When replacement is needed?
Usually, the service life of brushes in household perforators is calculated, according to the manufacturer, for 70. 120 hours of work. But the owner of the hammer drill is unlikely to keep track of the time the tool has been working. In this regard, it should be noted the convenience of such a function as a brush wear indicator for the Makita perforator. In addition, there is a tool with an automatic shutdown system when the wear is exceeded.
But even if you do not have such a top model, there are signs by which you can determine the increased wear of brushes. These include:
- – increased sparking in the collector area;
- – significant loss of power of the rock drill, the engine does not develop at full speed.
If something like this is observed, it’s time to take a look at the condition of the brushes and the collector.
Note. Usually, for long-term use of the tool, the brushes need to be replaced when their height decreases from the nominal by 1/3 (about 8mm).
If, after removing the brushes from the brush holder, you observe wear, both brushes must be replaced, even if the wear is not uniform. When replacing brushes, it is strongly recommended to clean the collector from graphite dust and carbon deposits. The collector can be cleaned with gasoline (preferably for lighters, its quality is higher) or ethyl alcohol. When replacing the brushes, be sure to rub against the collector. this will reduce the electric arc (sparking), which will have a beneficial effect on both the collector and the engine power. Lapping is done with soft emery paper attached to the manifold. When the anchor rotates, the sandpaper smooths out the unevenness of the new brushes.
Another important nuance when replacing brushes is the degree of hardness of both the brushes and the collector. If you put soft (carbon) brushes on a hard collector, it will quickly wear off. Therefore, it is important to use proprietary brushes from the tool manufacturer for replacement.
How to Replace the Brushes in a Makita Drill
When replacing, you should also pay attention to the brush holder assembly itself. It consists of a profile, a clamping device and a contact group. At the same time, pay attention to the condition of the pressure device spring, if you suspect that it is in good working order and reliability, it is better to replace it with a new one. Fortunately, it is not expensive. For example, if the spring is loose, it will not fit snugly against the manifold, causing increased arcing. And this, in turn, leads to premature wear of the collector plates. And if it jumps off, it will have time to do things in the electric motor for a good repair of the tool.
By the way, if only one brush sparks, the stator may have burned out. It is easy to determine, it is important to have a resistance meter. The stator has two windings, with an average resistance of 4 ohms each. If the resistance of both windings is the same, the stator is intact.
The replacement process itself is not worth describing, it is easy and for most punchers, the design provides for a quick and easy replacement of brushes like a Bosch puncher, or any other, as can be seen in the video at the end of the review. Look for a special window on the case, it is usually closed with a plastic cover.
The hammer drill is an indispensable tool for any kind of repair work. But, like everything under this sun, it is the same not eternal. Sooner or later, you have to deal with its maintenance and repair. And the more attentively you treat it, the longer it will last.
For example, your hammer drill has lost its power. What can this talk about? Is the tool expected to be repaired or is it “its time”? In most cases, it’s okay, most likely. it’s just time to replace the brushes in the hammer drill.
What are brushes and what are they for?
The brush is part of the electric circuit for turning on the electric motor, the current conductor to the armature collector. Since the armature rotates due to the electromagnetic field, there cannot be a fixed connection, as in a stator. A way out of the situation was realized with the help of pieces of graphite, which slides along the collector plates, thereby supplying current to the sectioned armature winding. In turn, a magnetic field is created in the winding of the latter. According to the law of magnetism, the opposite poles are attracted, this creates the movement of the armature. As pictured below.
But we can say that this is the weakest point of collector electric motors, since the brushes are erased during operation, and coal dust clogs the collector. this leads to disruption of the normal operation of the electric motor.
The structure of the brush itself is very simple: a contact terminal, a wire from the terminal to the working surface of the brush and a spring that presses the surface against the collector plate.
We figured out the purpose of the brush, now we will consider their types. There are three types of slip brushes. In fact, there are more of them. but they are not used in rotary hammers. For example, the so-called “generator” (copper. graphite, copper. Carbon) brushes.
In the hammer drill there are brushes of the following types:
- graphite. long service life, but due to the hardness of graphite, “lapping” is not ideal, and the collector suffers from this;
- carbon brushes for a hammer drill. good contact with the working surface of the collector, but short service life;
- carbon. graphite brushes as an alternative to the previous two types.
Carbon brushes for Bosch rotary hammer
Replacing brushes: do it yourself or at a service center?
The easiest option is to refer it to the specialists in the service center, such as replacing the brushes of the Hitachi perforator, but not the cheapest.
Advantages of replacing in a service center:
- – quality, if in an authorized SC;
- – original brushes, also if the center is authorized;
- – preservation of the guarantee for the instrument, if its term has not expired;
- – as a rule, a complete inspection of all “vital” components of the tool is carried out with cleaning and lubrication.
There are also disadvantages: you will have to wait and if it is not guaranteed work. pay. over, the service is not always close.
There is another way. with your own hand. For example, replacing the brushes of a Skil rotary hammer is not difficult, but.
Note. “Attempts to repair the instrument yourself, outside of an authorized service center. Unconditional signs, which include: torn off warranty seals, creases on the slotted parts of the fastening screws, body parts, etc. ” excerpt from the instructions for the punch.
Makita Hammer Drill Repair – How to Replace the Carbon Brush Set
If the instrument is under warranty, it is better to take it to the service. You can do everything right, but who can guarantee that nothing will fail in the hammer drill? And you will have to repair it for your hard-earned money. But, this is just a warning, in order not to open the tool before the end of the warranty period, usually in high-quality models with moderate use, brushes require replacement after the expiration date.
What are the advantages of replacing with your own hands:
- – speed, tool at hand and ready to go;
- – cheaper, you save on the services of craftsmen;
- – You do not expect the instrument to break, its condition is always under control, you just need to look inside;
- – increasing the level of skill, including the maintenance of power tools.
The disadvantages, perhaps, include the following:
- – there are no guarantees of the work performed;
- – there may be a problem with original spare parts;
- – fear of spoiling something, and this is the loss of nerve cells.
In fact, changing brushes is an easy and quick procedure, moreover, as a rule, brushes for a perforator are included with the tool.
How is the replacement done?
Below is a simple algorithm that must be followed when replacing graphite or carbon brushes in a washing machine engine.
- Before starting work, make sure that the machine is turned off and the plug is not plugged into the socket;
- Next, you need to remove the back panel to remove the motor from the case. This is done very simply with just one tool that can unscrew the screws. It can be either a screwdriver or a screwdriver;
- When the panel is removed, you can immediately see the engine, but before getting to it, you need to remove the drive belt, which is located between the drum and the motor;
- The next step is to disconnect the motor connector and ground connector, and then remove the two bolts that act as the motor to the drum. Sometimes it can be very difficult to pull the engine out by yourself. In some cases, a flat screwdriver can help, with which you can pry the motor, thereby making it easier to remove. After removing the engine from the pins, you can put it on the bottom of the machine, then tilt it a little, thereby allowing the engine to easily come out of the case;
- On the engine itself, there are usually two carbon or graphite brushes. If the engine brushes are burnt out, the manifold will be black. In this situation, replacing the brushes is extremely necessary, since they are all worn out and remain on the collector;
- To remove old brushes, you need to unscrew the two bolts that are directly above them. As a rule, after removing it will be possible to see only the remains of carbon brushes. a small piece of graphite or coal;
Before purchasing one or another set of spare parts, you need to pay attention to the manufacturer and the quality of the material from which they are made. You also need to be very careful about the installation, since the duration of the service life directly depends on this.
Photo report. do-it-yourself do-it-yourself replacement of the Sparky BPR 241CE perforator brushes.
After five years of impeccable service, my Sparky began to glitch.
Do-it-yourself Makita 2450 punch repair instruction
Hammer drills are hammer drilling devices designed for drilling and chiselling holes in extra strong materials.
The hammer drill implements two ideas: the working tool rotates and simultaneously moves in the longitudinal direction, creating an impact impulse.
Makita Rotary Hammer Reverse Switch Repair
To repair the reverse switch, the rear cover must be detached. Disconnect the wires carefully from the button. Inspect the switch carefully.
Further disassembly consists in removing the brush holder, having previously released the brushes themselves.
After removing the brush holder, you will reach the contacts of the reverse switch.
Determine its condition, replace contacts if necessary.
Another common electrical fault is poor contact between the stator and the lower contacts of the reversing switch.
We will repair together. Makita HR 2450. Start.
The device consists of an LED or a flashlight bulb, a penlight battery and two pieces of wire. The entire electrical circuit of the control device is a series-connected parts. Connect the battery to one end of the LED or light bulb, and connect the wires to the free ends of the LED and battery. You will have a universal device for checking the continuity of electrical circuits.
Typical malfunctions of the Makita 2450 and 2470 perforator
Frequent faults in the electrical part of the Makita 2450 and Makita 2470 rotary hammer:
- break of the supply cable at the point of entry into the perforator;
- failure of the button of the TG813TLB-1 switch, art. 650508-0, pos. 68.;
- wear of electric carbon brushes SV-419, art.191962-4, pos.65;
- wear of the reverse switch contacts;
- wear of the rotor bearings: bearing 609LLU, art.210060-6, item 51; bearing 607LLU, item 211021-9, item 56;
- short circuit of the rotor 220-240 V, art.515668-8, pos. 54;
- failure of the stator winding 220-240 V for HR2450, item 633488-5, item 59.
The switch TG813TLB-1, art.650508-0 is used as a start button; pos. 68.
Replacement of brushes is carried out when they are completely abraded or poor contact. This malfunction is detected by strong heating of the points of the places where the electric brushes are installed.
Failure to turn on the hammer drill may be caused by abrasion of the contacts on the reverse switch.
Eliminating such a malfunction is very simple.
Rock drills always work in extreme conditions.
The duration of the hammer drill depends not only on the correct operating conditions, but also on the reliability of the parts included in the product.
But no matter how hard you try, over time, punches start to fail.
To properly repair a punch, you need to familiarize yourself with its device.
Do-it-yourself repair of the Makita 2470 and 2450 perforator can be done by a person who has the skills of a locksmith and knows the basics of electrical engineering.
Remember! Observe safety rules and unplug the punch from the mains when disassembling.
Hammer drills Makita 2450 and 2470 are assembled in almost the same way and from the same parts. Repairing them is no different.
For the convenience of repair, below is an assembly diagram and a catalog of parts for Makita punchers.
The scheme of the Makita 2450 and 2470 puncher consists of a mechanical and an electrical part.
The mechanical part provides the transmission of torque to the drill bit, while simultaneously creating a translational movement that creates an impact.
The mechanical part consists of a rotation drive and an impact mechanism.
The electrical circuit of the Makita perforator provides the conversion of electrical energy into kinetic energy through the rotation of the rotor. The electrical part includes an electric motor, a power button with a speed controller, a reverse switch, connecting wires.
The main malfunctions of the punch makita
Rotary hammer malfunctions are divided into electrical and mechanical.
In this article, we will consider all the malfunctions of the electrical part of the Makita 2470 and 2450 rock drills and how to fix them:
Electrical malfunctions of Makita 2450 and Makita 2470 perforators
Electrical faults are manifested in the fact that when the hammer drill is connected to the mains voltage, the tool does not turn on.
The scheme for connecting the Makita puncher to the network is simple.
The electrical diagram of the Makita 2450 perforator is a serial connection of the electric motor, start button and wires.
The scheme of the punch makita 2470 is similar.
Through the connecting cord pos. 72, the supply voltage of 220 V is supplied through the switch pos. 68 and the electric brushes through the brush holder pos. 66 on the rotor lamellas of the electric motor, pos. 54. and through the contacts of the reverse switch, pos. 60, to the stator winding, pos. 59.
The most common malfunction is the lack of contacts in the connections.
Repair of the contact between the stator and the reversing switch
To remove the stator, it is necessary to disconnect the gear housing (black) from the stator housing (green).
Remember! In the mechanical part of the rotor, the bearing is pressed by a special ring. When disassembling, do not lose it.
The stator is located in the green housing. Looking into the middle, you will see two self-tapping screws 4 × 60, ref. 266334-3, item 57, securing the stator to the housing. Unscrew them, remove the plastic stator protection for HR2450, art.419201-3, pos.58., Release the stator.
When you take out the stator, you will see the contacts on the stator and the reversing switch panel.
Clean the contacts thoroughly with sandpaper, treat with solvent or alcohol.
Before assembly, bend the contacts so that they fit snugly into each other. Lubricate the contacts with a thin layer of technical vaseline.
The electrical part of the rock drill is assembled in the reverse order.
It often happens that the machine stops turning the drum. Brush wear may be one of the reasons. This article will tell you how to change the brushes for electric motors of washing machines with your own hands. If the automation works normally and at the same time fills in water properly, but the drum does not work properly or rotates very weakly and emits extraneous sounds, then in this case, you can be one hundred percent sure that the problem lies in the wear of the carbon brushes. Also, an error code may appear on the display, which indicates that the engine is not working properly, as well as the need for an electric brush.
All you need to replace is a Phillips screwdriver and a set of new brushes. It should be noted that it is best to use the original kit for installation, as these brushes will work well without damaging the motor or other parts. In addition, they do not have to be sharpened or filed to fit the size of a particular engine. By themselves, carbon or graphite brushes can simply wear out or delaminate.
Procedure for determining electrical faults
Disease Makita HR 2470 \ The hammer drill 2470 stopped turning on \ The contacts are burnt \ maintenance tool
Determination of the integrity of the electrical part of the Makita perforator. In order to repair the Makita 2450 or Makita 2470 hammer drill with your own hands, you need to arm yourself with devices and tools. Any tester, screwdriver set, wrenches, hammer, wooden guide will do. It’s good to have a screwdriver with a built-in phase indicator.
You need to take a tester, connect to the ends of the punch plug and press the punch switch. If the tester shows some resistance, then the power circuit of the puncher is intact.
If the tester shows infinity, then the continuity of the circuit is broken and you need to remove the back cover to check the connecting cable and electric brushes of the hammer drill.
The back cover (usually black) of the punch is easy to remove, you just need to unscrew three screws with a screwdriver or screwdriver.
Remove the cover and use a screwdriver to disconnect the ends of the wires from the electric brushes.
Using a tester or a home-made device, popularly called “arkashka”, determine the integrity of the lead wires and the correct operation of the switch.
A few words about a simple control device called “arkashka”.
How to correctly determine the malfunction of the rotor rotor of the Makita perforator and choose the brushes
If the carbon brushes are delaminated, this indicates that they were of poor quality. Therefore, before you buy one or another model of brushes, you need to make sure of their worthy quality. Otherwise, it will be necessary to acquire new ones soon, since the duration of their service will be short.
Causes of breakdowns
There may be several reasons why the device fails. The following are considered the main ones:
- Ingress of dirt, moisture, dust.
- Hardening of the grease that is inside the device and helps easier operation.
- Long-term use, use in harsh conditions.
- Constantly switching modes from one to another.
It is also worth paying attention to increased noises during operation. such a phenomenon is often a warning about the presence of problems in the operation of the device.
Features of the repair of the HR2540 model
Rotary hammer model HR 2540 (like hr ft 2470, models hr c, 2610) is the most popular, therefore it is often bought and used for work.
It is not difficult to disassemble and assemble it. The main feature in such a case is the exact observance of the instructions. The purpose of the procedure is to replace unusable parts with new ones in order to ensure the operability of the device.
The disassembly process is simple, it is important to follow the entire sequence step by step, so that later you can correctly return everything to its place:
- Remove the quick-release valve.
- Unscrew the screws connecting the gearbox body of the mechanical section.
- Remove the black cover by first pushing the front of the shaft.
- To remove the mechanical part from the green side. to do this, first unscrew the three connecting screws that hold the cover. Then remove the cover, remove the carbon brushes and release the brush holder springs.
- After the mechanical block is released, it is required to disconnect the rotor from it, which is fixed in it and is pulled out with a slight wiggle.
When this process is completed, continue the analysis of the mechanical block of the impact unit: you need to remove a couple of bolts located in the case. Then the intermediate shaft must be disassembled. To do this, the following parts are sequentially pulled out according to the scheme:
- ring, bearing,
- straight-toothed gear,
- friction bearing,
- flat washer,
- bearing 606,
- retaining ring S-707,
- compression spiral,
The next step is to disassemble the shaft of the slotted barrel, which is pulled out of the body, and the cylinder is taken out of it. The next step is to remove the piston connector, flat washers, and striker. If desired, you can disassemble the shaft itself, the process is also recommended to be carried out sequentially, carefully placing all the parts on the table.
After that, the electrical part is disassembled, in which the stator, switch, rotor, carbon brushes and the holder for them are removed.
Important! Before disassembling the Makita hr 24 50 perforator, experts recommend preparing an additional tool that may be required during the procedure.
Before parsing, it is recommended to carefully examine the product
How to change the cartridge
Changing the cartridge will not take long. Experts recommend trying to fix it initially. If this option is not possible, then it is worth replacing the part as follows:
- A cartridge is screwed onto the device.
- Place a screw in the socket.
- Carefully tighten everything with a screwdriver.
The procedure is carried out strictly in a certain sequence.
Instrument disassembly and assembly procedure
How to disassemble a Makita rotary hammer at home? It is possible to assemble and disassemble the device yourself.
If the location of the brushes is very hot, then most likely this part needs to be replaced. It is recommended to first check the condition of the elements: replacement is carried out if they are completely worn out. The procedure will require a high-quality electrical screwdriver.
Disassembly of the device is carried out according to the described instructions, after which new parts are placed in place of the old brushes.
Attention! Some models differ in the clamping mechanism, so before replacing it will have to be removed.
All parts are recommended to be treated with fresh grease.
The assembly of the device takes place in the opposite order, strictly according to the list. It is preliminarily recommended to apply fresh lubricant to all parts, clean the housing with gasoline. If necessary, replace all damaged parts with new ones.
The hammer drill differs from a conventional drill in that it has a greater impact force. The device is used when working with serious materials. Due to the high power of the device, a person spends less effort, but the result is better.
The design of the Makita perforator consists of two parts. electrical and mechanized. They are easy to distinguish by color. the first is green, the second is black.
Pistol-type rock drills
The device of the percussion mechanism of the pistol-type unit is slightly different from the mechanism of the same purpose installed in the barrel-type apparatus.
Its main difference is that the piston does not move with the help of a connecting rod, but from a swinging (“drunk”) bearing. Therefore, the most common failure of this unit is the wear of a “drunken” bearing that needs to be replaced.
The next photo shows a broken “drunken” bearing, which is the reason that the hammer has stopped hammering.
The swinging bearing is removed using a flat screwdriver, with which you need to pick up the bracket and remove it. After that, the bearing is easily separated from the gear housing.
When replacing a collapsed bearing, rinse the gearbox well, since it is in its housing that fragments of a broken part can remain.
After cleaning and installing a new bearing, apply a grease layer of grease to this block.
Also, the reason that the device does not hit may be a broken firing pin. To get it, you need to remove the retaining ring, which is visible in the hole.
Take a small screwdriver, hook the ring with it, and slide it to the right (towards the gear).
Do the same on the other side of the part. Next, insert a screwdriver into the hole of the part and push the removed inner parts of the mechanism.
After this action, you can easily get the retaining ring, and the body, which contains the broken striker.
If you disassemble this case, then you will see the “culprit” of the malfunction, due to which the hammer drill does not hammer.
When assembling the striking mechanism, be sure to apply generous grease to all parts.
Dismantling and repairing a punch with your own hands
A hammer drill, like any electric tool, requires careful attitude, correct operation and timely prevention. If you neglect these standards, then the device may fail without depleting its resource. Repair of a hammer drill for some malfunctions can be done by hand, and to eliminate breakdowns associated with the electrical part of the engine, you will need the help of a specialist.
If any mechanical malfunction appears in the punch, then its presence can be determined by ear (noise rises, rattling appears).
You may also feel increased vibration or an unpleasant odor coming from the unit’s casing.
So, the following can be attributed to mechanical failures:
- breakage of the device operating mode switch;
- worn out rubber bands of the striker and striker;
- failure of the striking mechanism;
- failure of the unit barrel due to wear;
- breakage of gear teeth;
- breakage of the chuck causing the drill to fly out.
Punch disassembly algorithm
To eliminate mechanical and electrical faults (with the exception of a breakdown of the electrical plug), you cannot do without disassembling the unit body. The most popular among craftsmen, both home and professional, are the brands of perforators Bosch, Makita, Interskol, Energomash. The design of units from different manufacturers is approximately the same, therefore, the methods for disassembling the devices will be similar. But you should not disassemble the device completely, as it will be difficult to assemble it back. The photo below shows what a fully disassembled punch looks like.
Replacing the brushes of the electric motor
The main sign that it is time to change the brushes is the formation of increased sparking in the area of the electric motor collector, the rapid heating of the brush holders, and the smell of burning. When the brushes are not worn out, the spark can only be seen under them. Otherwise, the spark is visible all over the collector circle.
How to Replace Makita Cordless Drill Brushes – DIY Survival Skills
The presence of a spark in the circle of the collector with worn brushes is a sign of bearing wear, a violation of the rotor or stator insulation, burnout of the collector plates, burnout of the stator or rotor.
Another sign that the stator has burned out is the presence of sparks under only one electrode. If you have a tester, you can use it to check the stator and the rotor: measure the resistance on the rotor and stator alternately. If it is the same on both windings, then everything is in order with the stator. If you notice clear signs of problems with the rotor or stator with your rock drill, you will have to take the device to a service center for repair. As for the brushes, you can change them yourself.
To get to the place where the brushes are installed, you will need to disassemble the housing in which the motor is installed, or simply remove the back cover. Opening the lid, you will see the brushes fixed in special holders. The photo below shows how these parts look.
There are 3 types of brushes that are installed on rotary hammer motors.
- Graphite. they are distinguished by their durability, but since they are very hard, then grinding them to the collector is not ideal, which negatively affects the latter.
- Coal. easily rub against the manifold, providing good contact, but wear quickly.
- Carbon-graphite is an ideal option, since they are a mixture of 2 components that complement each other.
It is very important not to wait for the engine to sparkle and then change the brushes. Replacement is needed after they are worn out by 1/3 of the nominal (8 mm). Even if one brush has worn less than the other, you still need to change both.
Pay attention to the condition of the spring in new brushes and the attachment of the contact. If the spring goes off while the engine is running, it will be severely damaged. Also, if the spring is weak, then it will not be able to provide good contact.
Before changing the brushes, it is imperative to thoroughly clean the rotor and stator from the remains of graphite or coal dust. You can clean these parts with technical or medical alcohol.
Next, you should fix the electrodes in the holders and grind them to the collector. To do this, put a piece of fine-grain sandpaper on the collector and use a rotating motion in different directions to grind the electrode. Lapping continues until the electrode contact area is slightly rounded. This will provide a better fit to the collector plates and, accordingly, better contact.
Slant Tooth Gears
The reason that the device stopped working normally, namely, stopped drilling and chiseling, may lie in worn teeth on the rotor shaft.
If this happens, the teeth will also be worn out on the intermediate helical gear.
This problem occurs when the tool is jammed or the clutch is not working properly. Breakage is eliminated by replacing the intermediate gear and the engine rotor.
Diagram of the percussion mechanism, its malfunctions and repair
The impact mechanisms of perforators differ in their design, depending on which family the devices belong to. Therefore, the repair of these mechanisms will take place according to different principles.
Other mechanical failures and their elimination
In addition to breakdowns associated with the percussion mechanism, other mechanical breakdowns may occur in the hammer drill.