What types of drill chucks are there and how to choose them correctly. How to change a drill bit in a drill - proven methods! Electric drill how to replace the chuck

Quick-release and keyed

Any craftsman who has a drill on his farm may encounter a situation where the drill chuck begins to hit (the center is lost) and the drill moves from side to side, as a result of which normal work will not work. Or the chuck's jaws are simply worn out, which can happen over time.
In this case, the cartridge should be replaced with a new one. How to choose it correctly?

There are several types of drill chucks. There are threaded ones, some are on a cone, which are simply pushed on and not screwed on. Let's consider them in more detail so as not to make a mistake when choosing.

Threaded chuck.

On thread

It is put on the drill by screwing it onto a threaded pin, which is located on the drill.
There are two main types of threaded chuck. They differ in thread types.
They are marked (1.5-13 M12*1.25) and (1.5-13 1/2 - 20 UNF)

The numbers 1.5-13 indicate the maximum and minimum diameter of the drill shank that can be clamped into the chuck. The minimum is 1.5mm, the maximum is 13mm, 13.5 is also included, I checked it personally. On some chucks the minimum clamping diameter is 2mm.
M12 – means that the hole at the bottom is 12mm.
1.25 or 1/2 - 20 UNF is different types threads, the first is metric, the second is inch.

Choose correctly, the cartridges are not interchangeable, if there is a marking on the cartridge M12*1.25, then take that one. If M12*1/2 – 20 UNF – then only this one. If the inscription is erased, you will have to remove the cartridge from the drill and take it with you to the store.

How to remove it?
To do this, twist the cartridge counterclockwise. Sometimes the cartridge is additionally secured with a screw, which is located in the center,

this screw has a left-hand thread, i.e. unscrews clockwise, and not as usual - counterclockwise. First, unscrew the chuck (spread the jaws), then tighten the screw. After this, you can twist the cartridge itself counterclockwise; its thread is standard. It happens that this is very difficult to do, since over time it is very delayed. To remove, you can use it to grab tightly, for example, take number two. You can use the help of a friend: one holds the neck of the drill with one key, the second twists the cartridge itself with another key. Especially if the drill is old, it’s a little difficult without an assistant.

Cartridge on a cone.

They are put on by simple push-on. There are also several varieties: B10, B12, B16, B18. If there is a letter “B” in the marking on the cartridge, know that it is on a cone and there is no thread at the bottom.
The number in the cartridge marking indicates the diameter of the hole at the bottom. The larger it is, the bigger hole. In chucks B10, B12 you can clamp a drill with a maximum shank of 13mm. And B16, B18 allow you to clamp drills with a shank up to 16mm.
Such a cartridge should be removed by knocking it out of the drill, simply and simply using a hammer.
It is mounted on a special pin - a holder located on the drill.

There are cartridges with key, has quick-release fasteners(in the first photo).
The advantages of quick clamping include the fact that it is convenient to quickly change drills. The downside is that sometimes drills can turn, especially if the shank is cylindrical (round) and not hexagonal, especially when the drill for metal is of large diameter. The load is large, but you can’t tighten it by hand, which can’t be said about the “classic” cartridges, which are tightened with a key. In my opinion, this is much more reliable. The only negative is that you can lose the key, for this it is logical to screw it onto the drill cable with electrical tape so that it is always in its place.

There are chucks with a 1/4" hex shank that can clamp drills from 0.6mm.

You have to remove the chuck from the electric drill to clean or replace it. The dismantling process itself is simple, and sometimes difficulties that arise can be solved. Our guide clearly shows how to properly remove the chuck from a drill with your own hands.

Methods for attaching cartridges

IN hand drills There are two types of drill chuck mounting:

Morse taper - a conical shaft shank and a corresponding hole in the chuck.
Threaded fastening - a thread on a shaft onto which the cartridge is screwed like a nut.

Take a close look at the metal rod between the body and the cartridge. In the case of a threaded fit, the slots for the open-end wrench are usually visible, and the tapered shaft is always smooth.

The method of fastening is also indicated by the markings stamped on the cartridge:

The Morse cone is designated by the abbreviation B10, B12, etc. (B is the cone, the number is the maximum drill size).
The marking of the threaded cartridge contains the designation of the type and diameter of the thread: M13 (metric by 13 mm) or UNF-1/2 (inch by half inch).

Removing the threaded cartridge

For drills with reverse function drill chuck additionally secured with a locking screw visible through the open cams.

The slots on the screw head can be cross-shaped, hexagonal or even star-shaped. Prepare the required screwdriver, wrench or bit. Use a tool with complete splines that fit exactly.

Measure the size of the wrench space on the drill shaft. Most likely, it will be 14 mm for a mid-range tool or 17 mm for a more powerful device.

Prepare an open-end wrench with thin jaws. You can take a suitable one from a bicycle repair kit or grind off the edges of a regular key using sandpaper.

Hold the drill shaft with a wrench and try using a screwdriver to unscrew the screw clockwise (left-hand thread).

Try not to tear off the splines.

If the thread does not work, secure the electric drill chuck in a vice and hit the screw head several times with a hammer through a steel rod.

Now the thread will become more pliable and the screw will come loose.

Difficulties may arise. Try increasing the leverage by holding a hex wrench in the chuck.

As a last resort, use a vice, placing a drill in it as in the photo below.

Move the cartridge from its place by striking the driver secured through the square head.

This method makes it possible to unscrew fairly strongly stuck cartridges.

After cleaning, install the cartridge in reverse order, remembering different directions thread.

Apply a little paint to the threads before tightening the locking screw.

Specifics of cone fastening

In modern hand-held electric drills, the Morse taper is rarely found. Such models are equipped with special pullers, and the dismantling process is displayed in the technical description.

In old Soviet drills, the design of the gearbox made it possible to remove the chuck using rather crude methods. One could try to separate the conical surfaces with a wedge-shaped object, lightly knocking it from different sides.

Another option was to take the drill with one hand, with the chuck facing down, and with the other, apply light blows to the end with a hammer. If that didn’t help, we lubricated the landing site with a penetrating compound (kerosene or WD-40), let it sit for several hours, and tried to knock the cartridge off again.

This method can be used if the shaft bearing is installed inside the housing. For most drills used today, this method is unacceptable, as it can lead to damage to the bearings or gearbox.

When selecting a new chuck, pay attention to the type of fastening, bore diameter and the ability to operate in impact mode, if your drill has this option.

Electric drills use a special device called a chuck to securely hold the drill bits. In household drills, jaw chucks are the most widely used type. With intensive use, they may fail and require replacement or repair. Problems often arise during these operations. So how can you remove the chuck from the drill shaft, disassemble it into its component parts and replace it with a new one?

The role of the chuck in reliable fastening of the drill

Clamping drill chucks for household drills are available in three modifications:

key;
quick-release;
gear-crown.

The body of the key jaw chuck is made in the form of a hollow hardened cylindrical sleeve (collet), on the outer surface of which a rotating adjusting clip is installed.

On one side the cylinder is mounted on the drive shaft of the drill, and on the other side there are cams (petals) for attaching cutting tools (drills, taps, reamers, etc.). When the adjusting ring rotates, the steel cams move along guides using special threads. If they come close to each other, the drill is clamped. If they diverge from each other, the tool is released. The approaching and moving away of the cams depends on the direction of rotation of the holder. Reliable fixation of the drill is ensured by tightening the chuck holder with great force. To do this, use a special key or a quick-clamping coupling with quick-release chucks.

The key helps to firmly clamp the drill and easily unscrew the adjusting collar. Drills of various diameters with a cylindrical shank are fixed in jaw chucks. Most often, household electric drill chucks are designed for drills with a diameter of 0.8 to 10 mm or 1.5 to 13 mm.

Why and when do you need to change? The clamping device must ensure that holes are drilled with acceptable accuracy. But over time, the seats on the shaft and cams wear out, and the cartridge begins to beat. That is, the working area of the drill begins to move from side to side when rotating, and the hole is drilled with deviations both in location and in diameter. Wear on the cams does not allow the drills to be securely fastened, and they stop under load.

There is only one way out - replace the worn cartridge with a new one.

How to replace a drill chuck with your own hands? To attach the chuck to the drive shaft of the drill, a threaded connection or Morse taper is used. electric drill will not always help to suggest a method for securing the drill chuck. This can be indicated by the marking on the cartridge: it is stamped on its surface.

Replacing the conical type of part

The standard size of the Morse cone (according to GOST 9953–82) consists of 9 values: from B7 to B45. How higher figure after the letter B, the larger the diameter of the cone.

Thus, having found the marking “B” on the surface of the cartridge, we can conclude that this is a device with a conical mounting base. With this method of attachment, the cartridge can be easily removed. It is enough to use a drift and a plumber's hammer.

Video: how to remove a chuck with a cone from an electric drill?

Replacing the reversible threaded chuck

To secure the drill clamp to an electric household drill using a threaded joint, two types of threads are used:

inch (for foreign models);
metric (from Russian manufacturers).

The following marking is applied to the surface of the threaded clamping chuck body: 1.5–13 1/2 – 20UNF or 1.5–13 M12x1.25.

Reverse threaded chuck For fixation it has a screw with a left-hand thread. You need to know this nuance when filming broken cartridge.

In order to get to the screw head, it is necessary to recess the cams into the collet completely. As soon as the head of the screw is visible, use a hardened Phillips screwdriver to unscrew it to the right clockwise. Then hold the hex key in your fists and hit it sharply in a counterclockwise direction. After the cartridge is torn from its place, it can be easily unscrewed.

Video: how to remove a chuck from a reverse drill or screwdriver? On other models there are other options for mounting the cartridge on the thread. In some cases, the cartridge is twisted entirely from the threaded end of the shaft. In other cases, the screw can be fixed with a special thin key using a narrow groove. The main difficulty is to move the cartridge from its place when unscrewing.

Sometimes this is very difficult to do. In any case, to remove the cartridge you need: a mechanic's tool, the necessary skill and patience.

Disassembling a drill chuck with a quick-release nut

To clean the jaws and lubricate the moving parts and threads of the cartridge, it must be disassembled. Disassembly is necessary to repair and replace failed parts. Here is a short list and sequence of operations for disassembling the jaw chuck:
The removed cartridge with the conical part up, lined with wooden spacers, is clamped by the coupling in a vice.
The bearing is pulled out. The puck comes out.
The cartridge is removed from the vice.
The adjusting sleeve is twisted from the base by hand. If it does not give in (jammed), then the cartridge turns over and is again compressed by the clutch in a vice. A little machine oil is poured onto the threaded part of the coupling and base. Then, using a gas wrench, the base is skillfully unscrewed from the coupling.
If there is a retaining ring or nut at the bottom, they are removed.
The cams are pulled out of the guide rings and removed from the base cone.
All parts of the drill chuck are carefully inspected. If worn, deformed or broken parts are identified, they are rejected and replaced.
The jaw chuck is assembled in the reverse order. At the same time, all moving parts are lubricated with a special grease. It is best to use the lubricant recommended by the manufacturer.

The procedure for disassembling cartridges of other models may be different. It depends on the type of chuck, its design and the manufacturer of the drill. To disassemble the drill chuck yourself, you need to fulfill three conditions:

have the necessary set of tools available;
have plumbing skills;
to be a person with a stable, balanced psyche.

Possible problems with the chuck when operating a drill: causes, descriptions and ways to solve them

To avoid problems with a drill, you need to be able to operate it correctly. A drill is a universal tool; it can be used to drill wood and metal, plastic and tile, stone and glass, concrete and brick. In everyday life, a rotary impact drill of medium power is usually used. It is equipped with a chuck of the SDS system, which was invented by BOSH. The SDS chuck is not particularly accurate, but is ideal for drilling concrete, stone, and brick. That is, those building materials, where drilling is necessary with impact.

For more precise drilling of metal and wood parts, it has a special adapter for attaching a jaw key chuck or a keyless chuck. A drill cannot be used for milling work. The drill chuck is not designed for side loads and will quickly fail. Of great importance is:

correct choice of drill;
correct sharpening of the cutting part of the drill;
mandatory marking of the center of the holes using a core.

You need to skillfully select the desired speed, feed, operating mode depending on the workpiece material. All these factors directly affect the reliable operation of the drill chuck.

The part falls off

Does the cartridge fly off? This problem occurs quite often even on new drills with a cone-shaped jaw chuck when drilling a deep hole. You need to lift the drill to free it from the chips, and at this moment the chuck flies off the cone. The situation can be corrected by increasing the tension in the cone joint. To do this, the cartridge is heated in oil or oven to a temperature of 110 degrees and placed on a cold drill mandrel.

Clamping jaws jammed

Drill work always takes place in dirty conditions. This is dust, dirt, shavings, sawdust and other small debris. If this debris gets inside the chuck, it can cause jamming. threaded connections, in particular, at the cams. There is only one way out here. Requires disassembly of the cartridge, cleaning and rinsing of moving parts. Before assembly, all moving parts are lubricated with lithol. Especially a lot of waste is poured into the chuck when drilling ceiling surfaces. Here you can think about protecting the cartridge with half a small rubber ball.

Runout

Chuck runout can be caused by various reasons. For example, the Morse seat cone is worn out. This can be checked using paint. An even layer is applied to the cone and the cartridge is inserted. Then the mark he left on the cone is removed and studied. Another reason could be uneven wear on the cams. In this case, they need to be changed. But more often they replace a broken cartridge with a new clamping device.

In the right hands, a household drill can work wonders. With its help, holes are drilled in durable and soft materials. The chuck is an important component of a drilling machine. It is this that ensures the reliability of drill fastening and drilling accuracy. Therefore, it is very important for a home craftsman to be able to independently carry out minor repairs and replacement of this part of the device.

During construction and repair work, a drill is often used. When working intensively with this tool, the bit or drill often becomes loose or falls out. In most cases, the situation can be corrected by tightening the cartridge. If this does not solve the problem and the drill continues to fall out, the drill chuck needs to be replaced or repaired.

Types of cartridge

One of the main parts found in the design of a drill, hammer drill or screwdriver is the chuck. The drill, bit and other working devices are mounted in it between several parts called cams. Based on the design of the cam mechanism, the drill chuck can be a quick-release chuck or a key chuck. In the first type, the drill is fixed manually after applying a little force.

The key mechanism requires the use of a special key. In the body of such a cartridge there is:

Collet. Hardened cylindrical bushing with a cavity inside.
Adjustment clip. It is attached to the outside of the collet and can rotate.

On one edge of the sleeve there are steel petals that allow you to install a drill, reamer, or tap. The rotating holder makes them move along the guides. Depending on the direction of movement, the petals either come closer or move away from each other, clamping or releasing the device installed in them. To ensure the most rigid fixation of the drill, a special key or coupling is used.

Reasons for replacement

The main function of the clamping mechanism is to ensure maximum precision in the hole drilling process. As the drill is used, the seats and steel jaws wear out. The following signs indicate this:

The cartridge flies off the shaft.
The axis of rotation shifts during drilling.
The drill does not lock or cannot be removed.

Each of these situations is unsafe, so if it occurs, you should stop working with the drill and repair or change the chuck.

The drill has a special threaded short-pitch fastening that holds clamping mechanism. In addition to it is a screw with a left-hand thread, located at the outer end of the shaft and acting as a control clamp. To securely fasten parts when assembling drills in production, all connections are treated with a sealing compound, which serves as an adhesive layer and protects the metal from corrosion and oxidation after exposure to moisture. This must be taken into account before disassembling the drill chuck.

Do-it-yourself dismantling

To repair or replace a part, it must be correctly removed from the structure. To do this, you will need to move the cam clamps apart (as far as possible) and unscrew the main fastening screw. Due to the action of centrifugal force or due to the lack of sealant on the thread, it can be very securely fixed in the mounting hole, so great effort will be required during the dismantling process.

This screw has a Phillips-shaped slot, so disassembly is best done using a similar type of screwdriver. Using a mechanical impact screwdriver may break the slots. In this case, additional replacement of the gearbox shaft will be required. To remove the chuck from the thread, you need to prevent the shaft from rotating. To do this, the shaft should be kept stationary while twisting. using an adjustable wrench.

Another method of securing is to manually hold the gears from turning. To do this, you will first need to remove the gearbox housing. If the chuck is of a key type, then to stabilize the shaft it will be enough to insert the key into the hole and set it motionless.

Some drill models use a Morse taper rather than a thread for connection. In this case, after unscrewing the mounting screw, you will need to position the drill vertically using a vice so that the chuck is at the bottom. Then knock it out of the mounting hole using a rubber or wooden mallet. In this case, be sure to use an open-end wrench as a gasket. You should hit it carefully to avoid damaging the body and main parts of the drill.

Mechanism repair

Once the clamping part is removed from the drill, it is necessary to determine whether it can be repaired. If molded plastic and rolled metal were used for its manufacture, its disassembly will lead to a violation of the basic properties of the materials and dynamic characteristics. It will be impossible to use such a mechanism in the future. If the cartridge turns out to be collapsible, you can try to repair it yourself. The recovery process will depend on the nature of the problem.

Vibration during drilling or slipping off the axis indicates that the mounting screw has broken. It can occur due to sudden impacts or lateral loads. To solve the problem, you will have to drill out the broken fastener and replace it with a new one.

Another common problem- jamming of the clamping jaws - can happen due to the use of drills with a diameter that is too large and does not match the size of the hole in the chuck. Excessive use of lubricant can also lead to this. Dust and debris generated when drilling in large quantities, stick to the lubricant and severely clog the mechanism.

Thorough cleaning of the parts will correct the situation. However, the use of a cleaned cartridge will be possible if the threads inside it are intact. Otherwise, the part will need to be replaced. To avoid clogging of the cam structure in the future, the use of a special protection that fits onto the drill and prevents dust from getting inside will help.

Reassembling the structure after completing the repair should be done in the reverse order. At the same time, you need to pay Special attention how reliably the leading element is fixed in the conical recess of the cartridge. Final fixation can be carried out if their longitudinal axes completely coincide.

The joints between parts must be treated with sealant. You can use the drill after it is completely dry. This will take about 10-12 hours.

If the problem does not disappear during operation of the device, this means that the repair or installation was carried out with errors. To eliminate them, you will have to dismantle the device again.

The most popular tool in the household is an electric drill. IN Lately Electric drills, called rotary hammers, are especially popular.
This tool allows you not only to drill a hole, but also, using attachments, to tighten nuts, self-tapping screws, and screws. An electric drill is a reliable tool and rarely fails. How to troubleshoot electric drills. The main faults in electric drills are divided into mechanical and electrical.

Mechanical problems

Common mechanical failures include failure of the clamping chuck.
How to remove the chuck from a screwdriver and replace it?
Let us immediately note that replacing the chuck on an electric drill, screwdriver, or hammer drill is absolutely the same.
The reason the chuck comes out is most often due to wear on the clamping jaws. This is the most serious malfunction of an electric drill. You cannot do without completely replacing the clamping chuck. The video will show you how to remove the chuck from the drill.

By the way! The given method for replacing the cartridge is suitable for any modern models not only electric drills, but also hammer drills, screwdrivers, since all the above designs provide for just this method of attaching the chuck.

But in Soviet-made drills, the chuck is held on a Morse taper and tightened with a screw. How do you remove the cartridge from the cone? To do this, you can use a bearing puller or knock it down with a hammer.

Attention! When purchasing a new power tool with a chuck, be sure to remove the chuck and thoroughly lubricate all contacting parts and threads.

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1. Procedure for replacing the jaw chuck of an electric drill
To disassemble the electric drill, check that its cable is disconnected from the electrical network.
Using a special wrench, open the chuck jaws to the maximum possible position.
If you look inside the open chuck, you will most often see a screw designed to secure the jaw chuck to the motor shaft.
As a rule, the screw is unscrewed using a Phillips screwdriver.
Remember! The thread of the fixing screw is left-handed, and it is unscrewed by turning the screwdriver clockwise.
Unscrew the screw, insert an L-shaped hex key into the chuck in place of the drill and tighten it.

If the head of the screw is worn out and you cannot unscrew it with a screwdriver, proceed this way.
Take a second drill, insert a drill bit the diameter of the screw head into it and start drilling out the screw. It will all end with the screw coming out when drilling.

Insert the open-end wrench onto the motor shaft at the base of the chuck. There are models in which the gap between the chuck and the body is very small. You'll have to pick up the key or cut it to thickness. A key is required to secure the motor shaft.
Models of earlier releases do not have key slots on the shaft. In this case, you need to disassemble the drill body and remove one cover. Simultaneously clamp the driven gear of the cartridge shaft and the cooling fan and try to unscrew the cartridge with a sharp counterclockwise movement.

But let's return to the option with a key.
Now, placing the drill on a wooden plane and fixing the shaft with a wrench, hit the protruding tail of the hex key counterclockwise with a wooden or rubber hammer.
The cartridge is attached to the shaft via a thread.
Rotate the chuck counterclockwise to remove it from the electric drill.
If you don't have an L-shaped hex key, you can use a drill of a suitable diameter, which is pressed into one of the three holes for the clamp key.

Examine the cartridge. If the jaws completely fail, replace the drill chuck with a new one. Install the new chuck onto the drill by performing all steps in reverse order.
Remember! When installing a new chuck, be sure to lubricate all rubbing parts. This is especially true for threaded connections.

We looked at the case when it is necessary to replace the jaw chuck. But power tools are also produced with quick-release chucks.

Keyless chucks allow you to change the drill in a matter of seconds, without using any additional tools or accessories.
Quick-release chucks are divided into single-clutch and double-clutch chucks.
The design of a single-sleeve chuck is equipped with special mechanism, which blocks the shaft when changing the tool. The replacement operation can be performed with one hand.
With a double-coupling chuck, tool changes are performed with both hands. The first coupling is held with one hand, and the other coupling is twisted with the second hand.
But quick-clamping designs do not securely secure the tool, especially in impact mode. And the use of plastic for their manufacture often leads to cartridge failure.
The jaw chuck is more reliable, and the parts used in it are made only of metal. To secure the tool, you must use a special clamping wrench.

Ways to remove a keyless chuck from a drill or screwdriver

The cartridge is mounted on an axis along the thread and locked with a clamping screw.
The quick-release chuck is removed using the same algorithm as the jaw chuck.
First, unscrew the locking screw clockwise. If there are key flats on the shaft near the chuck, then insert the key into the grooves, hold some lever in the chuck, and try to unscrew the chuck by rotating it counterclockwise.
Installing a new cartridge occurs in the reverse order.

But the cartridge can be repaired
In order to inspect the parts of the chuck, it must be disassembled.
We offer a proven and reliable method for disassembling the chuck of an electric drill.

Take a regular hammer drill, remove the boot from it and insert the adapter. An adapter can be made from a broken impact drill. The adapter is a drill shank with a cut off drilling part.
Place the cartridge on the adapter shaft and press it with a rubber shock absorber or a wooden board.
Before installing the chuck on the adapter, it is necessary to insert the jaws into the chuck until they are completely immersed.

After assembling the structure, turn on the hammer drill in impact mode. After 3...5 seconds the cartridge should sort itself out.
Immediately you need to mark the cams and locations in different colors.
Now you can begin to inspect and troubleshoot the cartridge.
If necessary, the cams can be replaced with new ones. True, you can’t do without additional boring of the cams on a lathe.
The remaining parts can be easily replaced if available.

But there are other mechanical faults
There are cases when the failure of an electric drill is caused by a failure of the gearbox or bad work bearings.

2. Procedure for working with the electric drill gearbox
To get to the gearbox, you need to disassemble the plastic housing of the electric drill.
After removing the housing cover, release the chuck shaft and remove it. A driven gear of larger diameter is attached to the shaft.
A small-diameter spiral-shaped drive gear is attached to the electric motor shaft.
There is a bronze bushing in the gear housing, which most often leads to failure of the drill. Everything happens due to its significant wear and tear.
Check the dimensions of the bushing and order it from a turner. Use bronze as a material, but caprolon can also be used.
When replacing a bushing in a gearbox, be sure to check the bearings, their tightness and filling with lubricant.
If the gear teeth are very worn, they will have to be replaced. Gear teeth wear out when the support sleeve fails.
Most often, the driven gear with a larger diameter wears out. Replacing it is simple, you just need to remove the retaining ring and key.
The old gear must be removed from the chuck axis. You can use a puller, or you can just gently knock it down with a hammer, using wooden supports.

Electrical faults
Now let's try to look at the characteristic faults of the electrical part of the drill.
Most often, the operation of an electric drill is interrupted due to wear on the brushes.

1.Replacing brushes in an electric drill
To replace the brushes, you need to remove the side cover of the electric drill housing by unscrewing the fastening screws. There must be at least 7 of them.
The housing is removed by carefully prying up its edges with a screwdriver.
Having opened access to the electric motor, you will see two boxes in which the brushes are installed.
In order to get the brushes, you need to release the boxes, bend the holders and remove the worn brush. Do the same with the second brush.
Install new brushes in the vacant areas and wipe the area around the contact area with a clean cloth soaked in white spirit.

2. Repairing the power cord of an electric drill
One of the unpleasant malfunctions is the periodic stopping of the electric drill during operation. Most often this happens due to an arbitrary loss of power supply. The whole point is that when entering the drill body, the power cable experiences various loads, which lead to wire breakage.

To fix the problem, you need to remove one of the side covers of the case. Use a tester to check the integrity of the cable.
If damage is detected at the point where the cable enters the housing, but the failed piece is cut off from the cable, a 20 cm piece of rigid vinyl chloride tube is put on the cable and the cable is installed in place and then connected.

To replace the button with the speed controller, simply remove the housing cover and disconnect the wires from the controller. The new regulator is installed in the same place and connected according to the diagram. If there is no diagram, then before removing the old regulator, you need to sketch out the connection diagram.

3.A spark appeared inside the case
The occurrence of sparking inside the housing is most often caused by an interturn short circuit of the armature windings.
The second reason that causes sparking is the contaminated surface of the collector lamellas.
Interturn closure can only be determined with a special device.
But you can remove dirt from the collector part yourself using fine sandpaper. After cleaning, you must carefully remove dust from the grooves between the contact plates, called lamellas. The best way to do this is with an old hacksaw blade. At the end of the work, the anchor must be checked with a PYA device.

These are, perhaps, the main malfunctions of electric drills of any brand.