Dismantling the rotary hammer Bosch 2 28

Disassembling the cylinder

A striker, pos. 27, is inserted inside the cylinder, from which it is necessary to remove the rubber ring, pos. 73. For any disassembly, rubber parts must be replaced without fail.

At the opposite end of the cylinder, a hinge, pos. 29, and two flat washers, pos. 41, are inserted.

Punch repair yourself step by step

To repair a device such as a hammer drill, you should be as prepared as possible, which will reduce financial and labor costs to a minimum. It’s not bad if you are more or less familiar with the construction of a punch, you know what parts and assemblies it consists of, which will allow you to quickly replace a broken part. comes down to a banal replacement of the “flying” elements, which include:

  • Anchor;
  • Brushes;
  • Gears;
  • Starters;
  • Bearings;
  • Network cables;
  • Switches.

Do-it-yourself bosch punch repair

A hammer drill is a construction tool with which slotting and drilling operations are performed. Thanks to a special mechanism, the hammer drill is very effective and quickly punches a hole in different materials. It can be used in work with concrete, brick, metal, wood, stone. Bosch drills are very common among builders and ordinary people, so it is very important to know how these devices are repaired in the event of a breakdown.

Bosch Hammer Drill Repair / Bosch GBH 2-26 DFR

It is important to pay attention to the original models! There is a fake Bosch Hammer Drill 32 hammer drill. Beware of fakes!

Dismantling the quick release chuck

Two types of chuck are most commonly used in Bosch rock drills: SDS-plus chucks and SDS-max chucks. The difference between them in the principle of clamping the tail of the working organ.

The device of the Bosch hammer drill chuck differs in the design of the tool landing rods, depending on the SDS-plus or SDS-max model. In addition to the listed types of cartridges, there are SDS-top, SDS-quick cartridges.

dismantling, rotary, hammer, bosch

The difference between the attachment points of the cartridges

The procedure for disassembling the chuck of the Bosch 2-26 hammer drill is simple:

  • remove the rubber tip, pos. 34;
  • take out the retaining ring, pos. 87;
  • remove the steel washer pos. 833;
  • remove the conical spring, pos. 833;
  • carefully, so as not to lose, using a magnet, remove the barrel balls pos. 89.

SDS-plus chuck

Carefully inspect all parts of the cartridge.

Disassembled SDS-plus quick release chuck

SDS-plus chucks have been specially developed for drilling tools. The diameter of the tool shanks is 10 mm, the length of the working tool is in the range of 110. 1000 mm. The diameter of the drills is in the range of 4. 26 mm.

Step by step disassemble the puncher. quick search for breakage

Disassembly of the percussion barrel assembly

  • disassembly of the Bosch perforator barrel assembly begins from the side of the cavity, taking out the cylinder poz.26 with the hammer poz.27;
  • the firing pin assembly must be removed from the cavity;
  • from the side of the chuck shaft, remove the retaining ring, pos. 85, the steel ring, pos. 38, and one more retaining ring, pos. 85;
  • remove the spur gear pos. 22.

Impact mechanism assembly, countershaft and drunken bearing

Repair of rotary hammers Bosch 2 26

Before you fix something in this model, you need to familiarize yourself with the features of the device, the scheme and the principle of operation. The rotor shaft transmits rotation to the barrel shaft through an intermediate shaft, the bearing of which directs the return movement to the impact piston.

When disassembling the barrel shaft in the shock unit, you need to pay special attention to fixing the spur gear. Before removing it, you need to remove 3 pins, on which it is fixed in this model.

Dismantling the punch and removing the cartridge

To repair a hammer drill, you first need to disassemble it correctly. And we begin to do this by disassembling the cartridge.

  • Remove the rubber tip and retaining ring;
  • We remove the washer and the conical spring;
  • We take out the side balls (preferably with a magnet);
  • We put the lever of the operating modes in the position equivalent to the maximum, and remove the switch knob. We fix the position;
  • Remove the rear cover for the handle and engine brush;
  • Unscrew 4 screws near the drill to remove the front cover;
  • We take out the barrel and the shaft, and with the help of a screwdriver. the bracket and the bearing;
  • Open the back cover and take out the reverse switch;
  • We remove the rotor, for which we unscrew the crepes and disconnect the terminals from the starter, which also needs to be removed by removing the protective casing.

Important! When disassembling, be extremely careful about where and when you remove certain parts. Fold them up so as not to lose. It depends on whether you fold the instrument back or not.

What can break?

They can burst from metal fatigue or due to manufacturing defects. You can find a replacement in the automotive market or make your own ring. To do this, you need steel wire, a pipe of the appropriate diameter, a vice, pliers.

This usually happens if, when changing the tip, they “forget” to lubricate it. The largest diameter of the worn specimen is measured and the appropriate size is selected. For example. from an old bearing.

The balls must be exactly the same size, otherwise the tip will either fall out during operation or have no free play.

If the inner cylinder is worn out, or the chuck body has mechanical damage, the entire assembly must be replaced. It is impossible to restore it. When installing a new cartridge, remove the spring and balls from the old ring. They can come in handy for subsequent repairs.

After repair (replacement) and installation of the cartridge in place. work for a while without heavy loads. Then check the operability of the mechanism, the reliability of the fastening and the absence of backlash.

In conclusion, see the do-it-yourself punch repair. When starting a repair, you need to know exactly how to disassemble a punch, this video contains all the stages of disassembly and illustrative examples of replacing broken tool assemblies. But be very careful when disassembling, if this is the first time you are doing this, then it is better to take a photo or video of the sequence of your actions, so that after eliminating the cause of the breakdown, you can easily assemble your puncher back.

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.

Self-repair punch

In addition to electrical faults, such as a burned-out winding of the motor, the erasure of the brushes on it, or the failure of the switch, mechanical breakdowns can occur in the hammer drill.

The piston shock group (especially in the crank-connecting rod design) rarely breaks down, but the main element of the load transmission. the cartridge, can suddenly fail.

This is most often due to untimely lubrication when changing the working tip. Natural wear and tear is also possible under intense loads.

First of all, let’s figure out how to remove the cartridge. You can repair it without removing it, but it is not so convenient. The chuck is mounted on a spindle or screw rod. For work you will need: a hammer, a strong screwdriver, pliers with long jaws and an open-end wrench. A table vise will greatly facilitate the process if the fastening is too tight.

Remove the retaining ring from the cartridge

First, the cartridge must be disassembled. precisely, dismantle the outer part of the mechanism. Remove the protective rubber sleeve at the end and the first retaining ring.

Then we move the working sleeve with a movement, as for changing the tip, and remove the second retaining ring. The rings are opened with a heavy-duty screwdriver; a car snap ring puller will not work here. The force is great, so try to avoid injury.

We disassemble the quick-release mechanism of the chuck

Bosch Hammer Drill Refreshment | Bosch GBH 2-24 DSR disassemble

Next, you need to disassemble the SDS mechanism. We remove the spring and fixing balls. To remove the chuck, the spindle must be secured. Or vice versa. clamp the disassembled chuck in a vice, and rotate the spindle with an open-end wrench by the flats. If there are none on the shaft, you will have to disassemble the punch body and find a way to clamp the spindle in a vice. Then you need to rotate the cartridge itself.

From constant shock and torsional loads, the threads can sit very tightly. Soaking with WD-40 will not work. It is necessary to apply a light but sharp blow to the chuck body to relieve stress, then the threaded connection will loosen.

The cartridge should be removed not only for repair, but also for prophylaxis, cleaning, lubrication. It is recommended to do this after the end of the working season, before preserving the tool.

All parts must be washed in a penetrating liquid such as kerosene. Check the wear of the locking balls, if necessary replace them with new ones. Inspect springs for chipping and deformation.

Then all parts are greased and assembled in reverse order. If it is only necessary to lubricate the SDS mechanism, it is not necessary to remove the cartridge. It is enough just to disassemble it directly on the rotary hammer shaft.

Having mastered the removal procedure, you can easily change the cartridge for another. This may be necessary in the event of its final breakdown, or switching to a different type of handpieces.

As a handy tip: If you do not work on an occasional basis, but on a regular basis, keep a spare cartridge of the same type close at hand.

This will allow you not to interrupt critical work in the event of a breakdown. You just make a replacement and continue the process, postponing the repair for a more favorable time.

Other mechanical failures and their elimination

In addition to breakdowns associated with the percussion mechanism, other mechanical breakdowns may occur in the hammer drill.

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.

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.

We disassemble the case

If disassembly of the unit body is required, then first you need to remove the operating mode switch.

  • Place the switch in the “Shock” position. Usually a hammer is drawn in this place on the body. If this mode is not available, put the switch in the position “Impact drilling”.
  • Next, you should press the button located on the switch handle and turn it slightly below the hammer icon until it clicks.
  • After that, you need to pry the switch with a screwdriver and, pulling it towards you, remove it. In some models of units, this switch can be screwed to the body.

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.

Repair of rotary hammers Bosch 2 26

Before you fix something in this model, you need to familiarize yourself with the features of the device, the scheme and the principle of operation. The rotor shaft transmits rotation to the barrel shaft through an intermediate shaft, the bearing of which directs the return movement to the impact piston.

When disassembling the barrel shaft in the shock unit, you need to pay special attention to fixing the spur gear. Before removing it, you need to remove 3 pins, on which it is fixed in this model.

Repair of rotary hammers Bosch 2 24

In this bosch gbh 2 24 dsr rock drill, the intermediate shaft consists of a shift part, a bearing assembly and a clutch. The latter deteriorates most often, because the teeth in it wear out quickly. Repair of this breakdown consists in correcting the profile of the teeth of the engagement. You will often notice that there is no hit. The hammer drill may gradually stop hammering due to the wear of the rubber parts, which must be replaced in time. And if you use more than necessary force, this can lead to the fact that the firing pin is jammed in the impact piston.

Repair of Bosch rotary hammers and its features

A hammer drill is a construction tool with which slotting and drilling operations are performed. Thanks to a special mechanism, the hammer drill is very effective and quickly punches a hole in different materials. It can be used in work with concrete, brick, metal, wood, stone. Bosch drills are very common among builders and ordinary people, so it is very important to know how these devices are repaired in the event of a breakdown.

It is important to pay attention to the original models! There is a fake Bosch Hammer Drill 32 hammer drill. Beware of fakes!

Do-it-yourself Bosch hammer drill repair

If any parts in the tool are damaged, broken or poorly performing their function, then they just need to be replaced. If the brushes are worn out, then when disassembling them, they are simply replaced with new ones. A hammer drill chuck with a slow rotation of the rim, a worn boot, and failed bearings are also replaced. But there are other faults that you can fix. If a winding breakdown occurs, then it is necessary to rewind the stator and the armature. It is necessary to monitor the lubrication and lubricate some parts from time to time.

Repair of rotary hammers Bosch 2 26

Before you fix something in this model, you need to familiarize yourself with the features of the device, the scheme and the principle of operation. The rotor shaft transmits rotation to the barrel shaft through an intermediate shaft, the bearing of which directs the return movement to the impact piston.

When disassembling the barrel shaft in the shock unit, you need to pay special attention to fixing the spur gear. Before removing it, you need to remove 3 pins, on which it is fixed in this model.

Dismantling the punch and removing the cartridge

To repair a hammer drill, you first need to disassemble it correctly. And we begin to do this by disassembling the cartridge.

  • Remove the rubber tip and retaining ring;
  • We remove the washer and the conical spring;
  • We take out the side balls (preferably with a magnet);
  • We put the lever of the operating modes in the position equivalent to the maximum, and remove the switch knob. We fix the position;
  • Remove the rear cover for the handle and engine brush;
  • Unscrew 4 screws near the drill to remove the front cover;
  • We take out the barrel and the shaft, and with the help of a screwdriver. the bracket and the bearing;
  • Open the back cover and take out the reverse switch;
  • We remove the rotor, for which we unscrew the crepes and disconnect the terminals from the starter, which also needs to be removed by removing the protective casing.

Important! When disassembling, be extremely careful about where and when you remove certain parts. Fold them up so as not to lose. It depends on whether you fold the instrument back or not.

Rotary hammer device Bosch

Rotary hammers are of two types:

  • with horizontal installation of the engine (the barrel and the engine armature are placed in parallel);
  • with vertical installation of the engine (the same parts are at right angles).

Electrical and mechanical parts are the main components of this tool.

The electrical part consists of:

  • engine;
  • engine control device (sometimes combined with a switch);
  • on / off switch;
  • elements that suppress interference;
  • power cord.

The mechanical composition is as follows:

  • a gearbox that is attached to the motor shaft;
  • impact mechanism;
  • clutch.

This device may be supplied with various add-ons in the form of a drill, crowns, vacuum cleaner and other parts.

Repair of perforators Bosch 2-28

In this model of the tool, the splines sometimes wear out. In this case, it is necessary to disassemble the gearbox (it is almost similar to Bosch 2-24, only the bearing is different). It is better to replace the entire barrel, because the strikers wear out along with the splines.

As you can see, the repair of punchers can be done at home with your own hands. At the same time, do not spend large sums on various types of repairs in service centers, which, as we know, are very expensive. But do not forget that you must adhere to the rules of use and safety precautions.

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