# How to Make a Power Supply For an 18v Screwdriver

An experienced craftsman in the field of construction always has at hand his indispensable tool. A screwdriver. This is explained by the fact that this device is multifunctional and significantly facilitates the work, which cannot be said about screwing in screws with a screwdriver. However, over time, any equipment, including a cordless screwdriver, loses its effectiveness during operation and already does not work as before. What to do and what to do if you encounter such a problem? Of course, you can buy a new battery, but we are not looking for easy ways, and the price of a new battery is “biting”, so we offer the following alternative. One way out of this situation is to design a home-made power supply for the tool.

### Preliminary work

Before you begin to remodel the device, you need to choose the right size AC power supply for the screwdriver so that it fits in the battery case.

In addition, you need to remove everything in the middle, and measure the inner space, the dimensions of the inner and outer contents differ from each other.

Next, you should study the marking or design on the tool body to determine the supply voltage. If the indicator is other than 12v, the search for a substitute device continues. Then it is necessary to calculate the current consumption of the screwdriver, such parameters are not indicated by the manufacturer. To do this, you need to know the power.

In order to exclude any calculations, you can also choose a power supply by eye. During the purchase process, in addition to the “charging” current, take an interest in the battery capacity. Take, for example, a capacity of 1.2 Amperes, and charging 2.5, then the resulting current should fluctuate approximately between these values. Before you find the missing power supply, it is recommended that you display the following on paper:

1. Dimensions
2. Minimum current
3. Power Required

Electric screwdriver battery circuit

The sequence of actions in the presence of the necessary unit:

1. After you find the optimal power supply and check it for similarity with the declared characteristics, the screwdriver is disassembled, and the old drive is removed. If the body is glued, you can tap a little along the perimeter of the seam with a hammer. Or take a thin knife, putting the point on the seam, gently knock with a hammer. The problem will be solved.
2. The cord, as well as the terminals from the plug, are separated by means of a soldering iron.
3. The place previously taken by the power supply of the cordless screwdriver has the other contents of the case.
4. The cord connected to the network exits through the opening in the housing, and subsequently connects to the power supply with a soldering iron.
5. Soldering again combines the output of the power supply together with the battery terminals. An important rule is polarity.
6. The power supply is connected to the device, after which testing takes place.
7. If the dimensions of the new unit exceed the previous one, it is possible to embed it in the middle of the handle of a screwdriver.
8. A parallel power output establishes a diode of the required power from inside the wire “” between the battery socket, including its output, but with the “-” pole towards the engine. This is done so that the voltage does not come from the mains to the battery.

The transformation of a cordless tool into a device that runs continuously from the network has the following advantages:

• The need for recharging the device is completely eliminated, downtime during long work is reduced.
• Providing a constant current, so that the torque gets a constant value.
• The screwdriver can not be used for a long time, its technical parameters do not deteriorate.

The only drawback of improving the device is the presence of an electrical outlet near the work performed. This problem is easily solved by connecting an extension cord.

### List of materials and tools

Transforming a cordless screwdriver into a network one is quite easy and informative. If you have the necessary skills and all components, it will take a little time. You will find it useful:

• Charger from a screwdriver;
• Outdated (“factory”) battery;
• Soft power cable (multicore);
• Soldering iron, solder;
• Acid;
• Tape for insulation.

### Using the power supply from an old laptop

A laptop battery will do just fine for introducing a power supply for a screwdriver.

1. The screwdriver case is completely disassembled. The old source is removed, the wiring is disassembled by a soldering iron.
2. Connecting the wiring of the new unit to the wiring of the old one that held the past. Observe the polarity!
3. Having activated the “start” button, check the operation of the screwdriver, as well as the correct connection.
1. The case of the screwdriver is provided with a hole where the plug with the charging connector is placed. Now the tool not only works from 220v, but also recharges like a laptop (computer).
2. A new power source is installed in the middle with glue.
3. Other body elements are returned back into place. That’s all, you can get to work!

### Car Battery

The battery can serve as an excellent option for connecting a screwdriver, especially when it comes to work away from the mains. To implement the plan, you need to disconnect the clamps from the working tool and power to the “battery”. Warning! Using the source in continuous mode is not recommended!

### Welding Inverter

To turn the old design into a power supply, you need to make some improvement, namely to add a secondary coil.The advantage of the inverter, when compared with the laptop battery, is immediately noticeable. The design makes it possible to obtain the required voltage, the current strength at the output. The method is good for those who are versed in radio engineering.

### Creating a Transformer Coil

There is also another technology for transforming the device into a network device. Based on the production of a mobile power supply. An elastic wire is connected to the screwdriver, on the opposite side of which there is a plug.

True, you will need to make a separate power supply or take a ready-made transformer equipped with a rectifier. It is important that its parameters coincide with the characteristics of the tool.

It will be difficult for an ignorant person to make transformer coils with their own hands. There is a chance of making a mistake in the number of turns and the selection of the diameter of the wire, so this is not recommended. Today there is a lot of equipment in which the desired transformer is already built. You just need to choose the right one and make a rectifier for it. Semiconductor diodes are used to solder the rectifier bridge. Their parameters must match the device.

### Usage Tips

Experts changing screwdrivers who can easily cope with an established task advise beginners to follow certain rules:

• The power screwdriver is able to function for several hours in a row, so give it a five-minute break to protect against overloads.
• The wire should be mounted in the elbow to prevent interference during operation.
• The power supply must be systematically cleaned of dust and dirt.
• The battery (new) is earthed.
• It is not recommended to use a large number of extension cords.
• Do not use a screwdriver for high-altitude work (starting from two meters and above).

Following these tips will help keep the tool in working condition and extend its useful life.