How to Install a Ratchet on a Screwdriver

A screwdriver can be safely ranked as an instrument that quite often has to be used not only in everyday life, but also for work on construction sites. But, like any complex technical accessory, the product can break. How to repair a screwdriver yourself, we will consider in this text.

Basic parameters of the device and the principles of the screwdriver

Equipment in the construction market, where screwdrivers occupy a separate place, is quite large. Many models have individual criteria, characterized by assembly quality and cost. However, for most models the basic principles of action and internal execution are characteristic.

The basic elements of any screwdriver include:

• The presence of an electric motor;
• Planetary reductor;
• Adjustable function button “Start”;
• Reverse switch;
• Force regulator;
• Power Supply.

The electric motor is powered by a direct current network, structurally presented in a cylindrical shape. Inside is an anchor with brushes and magnets. The peculiarity of the electric circuit of the motor suggests that the direction of the supply voltage flow will be directed to the brushes. When the supply polarity changes, the motor reverses.

A planetary gearbox is an important element capable of converting high-frequency oscillations of the electric motor shaft to low-frequency revolutions of the cartridge shaft. Typically, these parts are made of wear-resistant plastic or metal. Many screwdrivers are equipped with gearboxes at 2 speeds. Switching to the first speed mode is necessary for working with self-tapping screws, and at the second speed it is possible to drill in wood, plastic base or metal.

The “Start” key starts the device. It is able to control the number of revolutions, providing the ability to choose the optimal rotation speed for the cartridge shaft. Accordingly, powerful pressing will drive the engine at high speeds, and when the pressure is reduced, the power criterion will weaken.

The reverse switch is necessary to carry out operations to change the rotational direction of the screwdriver motor. This functionality is convenient to use not only for tightening, but also for unscrewing screws.

Regarding the force regulator, we can say that it determines the tightening speed of the screws. In current models, a 16-step adjustable gradation is provided, which allows with maximum accuracy and convenience to determine which tightening speed is relevant when working with various materials.

The power source of the screwdriver is the overall size rechargeable batteries, where the power of the supply voltage (depending on the model device) can vary from 9 to 18V.

The main malfunctions of screwdrivers and their causes

If at some point you find that your screwdriver does not turn on, then most likely he has some kind of malfunction. Practical experience indicates that instrument inoperability can be observed for two reasons:

• The breakdown is connected with the electronics of the device;
• Damage can be mechanical.

Understanding the objective causes of electrical failure, it is possible to note its characteristic signs:

• The product ceases to respond to inclusion;
• The device has ceased to regulate revolutions;
• The reverse operation failed.

Mechanical problems with a screwdriver include problems with the wear of internal parts, for example, a characteristic rattle of the mechanism is heard. As a rule, a faulty screwdriver will start to make characteristic sounds, where, for example, the bushings were pulled apart or the bearing fell apart. Often this happens on a hammer tool.

How to repair a screwdriver with your own hands?

For example, if the tool stopped turning on, then initially you need to check the battery. If the failure did not disappear when the device was based on charging, it means that you have to arm yourself with a multimeter and start scanning the device in search of the root cause. First of all, take a look at the voltage value indicated on the device case and compare it with the readings on the battery. The data should be approximately the same. If the voltage is underestimated, then most likely the problem is hidden in the charger or battery pack.

For example, the charger can be checked with a multimeter by plugging it into the network, and taking measurements on the terminals of the device at idle. It is important that the voltage criterion is somewhat larger than the nominal. In a situation where there is no voltage, then, clearly, the culprit of the breakdown is the charging unit. Interskol screwdrivers “suffer” this rather frequent problem. In general, correcting a defect will require specific knowledge in electronics or will require the purchase of a new unit.

If a battery problem is detected, for example, with a Makita screwdriver, you can open this unit yourself, where the power elements are located. As a result of the autopsy, it is necessary to conduct a study of the connecting wires and make sure the quality of the soldering. If no visible defects are detected, then using a scanner should measure the voltage in each element. Values ​​should indicate 0.9. 1v voltage power. If a block with a low voltage indicator is found in the row, then it must be replaced.

How to repair a device button?

When everything is in order with the battery and charging takes place without problems, but the tool refuses to be activated, it will check the operation of the device’s button. To do this, you will have to disassemble the device and at its terminals, coming from the button, you should measure the voltage with a multimeter, which is fed to the input of the button. It is necessary to carry out the operation with the active battery. If the signal is on, the battery must be removed and its contacts shorted. On the multimeter, you must switch to Ohm mode. The screwdriver button is clamped all the way and measures the output voltage. If the value of the resistance readings on the device tends to zero, then the button works properly. And this means that the problem should be looked for in brushes or other modules of the electric motor. In case of detection of a signal break, it is recommended to repair the button, thereby returning the screwdriver to the working order of the tools.

Quite often, problems with the buttons are associated with poor contact on the terminals. You can simply perform the procedure of cleaning the contacts with sandpaper and the problem will be solved. The main thing is that in the process of disassembling and assembling the device, do everything carefully without losing parts.

How to repair a screwdriver gearbox?

Gear failure is one of the mechanical problems with a screwdriver. Some of the most common problems with a pressure reducing unit include:

• Physical curvature of the axis of the reduction shaft;
• Obvious defect of the working surface of the gear;
• Failure of the shaft support sleeve or the original bearing;
• Breakage of the pin where the satellites are fixed.

To fix these defects, it will be necessary to physically replace the defective parts, therefore, this type of repair should be entrusted to qualified specialists who are able to correctly and accurately diagnose the breakdown and eliminate it.