Convert Charging From A Screwdriver To A Car

Self-powered screwdrivers with a 12V battery are a very popular tool on industrial fishing lines and at a household level. Its advantage is non-attachment to the outlet network, it is very convenient to carry out drilling and fastening of self-tapping screws. As a disadvantage, the high cost of rechargeable batteries and their relatively short service life. from 3-5 years, with intensive work can be even less. Therefore, many people think about how to make a power supply for a screwdriver with their own hands. When buying and replacing batteries, financial costs can be from 50 to 80% of the initial cost of a new screwdriver. Given their financial capabilities and needs, many consumers are looking for a more economical way to continue to operate old screwdrivers. One of these methods is to remake its power circuit for a 220V power outlet.

General view of the cordless screwdriver

How to remake a cordless screwdriver in a network

Consider the two most affordable ways how to remake a screwdriver with a 12V DC power supply with your own hands quickly and with minimal financial costs:

  • Use a native screwdriver charger;
  • Use a power supply for a screwdriver from the PC system unit.

There are other ways to rework, but they require more practical skills and knowledge in electrical engineering, these are available even to amateurs.

Using a charger for a screwdriver

This is the easiest and most cost-effective way, except for the cost of electricity and solder for soldering contacts.


  • The screws securing the charger housing are loosened, the top cover is removed;
  • To the output contacts of the charger are soldered conductive wires of the power cord. The wires must be flexible, stranded, with a cross section of at least 2.5-4 mm2 to withstand current loads during operation, the cord length is 3-4 m;
Convert Charging From A Screwdriver To A Car

Connect the power cord to the charger output

Brass Solder

  • After the soldering places are ready, you can solder the tinned copper ends of the wires to them, with red insulation on, with blue or black. minus;

This whole procedure can be avoided by removing the terminals from the board and soldering wires to the board in their place. You can remove the power cord from the outlet of the charger through the holes in the case where the charging contacts were located, or make an additional hole commensurate with the diameter of the power cord.

Some are confused by the third contact at the output of the charger, you need to use only two: “12V” and “-12V”. The contact polarity is indicated on the case or on the board, for reliability, you can plug the charger into a power outlet and use a multimeter to check for the presence of 12 V DC output voltage and the polarity of the contacts. The remaining contact is for the sensor for automatic control, disconnection and connection of charging; when the battery reaches full charge, the sensor disconnects the charger. In our case, this function is not needed, the terminal can be left or bite off the board. If you intend to still use this charger for its intended purpose, then you do not need to remove the terminals, solder the wires from the bottom of the board to the conductive tracks.

  • After soldering the wires, the cord is pulled out and the charger housing closes. The opposite end of the cord is stripped, copper conductors are tinned with solder.

Video: Convert Charging From A Screwdriver To A Car

The next stage of work is the preparation of power input contacts on the screwdriver itself:

  • Remove the battery container from the handle of a screwdriver;
  • We open it and remove the galvanic banks of the battery;

Removing galvanic cans from the battery compartment

  • In the housing of the battery container, drill a hole for the power cord;
  • The ends of the wire coming from the outlet of the charger are soldered to the contacts in the battery container from the inside, observing the polarity;
  • The terminals on the container are also made of brass alloy, so if necessary, strip and use solder for brazing;
  • Fasten the wire inside the container to the wall of the housing so that it does not come off when stretched. This can be done with a flexible plastic plate by screwing it to the housing inside the compartment with two screws. Lay the power cord under the plate so that it will be firmly pressed from the inside;

Important! Do not use metal plates as clamps to fasten the wires in the charger and on the screwdriver or use a dielectric gasket (plastic, rubber, cardboard or other insulating material) between the wire and the plate. Otherwise, the metal plate may transfer the cord and cut through the insulating layer, which will lead to a short circuit.

  • The battery container is closed and installed in the handle of a screwdriver;
  • The charger is plugged in if everything is done correctly. The screwdriver will function.

It should be noted that if the polarities are reversed, the disaster will not happen, the screwdriver’s cartridge will rotate counterclockwise, in the direction of twisting. But each product has a reverse switch, therefore, in order not to solder the contacts, it is enough to switch the rotation to the other side. It is recommended to observe the polarities in order not to mislead users, and rotation was carried out in the direction in which the arrows near the switch show.

Using the power supply from the PC system unit

This method is used if there is no native charger for the screwdriver, or if it is faulty and cannot be restored.

An LC 300-ATX P4 switching power supply is considered, at the output of which there are three types of DC voltage: 3.3V; 5V and 12V. 12 volt fishing line can withstand loads up to 15A, this is power up to 180W. This is not less than the issue of rechargeable batteries, but, as practice shows, it is enough to twist the screws into dense wood.

Power Supply LC 300-ATX P4

Alteration sequence:

  • The power supply is removed from the old PC system unit, for this it is necessary to disconnect all buses with connectors that go from it to other boards, its case is unscrewed;
  • The cover of the metal case is opened;
  • Connectors with wires bite at a distance of 15-20 cm from the board;

Important! Do not bite the wires going from the board to the fan. there will be no cooling, and the PSU will quickly fail.

  • On all PSU models of this series, the colors of the wires are soldered according to standards, black. the case, yellow 12V, orange 3.3V, red 5V;
  • We turn the green wire to turn on the power supply to the case (black wire) through the switch;

Wire Termination on LC 300-ATX P4 Board

  • It should be noted that a pulsed power supply unit works efficiently when all its outputs are under load, so you can solder a light bulb, black and red wires, even a 12-volt automobile wire to the 5V output. It will not glow brightly, this is not required, the main thing is that the circuit was under stress. We do the same with the 3.3V line. solder the orange and black wires to the 5-10V lamp. One of these lamps can be displayed on the front panel as an indicator that the power supply is on and power is on;

Conclusion of a wire from BP to a screwdriver

  • On the screwdriver, start the black wire to the minus in the battery compartment and connect the yellow to the plus. Removal of galvanic cans from the battery compartment and soldering of wires are carried out according to the method described previously;

Input 12V line to the battery compartment

  • The remaining excess wires can be bitten off or run for reliability in parallel in one line;
  • After connecting all the wires, turn on the power supply to the network, if everything is done correctly, the screwdriver will work.

It should be noted that there are other ways to assemble power supplies on a transformer that produce a total power of 300-400W. In our case, options were considered that did not require investment and great knowledge. In other cases, when you make the power supply for the 18V screwdriver yourself, the power supply for the 12V screwdriver from the PC will not work. It is possible with certain modifications to increase the voltage to 18 volts, but this requires detailed consideration in a separate article, other options, knowledge of electrical engineering and practical skills will be required.