20 A and a reverse voltage of at least 25 V, is quite good. You can find such diodes in PC power supplies. There they serve the same purpose. The diode must be heatsinked, of course.

Miniature bulb. You can find it in Soviet Christmas lights or use two 6.3 V diodes in series. Assemble the rectifier, place it in the tool housing, lead out through the hole made by the wires, solder one part of the connector. We connect the second one with the transformer wires and the work is finished. As the voltage at the output of electronic transformer is variable, you can ignore the polarity of the connection of wires from ET to rectifier.

As mentioned above, there are transformers that provide a soft start for halogen lamps. Will they fit us? Completely. As soon as we plug it in, it will start and go into operation for 1-3 seconds. After that, the tool can be used without any problems.

Assembly of the mains power supply for an electric screwdriver in a battery case

To remake an electric screwdriver in the mains is convenient, using a case from his battery. In this case the internal stuffing is used:

Converting the Chinese unit to 24 V

Chinese-made PSU with output voltage 24 V (maximum current 9A) is easy to buy in the points of sale of electronic components. Most screwdrivers are designed to work at 12 or 18 V. For this reason it is necessary to reduce the output voltage of the Chinese product to the desired value. This is not difficult to do, even with a superficial knowledge of radio and electrical engineering.

Modernization of the power supply is carried out as follows:

  • solder out the permanent resistor R10 with a resistance of 2320 Ohm, which is responsible for the output voltage;
  • in its place solder an adjustable resistor with a maximum resistance of 10 kOhm, pre-setting this parameter to the value of 2300 Ohm, so that the built-in protection is not triggered when turning on the made device into the network;
  • Feed power to a converted unit;
  • Turn the trimmer to set the desired value of output voltage, checking its value using a multimeter.

To connect the multimeter, you just need to touch the appropriate contacts on the output of the remodeled product with its probes. In this case, the switch of the measuring device must be set to the DC voltage range. If the power tool you are upgrading is designed to work from 12 V, then you should make sure that the current at this voltage does not exceed the maximum value of 9 A. Otherwise, the created device will quickly fail due to overloading.

DIY recessed power supplies

To power an electric screwdriver from the mains, you can also assemble a homemade power supply (IP). You need a 60W electronic transformer, like Taschibra or Feron. They do not need to be rebuilt. The final schematic of the power supply to be assembled is shown in the photo below. On it you can clearly see all the parts with their markings, as well as the main parameters.

The T1 transformer will need to be made by yourself. To do this, proceed as follows:

  • buy a ferrite ring (NM2000), which has dimensions of 28169 mm;
  • Use a file to file the corners;
  • Wrap insulation tape around the ring.

All circuit parts are attached to a plate of aluminum (3 mm or more thick), which will also perform the conductive function. Then assembled the IP install in a case from the battery.

Visual control of the device will be carried out by the LED lamp H1.

You can also take prefabricated parts from energy-saving lamps and other devices. But then the circuit will be different, for example, as in the photo below. To solder them, you need some knowledge of radio engineering.

The diagram above corresponds to a power supply with a ballast lamp, the photo of which in the assembly is shown below. In this case, the bulb performs additionally the function of backlighting.

Using prefabricated blocks when remaking

Inside the old battery case you can put any power supply designed for 220 V, the main thing that it has the right size and the required voltage at the output. Power supply with the necessary characteristics can be purchased at radio markets or in amateur radio stores. To install the purchased power supply for an electric screwdriver instead of the battery, proceed as follows.

  • Preliminarily disassemble the purchased product.
  • You modify it as needed, upgrading it to suit your needs. If necessary, the connecting wires are lengthened, the transformer and the microcircuit are placed separately. For better cooling of the board, equip it with a heat sink.
  • After that, the components are mounted in a housing from the battery pack, which also make holes through which the air in circulation will be dissipated heat.

All the built-in parts inside the case must be firmly fixed.

Particular attention should be paid to the insulation of current-conducting parts between each other this will avoid short circuits.

The degree of modernization of purchased PSU in each individual case depends on the compliance of its original parameters with the required values for the power tool. In order not to make a mistake with the size of the purchased power supply, they take a battery case with them and try on the selected product according to it.

Power supply and a bit of theory

Forums and search in the Internet has suggested to me a standard fate of the person, who has decided to make a network screwdriver with his own hands from a cordless one. a long study of a theoretical part (in case of absence of specialized or general technical education, as it was with me), a quick search for necessary switching power supplies, understanding that to spend a couple thousand, and a choice in favor of buying a new screwdriver for a replacement.

Indeed, let’s look at the theory. My PRORAB was powered by 12V, as indicated by the marking on the motor. The power of the device, traditionally, the manufacturer does not specify, because the figures obtained are not very impressive against the background of wired analogues. Therefore it was necessary to estimate with what parameters the power supply unit for a screwdriver is necessary.

Measuring the power consumption of the motor on failure showed that it would need about 100 VA to show the maximum performance. Approximately the same parameters were advised by guru on the forums for 12 N/m of torque to take a pulser for 8−10А. The cost of such a unit comes out in 1000 r. plus wires, plugs, and other harnesses, which is also a lot.

The way out was found quite simple, if you do not have your own power supply, it will definitely be at work. And in fact, almost every company has its own IT department, which most likely maintains and fixes laptops of its employees. That’s where I headed. In the Electronics Recycle Bin I found a bunch of power supplies with different parameters. There was no outputs for 12V, so I have decided on a Toshiba laptop adapter with outputs 15V/5A, or 75VA, which suits me fine. An interesting option was a Sony with 19V, but I did not want to strain the Chinese so seriously.

How to remake?

Let’s look at how to convert a cordless electric screwdriver to a corded machine using a power supply from a computer. But before you go to disassemble your old computer system or to the store to buy a new power supply, read what is written on the case of an electric screwdriver. Usually you can find the recommended voltage, most often it is 12 V. For this variant it is very easy to find a power supply. But if a larger value is specified, then in some cases the search may take longer. In short, convert only a 12-volt electric screwdriver so you don’t complicate your life.

Tip! Laptop power supplies are rarely suitable. Usually they do not have enough power. So don’t count on this option.

Take a used 500W power supply from an old system or buy the cheapest one from any computer repair store or service.

Buy a power supply

All detailed information about the technical characteristics of the computer unit you can read on the sticker on the side of this part.

Examine the characteristics of the power supply

Then you can begin the remodeling process. Disassemble the native but finished battery and remove all the power elements from it.

Disassemble the old battery

We don’t need the batteries anymore, but keep the terminal blocks and terminals. Carefully remove the last of the batteries.

Remove the terminal blocks Carefully remove the terminals

Solder a 3 mm² wire to the terminals. Bleed it beforehand.

Solder a wire to the terminals This should look like this

Secure the terminals to the terminal block.

Secure the terminals to the terminal block

Take note that the “minus” wire is blue (for example). Insert the terminals according to this information and the symbols on the battery case into the battery case itself.

Insert the terminals into the housing

Hold the terminal holder inside and drill into the case of the former battery at the top with a 3 mm bit.

Make a hole in the case

Remove the chamfer with a bigger drill bit so that the screw can easily be sunk into the plastic (the flat of the screw must not protrude).

Remove the chamfer and screw in the screw

Tighten the screw. That way you can fix the terminals and the wire inside the battery case.

Fasten the terminal blocks inside the case with a screw

Tip:! It is recommended to install a 16 or 25 V capacitor with a capacity of about 10000 mF in parallel to the terminals. This part will help reduce the strain on the power supply.

Drill another hole in the battery case to allow the power wire to come out.

Make a second hole in the battery case

We recommend fixing the wire inside the case so it doesn’t pull on the terminals when you pull the cord while you’re working. For this purpose wrap a few layers of duct tape around the lead from the case at a certain distance. It will prevent the wire from coming out of the hole any farther than necessary.

The duct tape will help secure the wire

Reassemble the battery case back and twist all the parts. The battery plug with the ability to connect the electric screwdriver to the mains is ready.

Assemble the battery case

But that is not all. Now we need to connect our blind plug to the power supply. Look again at the information label on it: it will tell you what color the wires give the 12 volt voltage. Here these are the yellow and black/yellow wires.

Look at the colors of the wires

Connect one black and yellow wire and one yellow wire and two black wires (ground) in parallel. If you only have one 12 volt line, just take two yellow wires and two black.

Twist the two wires together in parallel This is how it should look

Solder the wires to the XT60 power connector.

Solder the wire to the XT60

Solder the wire from the battery stub to the other end of the connector.

Solder the wire from the battery as well

To start the power supply from the computer without the system itself, short the green wire to the black wire to ground. This can be done with a simple paper clip jumper.

Close the contacts with a paper clip

The power supply unit is ready to work. You can turn it on. Excessive wires can be cut off or bundled to get out of the way.

You can cut off unnecessary wires. Don’t forget the insulation

Check that the system works. In general, the electric screwdriver is ready to work from the mains. And since a battery plug was made for such a connection, that is, the wires were not directly connected to the device, you can buy a new battery for such an electric screwdriver if you want, and use both it and this system.

The electric screwdriver is rebuilt and ready for use

convert, cordless, electric, screwdriver

Tip! When soldering wires, the insulation can be provided not only with electrical tape, but also with heat shrink tubing, shrinking the latter with a heat gun.

Materials and tools required

Materials and tools when remaking an electric screwdriver depends entirely on the type of tool and the type of power supply, as well as its features. But if you generalize, there are several basic tools:

  • screwdrivers;
  • pliers;
  • knife;
  • insulating materials;
  • Cable for the power supply;
  • soldering iron and soldering materials;
  • a case for the future power supply.

grass trimmer or lawnmower

The equipment for mowing grass on the site is not cheap. If necessary, it can be made at home using an old electric screwdriver. In addition, it is necessary to prepare and such materials:

  • Plastic pipe up to 2 m long;
  • fasteners;
  • end cap;
  • Motor from an electric screwdriver 12 V and its battery;
  • wire;
  • adapter for the pipe (40-50 mm);
  • button;
  • plastic bucket;
  • alligators (clips);
  • office knife blade.

The working process to create a trimmer for grass or lawn mower consists of several stages. To get the desired result, you need to observe their sequence:

  • Disassemble the housing of an electric screwdriver by removing its motor.
  • Mark the fastening points on the plug and drill them with a drill.
  • Fasten the motor to the plug by screwing it down with 2-3 screws.
  • Solder the motor leads.
  • Install the motor on the mounting location. Run the wires coming from it through the plastic pipe.
  • Mark on the pipe where the push button will be located with a marker. Drill a hole.
  • Connect the wires to the button. You can also solder the alligators to quickly turn on the device using the battery.
  • Make a holder for the battery from the adapter.
  • Install the accumulator by connecting it to the adapter on the pipe.
  • Using blades of a paper knife, make blades for the future equipment.
  • Connect the motor shaft and the nozzle using a terminal clamp.
  • The protective cover can be made from a plastic bucket and connected to the lower end of the pipe.

Such a home-made device can be used for mowing young vegetation.