How to repair a screwdriver with your own hands

How to repair a device button?

When everything is in order with the battery and charging goes without problems, but the tool refuses to be activated, then it will check the health of the device 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 comes at the input of the button. It is necessary to carry out the operation with an active battery. If there is a signal, then the battery must be removed and its contacts must be short-circuited using the clips. 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. This means that the problem should be looked for in brushes or other modules of the electric motor. If a signal break is detected, the button is recommended to be repaired, thereby returning the screwdriver to the working order of the tools.

Quite often, problems with buttons are associated with poor contact at the terminals. You can simply perform the procedure for 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

A screwdriver can be safely ranked as a tool 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. We will consider how to repair a screwdriver on our own in this text.

The main malfunctions of screwdrivers and their causes

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

  • the breakdown is associated with the electronics of the device;
  • breakage may be mechanical.

Understanding the objective causes of electrical breakdown, one can note its characteristic signs:

  • the product stops responding to switching on;
  • the device has ceased to regulate the speed;
  • reverse operation failed.

Mechanical problems with a screwdriver include problems with wear of internal parts, for example, a characteristic ratchet of the mechanism is heard. As a rule, a faulty screwdriver will begin to make characteristic sounds, where, for example, bushings have been worn out or a bearing has collapsed. This often happens on a hummer instrument.

Basic parameters of the device and principles of operation of the screwdriver

The equipment in the construction market, where screwdrivers take a separate place, is quite large. Many models have individual criteria, assembly quality and cost. However, most models are characterized by basic principles of action and internal performance.

The basic elements of any screwdriver include:

  • the presence of an electric motor;
  • planetary reductor;
  • adjustable function button “Start”;
  • reverse switch;
  • effort regulator;
  • Power Supply.

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

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

The “Start” button starts the device. It is able to control the number of revolutions, providing the ability to select the optimal rotation speed for the chuck shaft. Correspondingly, pressing forcefully will power the engine at high rpm, and as the pressing force decreases, the power criterion will weaken.

The reverse switch is required 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 unscrewing screws.

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

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

How to repair a screwdriver with your own hands?

For example, if the tool stops turning on, then initially you need to check the health of the battery. If, when basing the device on charging, the breakdown has not disappeared, then you will 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 measurement readings on the battery. The data should be roughly the same. If the voltage is too low, then most likely the problem is hidden in the charger or battery pack.

For example, the charger can be checked using a multimeter, plugging it into the network, and taking measurements at the terminals of the device at idle. It is important that the voltage criterion is slightly higher than the nominal. In a situation where there is no voltage, then, unambiguously, the culprit of the breakdown is the charging unit. Interskol screwdrivers “suffer” from this rather frequent problem. In general, fixing a defect will require specific knowledge of electronics or a new unit will need to be purchased.

If you find a battery problem, for example, with a Makita screwdriver, you can open this block with your own hands, where the power elements are located. As a result of opening, research of the connecting wires should be carried out and the quality of the soldering should be ensured. If no visible defects are found, then using a scanner, you 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 a row, then it must be replaced.

How to repair a screwdriver gearbox?

A broken gearbox is one of the mechanical problems with a screwdriver. Some of the most common problems with the reduction unit include:

  • physical curvature of the axis of the reduction shaft;
  • obvious defect of the working surface of the gears;
  • failure of the shaft support sleeve or original bearing;
  • pin breakage where the satellites are fixed.

To correct these defects, it will be necessary to physically replace 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.

What breakdowns occur?

Before disassembling a screwdriver, everyone should study the information about what breakdowns occur most often. Conventionally, every tool, regardless of brand, has typical breakdowns. It is worth highlighting:

  • Battery malfunction.
  • Broken brushes.
  • Buttons fall.
  • The cartridge vibrates or hits.
  • Does not turn on, off.
  • Unstable work.
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Each person is able to cope with such violations himself, but only if he has experience working with measuring tools and a soldering iron. difficulties arise when a gearbox or motor breaks down. In such a situation, it is better to contact the service center. The DIY screwdriver repair procedure has several main stages. The instruction should be the basis.

Button violation

When this part fails, the following is observed:

  • Unauthorized movement.
  • The device does not turn on.
  • No consistency in work.

Several wires go from the button to different components. the battery and the engine. You need to know for sure that the problem is in it:

  • The voltage is checked, it should not be in the button.
  • The battery is removed and the upper motor cable is removed from the button itself.
  • The engine is switched on directly. In the absence of malfunctions, the button is out of order.

Sequence

Fusion 360. Repair a Broken Screwdriver in a quick one day project

  • The cartridge should be disassembled.
  • The flare nut is dismantled (it is double-sex).
  • Remove the clamping jaws by unscrewing them.
  • View fastener threads. In the event of a breakdown, the parts are changed.
  • The cartridge is going. You need to remember the unwinding sequence so that you do not make mistakes during recovery.

When a thread on a cam or nut breaks down, it is difficult to obtain a part. The only way out. remove from another tool. Often, when a cartridge breaks, it is completely replaced. For the Vortex screwdriver, the parsing procedure is identical. When choosing a new part, the old one should be available for example.

Gearbox repair

It includes:

  • Gears.
  • Drove.
  • Satellites.

Two materials are used for manufacturing. plastic, metal. To make repairs, you need to know how to remove the screwdriver gearbox. The gear has cylinders with internal teeth fixed along the entire perimeter. And already on them is the movement of the satellite. The motor transfers the rotational process and the work begins. After detecting a breakdown, it is worth analyzing:

  • Dismantle the cartridge.
  • Remove all fixing fasteners on the body.
  • Disconnect the wires from the gearbox to the engine.
  • Remove plates.
  • Pull out every part in the body. Be sure to follow the sequence.
  • To disassemble the gearbox itself into two parts, the fasteners are removed.
  • Check spring for faster transmission.
  • Remove the retaining ring, washer, bearing (this is a parsing of the coupling).
  • Remove the shaft.

How to disassemble and assemble a screwdriver? To make the assembly easy, each part is arranged in order. When the operation of the screwdriver is accompanied by unusual noises, a breakdown of the gearbox gives such a change. After analysis, it will become clear what has become unusable. The bearings and support bush are usually replaced. If the engine stops after starting, the carrier or gearbox will have to be replaced. If the gear wears out, work is carried out with the gearbox. There are enough breakdowns, but sometimes it is enough to disassemble and lubricate. Do not do too much, otherwise the work will become of poor quality in the future.

How to repair?

Before disassembling the screwdriver, it is worthwhile to roughly estimate what the problem is. After the body is removed, the main units are disconnected. Do not violate the correctness of actions:

  • Battery is removed.
  • The screws that fix the case are unscrewed. There are a lot of them in it, so each screw is carefully removed so as not to break the case.
  • Detach the top. The entire inner set should be removed.
  • Dismantle the button. This is the hardest part because it is fixed to the main propulsion system with wires. They cannot be torn and broken.
  • Remove the speed switch.
  • Dismantle the gearbox, engine, clutch, cartridge. Most often, you have to unscrew the fixing screws, you can not miss any.

Thus, the Vortex screwdriver and others are disassembled. The difference between the systems is negligible. the instruction is suitable for each model. After that, the repair begins.

Cartridge recovery

The part, depending on the brand, has a different attachment to the shaft. There are few ways:

  • Morse taper.
  • The presence of a thread.
  • Thread and screw for fixing.

There is useful information on the bottom of the appliance case. The instructions should be at hand. How to disassemble a threaded chuck:

repair, screwdriver, hands
  • Release the clamps.
  • Remove the screw by unscrewing it clockwise.
  • The hexagon is fixed in the chuck and pressed (you should start or hit the unit). It’s easier to unscrew the part this way.

To disassemble the cartridge, it is worth removing the plugs, depending on the material (it is plastic or metal), a tool is selected. There are many problems with this component:

  • Bolts do not fit straight.
  • Clearance between bit and cam.
  • Cams come out incorrectly.

How to disassemble a screwdriver? DIY screwdriver repair

Repair of any equipment means analysis. A screwdriver is a common unit, it is found in every home. Its breakdown occurs at any time and it is not always possible to contact the master. How to disassemble a screwdriver? This is indispensable in the repair process. All units have an identical device, so the principle of work is approximately the same.

How to repair a screwdriver with your own hands: instructions

DIY screwdriver repair. it is a reality, not a fantasy task. To fix this indispensable tool, you need to prepare the material and strictly follow the instructions below at home.

  • Broken screwdriver
  • Tools
  • the Internet
  • Professional help (if necessary)

Each owner has a set of tools, which he keeps away from children and constantly checks its serviceability. If you need to repair a screwdriver with your own hands, do not despair, since even a beginner will cope with the task at hand. High-quality repair of chargers for a screwdriver will allow you to continue, if necessary, use these useful tools in everyday life and at work. Before talking about repairing, it should be recalled which breakdowns in this case are the most common. Most often, this is the lack of the required speed, the impossibility of switching the direction of rotation, or the unit itself does not turn on at all after it is connected to the network. Yes, this is unpleasant, especially if the owner counted on his help under specific circumstances. Now you have to first repair the screwdriver, and then engage in household repairs of pre-planned objects.

So, if the device itself does not turn on, the first step is to check the condition of its battery. Sometimes just charging it is enough to get the desired result. If the electrical device still does not function after charging, you will have to use a multimeter to measure the battery voltage. As a rule, the operating voltage is written on the case of the unit, and if the indicator is too low, conclusions can be drawn on the multimeter, what is the main reason for the breakdown. For research, the unit must be put into idle mode and only after that perform a control measurement. If the voltage indicator is lower or absent, the whole point is in the charger, which, in the absence of in-depth knowledge of electronics, will simply have to be replaced with a new one. If the check showed that the battery and the charger are in good working order, the screwdriver will have to be disassembled to find another malfunction.

The problem may lie in the radio button itself, the main purpose of which. break the electrical circuit after carrying out basic work with the screwdriver. This is a very convenient and practical device, and in its absence, you would have to constantly run to the outlet, or the mechanism would very soon become unusable due to overheating. If, when measuring with a multimeter, the button is “in the cliff”, then the main task of the wizard. pull it out, replace it with a new one, check the serviceability of the unit. It should be clarified that the ohmic resistance of this element of the electrical circuit at the output tends to zero, thereby indicating that the button is working properly. In this case, you have to continue your search for troubleshooting. The rotation switch may break, which just sets the main direction of the working screwdriver.

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To check the operation of the rotation switch, you need to use the same multimeter. Install the first probe of the measuring product at the input of the element, the second at the output, and then measure the ohmic resistance of the permissible range. If the display shows any number, it means that the button is working properly, otherwise it needs to be replaced urgently. Sometimes it happens that a model, which ideally has several engine operating modes, in practice only works at the maximum without the possibility of adjustment. A dangerous condition, since the mechanism is too hot and very soon the engine itself can burn out, already requiring an expensive replacement. To prevent this from happening, you need to decide what is the cause of the breakdown. There are three options: wear of the brushes, malfunction of the regulating transistor and breakdown of the button itself. It is already known how to determine the integrity of the buttons, and what to do next?

To determine the wear of the screwdriver‘s brushes or the malfunction of the transistor, the electric tool must be opened without fail. The first breakage is visible to the naked eye, while to determine the second one will need all the same help from a multimeter. To prevent such a nuisance from happening in the future, every master should know that brushes have their own shelf life, that is, they are subject to periodic wear, depending on the duration of the operation of the electric tool. In this case, the entire mechanism of the screwdriver is disrupted, and anything can deteriorate. Therefore, it is required to periodically change such short-lived elements for new ones, thereby carrying out elementary prophylaxis of their own equipment at home.

It is important to clarify that the cause of the breakdown may lie not only in the electrical part of the unit, the mechanical “weak points” of such essential tools in everyday life are also well known. For example, armature bushings or bearings may wear out, requiring immediate replacement. But also the working surface of the gears comes into disrepair from time to time; shaft deformation, pin breakage with satellite fastening is not excluded. In such cases, the first step is to purchase a new part, and then proceed to its systematic replacement. If certain difficulties arise in such matters, or a lack of experience reminds of itself, it is best to seek qualified professional help. In this case, the tool will be fixed as soon as possible, but you will have to overpay.

DIY screwdriver repair

About the screwdriver device, read the article Screwdriver device.

The screwdriver may not turn on for three main reasons: the battery is faulty (not charged), the power button is faulty, the engine brushes are worn out, or the anchor itself burned out (very rarely).

Battery. The battery is checked by a simple measurement at its DC voltage terminals with any tester. The output voltage of a working charged battery must correspond to that indicated on the case. 12V, 18V, etc. Otherwise, the battery must be replaced. The charger of the screwdriver may also be faulty.

Regulator of turns and reverse. The screwdriver speed controller is checked with a multimeter in the continuity mode. It should be noted that if the button is fully pressed, the contacts are closed in it and the voltage is supplied to the engine (to reverse) directly, excluding the speed regulator circuit. Two wires from the battery come to the button, after which two wires are connected to the engine through the reverse contacts. The power button may still have three wires for connecting a regulating element (field-effect transistor), which is removed from the body. For continuity, the probes are connected to the input and one of the engine wires (if possible, to the reverse input contacts) alternately, then the button is pressed all the way. The device shows the presence or absence of contact, after which the second input wire is measured. We translate the reverse lever and repeat the measurements. If there is no contact, the button changes.

DIY screwdriver button repair is possible, but only if you have certain skills. It is important to understand that after opening the case, many switching parts will simply fall out of the case. This can be prevented only by smoothly lifting the lid initially and the desired sketch of the arrangement of contacts and springs. If darkened contacts are found, they are cleaned with sandpaper. After assembly, repeated measurements are taken and if the results are positive (there is a contact), the button is installed in its original place.

It should be noted right away that if, after repairing the button, the screwdriver motor starts working when the button is fully pressed, and when the button is pressed smoothly, the speed adjustment does not occur, then the reason should be sought in the adjustment scheme. Most screwdriver repairs in this case come down to replacing the entire button.

If there is no reverse, replace the reverse switch or try to repair it. To do this, open the switch cover and, as is the case with the button, gently lift it up. We check contacts, clean and collect. If the contacts are burnt or deformed, the reverse must be replaced. There are variants of buttons, in which the reverse is assembled inside the button body, in this case the entire button changes.

If, when the button is released, the engine continues to rotate, and before it did not rotate, in this case it is necessary to pay attention to the speed regulator, namely to the regulating transistor. It is necessary to replace either the entire button, or separately the transistor.

Electric motor. If all of the above operations have shown the health of the elements, then it is necessary to check the condition of the engine brushes. To do this, the motor is disconnected from the button, and the multimeter probes are connected to the motor wires. The absence of a small resistance in the chain indicates wear on the brushes, but an armature breakage (winding breakage) should not be ruled out, although this happens very rarely. Usually, in this case, the motor changes entirely, but if the brushes are worn out, it is possible to restore the screwdriver motor independently. On some motors, the brushes can be replaced without disassembling the motor. For others, it is necessary to separate the rear motor cover with brushes from the motor housing.

How to repair Phillips Drill Tip

To do this, it is necessary to bend the rolling of the cover, but in such a way that the edges do not break off, since they will need to be returned to their place after assembly. The flexible wire of the brushes is connected to the holder using spot welding, but the wires of new brushes can be soldered, but only with refractory solder, for example, POS-60. Before assembling the motor, the brushes are removed in the brush holder with a clip made of thin wire, the cover is put in place and the wires are pulled out, thereby freeing the brushes. Next, go around the edges of the case to firmly press the back cover.

Extraneous whistles and squeaks during the operation of the screwdriver can be caused by wear of the armature bushings or a detached magnet that comes into contact with the armature. In the first case, it is possible to extend the life of the engine by dripping a drop of precision instrument oil onto the bushings and then turning on the engine so that the oil is dispersed through the bushings themselves. This method can only extend the life of the engine, but over time you will still have to replace it.

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Reducer. From the long operation of the screwdriver under heavy loads and with lateral pressure, the gearbox shaft is bent, on which the cartridge is screwed, a strong runout appears during the operation of the screwdriver. The bearing bush or bearing of this shaft can also wear out. If only the bushing or bearing is damaged, and the shaft is not bent, then you can try to replace only the worn parts.

It may happen that the engine starts up for a split second and stops abruptly. Everything indicates a breakdown in the gearbox, usually a breakage of the pin on which the satellite is attached. You can try to replace the carrier or the entire gearbox. Failure of the gearbox often occurs due to wear of the gear teeth. A detailed description of the screwdriver gearbox device read here.

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    Replacing brushes

    Graphite brushes are located at the end of the motor from the side of the connection with the button. They can be located inside the motor housing under the rear cover or outside. If at least one of the brushes is 40% worn, replace both. Check your contacts. The following symptoms indicate wear on the brushes:

    • the engine runs in jerks;
    • sounds unusual for normal operation are heard;
    • sparking;
    • the smell of burning.

    When removing and installing the brushes, you need to hold the holders, otherwise, under the action of the spring, they can scatter quite far

    How to disassemble a screwdriver

    The screwdriver is disassembled in the following sequence:

    • Remove the battery.
    • Unscrew the screws connecting the two halves of the case.

    The screwdriver body consists of two parts, connected by a fairly large number of self-tapping screws. in order to disassemble it, you need to find all the attachment points

  • Take off its top.
  • Take out the contents.
  • Disconnect the button.
  • The screwdriver button is integral with the switching mechanism, which is connected to the motor, therefore, when separating the button from the socket on the body, care must be taken not to break the wires

  • Remove the speed switch.
  • Disconnect the motor, gearbox, adjusting sleeve and chuck.
  • In order to disconnect the screwdriver gearbox from its motor, it is necessary to unscrew the four screws located at the contact point of the two plastic covers

    Dismantling and repair of the gearbox

    The main elements of the gearbox:

    • gears;
    • drove;
    • satellites.
    repair, screwdriver, hands

    They are made of metal and plastic. A ring gear is a cylinder with internal teeth all around its circumference. Satellites move along the teeth.

    The first carrier has two gears at both ends. The first sun is the drive gear of the engine. She enters between the satellites of the first carrier. The second sun on the opposite side enters between the satellites of the second carrier. In a two-stage gearbox, the second carrier is connected to the shaft on which the cartridge is put on. The three-stage gearbox has another mechanism. All these parts are located inside the ring gear.

    The engine transmits rotation to the first stage satellites through the sun gear. The first carrier rotates the second stage of the satellites. If there is a third stage, then the second carrier rotates it. The satellites of all stages rotate inside the ring gear. The last carrier rotates the chuck shaft. With each transmission of torque, the speed drops.

    Gearbox disassembly sequence:

    • Removing the cartridge.
    • Unscrewing the case.
    • Disconnecting the gearbox from the engine.
    • Removing the plate.
    • Removing all parts from the body.

    When disassembling the gearbox, all parts are removed sequentially: first the satellites of the first stage, and then the second

  • Unscrewing all the bolts that connect both halves of the gearbox.
  • Correction of spring diameter using pliers to improve gear engagement.
  • Disassembly of the coupling by removing the retaining ring, washers, bulk bearing.
  • Removing the shaft.
  • Lay out all the parts of the disassembled gearbox in order, so that later it will be easier to assemble.

    • If, during the operation of the screwdriver, a grinding sound is heard or it twitches, then the gearbox has defects. During work, you have to make lateral pressure and heavily load the tool. As a result, the gearbox shaft is bent and a noticeable runout occurs. In this case, the assembly is changed in assembly.
    • If the support sleeve and shaft bearing are worn out, they can be replaced with similar ones.
    • Breakage of the pin of the satellite is accompanied by the start and instant stop of the engine. Replace carrier or gearbox.
    • The wear of the gear teeth also requires replacement of the gearbox.

    Often, gearbox repairs are all about cleaning and lubricating. Do not overdo it with grease, otherwise the device will not work well.

    If the battery cannot be removed, the release button is most likely jammed. It is necessary to remove the upper part of the case, disconnect the battery, disassemble it and adjust the button.

    Battery repair

    Three types of batteries are used in screwdrivers:

    • Nickel-cadmium (Ni-Cd). They can be charged many times, but they have a memory effect. If you do not wait for a complete discharge and start charging the battery, then gradually its capacity will decrease. Swing the battery before first use. Discharge and charge it three times to maximize capacity.
    • Nickel metal hydride (Ni-MH). A feature of such batteries is a less pronounced memory effect, but a high self-discharge current. If you intend to store the screwdriver without use for more than a month, be sure to fully charge its battery.
    • Lithium ion (Li-Ion). These batteries charge quickly, but are frost-resistant. They can be charged whenever convenient.

    Store all types of batteries separately from the screwdriver and charger. If not used for a long time, they need to be recharged once a month.

    If the battery does not hold a charge, disassemble it. It consists of several batteries. Check the voltage in each with a tester. The operating voltage is indicated on the case (it is the same for all elements). Replace defective batteries.

    The screwdriver battery consists of several elements, by ringing which you can find and replace those that are out of order