How to remove a bearing from an angle grinder anchor

Today, home and professional craftsmen use several methods to solve this problem. If it becomes necessary to remove the bearing from the anchor of an angle grinder or other tool, this can be done using the following devices:

  • Strippers. These are special devices that allow you to easily and safely remove bearings of different sizes from the anchor of an angle grinder. The use of pullers practically does not require the use of physical force, even if the bearing is tightly seated. The centering mechanism ensures the simultaneous installation of the device’s grippers. It can be used in any position. Before removing the bearing, you need to clean the armature shaft of the angle grinder from old grease, chips, sand so that nothing interferes with removing the part. The centering mechanism allows the puller to position itself precisely. If the bearing is intact, and the dismantling process is carried out for inspection, it should be pulled out by the inner ring so as not to damage it. For large anchor shafts of an angle grinder, use a massive puller with three or four gripping paws, and for small ones, devices with replaceable plates or strips are suitable.
  • Hammers, chisels, wrenches and other tools at hand. In this case, in order to remove the bearing from the anchor of the angle grinder, it is heated with gas, squeezed in a vice, grinded, chopped and many other operations are performed. These methods, of course, can be effective, but there is a great risk that the seat of the part will be mechanically damaged. And often the bearing itself after such manipulations without a puller will be unsuitable for further use. In addition, the performer may be injured as a result of hitting the face, eyes or head with pieces of the clip, which fly apart after impacts.

As practice shows, pullers are more effective in this situation. They allow you to quickly, easily and without much risk remove the bearing from the armature of the power tool and inspect or replace parts. If you have to periodically carry out such operations, you should acquire such a useful device. The use of improvised devices is permissible only if you have experience in repairing power tools and an urgent replacement of a part is required.

How to Remove Angle Grinder Bearing Without Puller

How to remove a bearing from an armature of a power tool: a few practical tips

Now many home craftsmen, non-professional craftsmen, have a whole arsenal of power tools that help to cope with household non-repair and construction tasks. Perforators, jigsaws, angle grinders, drills. they greatly simplify and do not speed up work. But it happens that the power tool burns out. You should not rush not to send it to the trash because of this. Due to intensive operation, the parts wear out, respectively, the equipment is not capable of operating in normal mode. If you know how to remove a bearing from the anchor of a power tool, it is natural to extend the life of your own “helper”. Timely replacement of non-lubricating parts allows you to operate the device for a longer time.

The main task of the power tool motor. it is rotation. The anchor is the fundamental part of the device that forces the working mechanism to turn. The service life of a part depends on the power, not the speed, in addition to the activity of the equipment implementation. Bearings are needed to reduce the friction during the movement of parts. Specifically, they provide smooth rotation and do not enhance the running mechanism of the power tool. If you look at the bearings at the wrong time to lubricate, their service life increases significantly.

How to remove the bearing from the rotor angle grinder

One of the many ways to remove the bearing from the rotor of an electric tool, without fear of damage

Replacing the collector

Replacing only one collector will not eliminate the malfunction. A fully impregnated armature will damage the windings remaining on the rotor when the collector is removed. It is almost impossible to adapt the new collector to the old winding terminals. Therefore, when replacing the collector, it is better to rewind the new windings at the same time. The most technically simple option (much more expensive) is to completely replace the rotor.

Festool ts 55 ebq how to remove an armature bearing without a puller

small tricks in replacing the bearing on an angle grinder.

If during the disassembly of the electric motor you notice traces of friction of parts, it means that the bearings have worn out. It is necessary to immediately remove the bearing from the armature and replace the spare parts. This will allow you to avoid negative consequences in the form of engine breakdown or complete failure of the tool.

How to remove an anchor from an angle grinder

remove, bearing, angle, grinder

angle grinders successfully solve the problem of processing a large number of types of materials. The difference in the modes of their processing, work in conditions of increased dust formation from abrasive particles contributes to the failure of units and parts of the angle grinder. The rotor, as one of the main elements of the electric drive, fails quite often. The rotor is repaired after complete disassembly of the angle grinder, where it is a separate unit not connected with other elements. Information on how such a disassembly is performed in this article.

Possible electrical faults

Malfunctions of the electrical part of the Bosch angle grinder can be conditionally divided into simple and complex.

Assembling the angle grinder

The assembly of an angle grinder begins with an examination of all parts, assemblies, bearings, gears.

Prepare the workplace in advance with correct and good lighting, place tools, lubricants, napkins.

DIY Bosch angle grinder disassembly

For the owner of a power tool, knowledge of its device and the ability to disassemble is a must.

Knowing how to disassemble the angle grinder allows you to independently perform such work as changing lubricants, changing bearings and carbon brushes.

To detach the gearbox housing pos. 821 from the stator housing pos. 888, it is necessary to disassemble (remove) the housing of the handle of the angle grinder pos. 24.

This operation must be performed in order to get the carbon brushes pos. 810 holding the rotor collector.

At the second stage, unscrew the 4 (four) screws pos. 61, securing the gearbox and stator housings.

Having pulled out the rotor together with the gearbox, proceed to dismantle the gearbox.

Repair of the Bosch angle grinder begins with disassembling the gearbox pos. 821. Disassembly of the gearbox begins with unscrewing 4 (four) screws, pos. 60. As a rule, the screws are screwed into the sealant at the factory. You will have to make some effort.

Let’s note right away! Low-power Bosch grinders use spur gears in the gearbox. For Bulgarians with a power of over 1000 W, helical gears are used in gearboxes.

How to remove the drive gear of a Bosch angle grinder

The drive gear, pos. 27, is removed from the rotor shaft in the following sequence:

  • clamp the rotor by hand and, using an open-end wrench, unscrew the nut pos. 45 counterclockwise.;
  • remove the washer pos. 59.;
  • pull out the leading helical gear pos. 27.

Visually check the integrity of the gear teeth, contact patch.

If the gears are badly worn (licked), there are chipped teeth, then they must be replaced. over, the replacement of gears is always made in pairs.

In low-power Bosch grinders, a needle bearing is used as a support bearing in the gearbox.

Do-it-yourself Bosch angle grinder repair follow the instructions provided strictly. If you need to remove the needle bearing from the housing, you can’t do without quick wits. Its dismantling is performed only upon destruction.

To get a destroyed bearing race, you can use a proven method.

A tap is selected with a diameter slightly larger than the inner diameter of the destroyed needle bearing holder. The tap is fixed in the chuck of an electric screwdriver and screwed carefully at low speeds into the holder. When the tap reaches the bottom of the gear case, it will begin to lift the clip.

In addition to the needle bearing of the spindle shaft, Bosch grinders use two more bearings mounted on the rotor shaft.

Detailed photo report on the replacement of armature bearings of an angle grinder (angle grinder) 1400 W 220V.

The angle grinder got its nickname “angle grinder” back in the days of the Soviet Union. Because, at that time, this instrument was manufactured and supplied from Bulgaria. The angle grinder in the arsenal of household tools is the most versatile and multifunctional assistant. The angle grinder in operation is subjected to strong and uneven loads and long periods of operation, therefore, malfunctions occur more often than with other power tools.

In my angle grinder, when turned on, an extraneous sound and increased vibration appeared. It is more expensive to operate a tool with such characteristics further.

We begin the repair of the angle grinder by unscrewing the four screws of the gearbox cover.

Prying off with a screwdriver, remove the gearbox cover assembly with a secondary shaft and gear. The bearing of the output shaft turned out to be working, without backlash and jamming.

But the front armature bearing. completely crumbled. The bearing balls were in the gear grease and the small gear retaining ring was worn on one side. To replace the front bearing, first of all, unscrew the covers of the armature contact brushes and remove the brushes.

Then we unscrew the four screws securing the angle grinder gearbox to the stator and remove the armature together with the gearbox housing.

To remove and install the armature gear retaining ring, you need to make a simple tool. For this I used old scissors. The ends of the scissors on emery were ground off, as in the photo.

This is the view that turned out to be my retaining ring. For the convenience of mounting the retaining ring when assembling the reducer, the ends of the scissors were heated red-hot with a gas burner and bent at right angles to the plane of the scissors. Then again heated and cooled in engine oil.

After dismantling the armature gear, I removed the armature from the gearbox housing. This is the view of the front armature bearing.

The outer cage of the armature bearing is removed from the gearbox housing by lightly tapping on a metal screwdriver inserted from the inner side of the gearbox housing into the cage groove. It is important not to skew the cage when pressing out.

But the inner bearing race was tightly seated on the armature shaft.

To dismantle it, I used a standard screw holder for threading.

Studs were unscrewed from it for rotation when threading. And the rod holder itself is installed on the bearing race, so that the screws for fixing the rod fit into the groove of the bearing race. Then tighten the screws evenly on each side and thus securely attach the holder to the holder. Now we grab the puller with the paws of the tool holder and remove the clip from the shaft.

This is what the front armature bearing of my angle grinder looked like.

New bearings must be filled with grease. To do this, you need a sharp awl, Litol 24 grease and a mandrel for mounting bearing caps. To lubricate the closed bearing, you need to remove the cover by prying it with an awl, as in the photo.

Now we fill the bearing with grease and put the cover in place.

To put the cap in the bearing without damage, you need to select a mandrel in diameter slightly larger than the outer diameter of the bearing cap. I used a socket wrench head.

The bearings are lubricated. Press the front bearing into the gearbox housing using the outer race of the old bearing and fix it with a flange.

At the anchor, the anchor collector is cleaned with P1000 sandpaper. With a stationery knife, carefully, without much pressure, we clean the tracks between the collector lamellas. And after these operations, we carefully wipe the collector with a cotton napkin moistened with white spirit or other solvent.

Next, it is necessary to press the armature shaft into the inner race of the front bearing. To do this, place the gearbox housing on a wooden surface with the bearing facing up. We insert the armature shaft into the bearing cage from above and lightly tap it through the mandrel, along the rear armature bearing we put the armature in place.

We put a small gear on the armature shaft. If, after installing the gear, the groove for the circlip extends beyond the end of the gear, then the installation is correct. We put the retaining ring in place.

If the groove does not come out due to the end of the gear or is halfway out, the shaft must still be seated in the housing.

After these operations, remove the old rear bearing from the armature shaft and install a new one. We place the armature with the gearbox in the stator and tighten the four screws securing the gearbox. We check the shaft for rotation. The shaft should rotate easily without jamming in the bearings. We put in place the contact brushes and screw their covers. Now we put a special grease for the angle grinder in the gearbox of the angle grinder and put the gearbox cover with the secondary shaft in place.

We tighten the four fastening screws and check the angle grinder by plugging in.

The angle grinder should quickly gain momentum and work without extraneous sounds. At this point, the repair of the angle grinder can be considered complete. Good luck with your work!

If, when turning on the grinder, circular sparking is observed, this is an indication that the anchor lamellae have burnt out and an urgent replacement is required. You will learn how to repair a tool with your own hands from our step-by-step master class using the example of the Makita 9069 angle grinder.

Replacing an anchor in an angle grinder is straightforward. It is not necessary to give the instrument to the workshop, you can do it yourself.

  • flat screwdriver;
  • hex keys;
  • new anchor for angle grinder Makita 9069;
  • rags for cleaning the disc from dust and grease.

Malfunctions of speed regulators

In the Bosch series grinders, especially of low power, speed controllers are installed. Access to the speed controller is carried out by opening the handle of the stator housing held on one end screw.

The speed range of the regulator can be set with a potentiometer hidden in the knob panel.

Removing a faulty regulator is easy enough, since it is attached only to the rail.

The repair of the speed regulator of an angle grinder is a complex process, the implementation of which requires not only special knowledge, but tools and equipment.

If the speed controller is out of order, but there is no new one, then disconnect the supply wires and install a jumper.

A jumper is shown in red, which is installed when the speed regulator fails.

Stator repair

The repair of a Bosch angle grinder also includes the restoration of the stator. The main symptom of a stator failure is a spontaneous increase in the speed of a working angle grinder, which cannot be reduced by adjustments. A burnt-out stator winding changes color and becomes darker. The stator core also darkens from high temperatures.

It is easier to rewind the stator, although certain rules and sequence must be followed here.

If you have removed the stator housing cover, carefully inspect the condition of the carbon brushes and rotor collector fins.

The length of the carbon brushes should not be less than 8 mm. By the way, Bosch grinders use carbon brushes with a “shot”, a device that stops the operation of an angle grinder with a minimum length of a carbon brush.

The collector lamellae must be free of carbon deposits or wear. Carbon deposits are easily removed with cotton wool dipped in alcohol.

How to remove a bearing from an armature of a power tool: a few practical tips

Today, many DIYers and professional craftsmen have a whole arsenal of power tools that help them cope with domestic and repair and construction tasks. Rotary hammers, jigsaws, angle grinders, drills. all of them greatly simplify and speed up work. However, it happens that the power tool breaks down. Do not rush and send it to the trash because of this. Due to intensive use, the parts wear out, and therefore the equipment cannot work in normal mode. If you know how to remove the bearing from the anchor of the power tool, you can extend the life of your “helper”. Timely replacement and lubrication of parts allows you to operate the device for a longer time.

The main task of the motor of the power tool. it is rotation. The anchor is that important part of the device that makes the working mechanism rotate. The service life of the part depends on the power and speed, as well as the activity of the equipment use. Bearings are needed to reduce friction while moving parts. They provide smooth rotation and improve the running mechanism of the power tool. If the bearings are monitored and lubricated in a timely manner, their service life increases several times.

How to remove a bearing from an angle grinder anchor?

Today, home and professional craftsmen use several methods to solve this problem. If it becomes necessary to remove the bearing from the anchor of an angle grinder or other tool, this can be done using the following devices:

  • Strippers. These are special devices that allow you to easily and safely remove bearings of different sizes from the anchor of an angle grinder. The use of pullers practically does not require the use of physical force, even if the bearing is tightly seated. The centering mechanism ensures the simultaneous installation of the device’s grippers. It can be used in any position. Before removing the bearing, you need to clean the armature shaft of the angle grinder from old grease, chips, sand so that nothing interferes with removing the part. The centering mechanism allows the puller to position itself precisely. If the bearing is intact, and the dismantling process is carried out for inspection, it should be pulled out by the inner ring so as not to damage it. For large anchor shafts of an angle grinder, use a massive puller with three or four gripping paws, and for small ones, devices with replaceable plates or strips are suitable.
  • Hammers, chisels, wrenches and other tools at hand. In this case, in order to remove the bearing from the anchor of the angle grinder, it is heated with gas, squeezed in a vice, grinded, chopped and many other operations are performed. These methods, of course, can be effective, but there is a great risk that the seat of the part will be mechanically damaged. And often the bearing itself after such manipulations without a puller will be unsuitable for further use. In addition, the performer may be injured as a result of hitting the face, eyes or head with pieces of the clip, which fly apart after impacts.

Angle grinder easy to change bearings part-1

As practice shows, pullers are more effective in this situation. They allow you to quickly, easily and without much risk remove the bearing from the armature of the power tool and inspect or replace parts. If you have to periodically carry out such operations, you should acquire such a useful device. The use of improvised devices is permissible only if you have experience in repairing power tools and an urgent replacement of a part is required.

How to remove a bearing from the armature in order to check its performance?

The condition of the bearing on the motor of the power tool must be given due attention. When it wears out above the permissible limit, overheating occurs, and the motor starts to run noisily. If the bearing is not removed from the armature in time, then the stationary and moving parts will begin to touch each other when it is running when it rotates. And this, in turn, threatens with serious damage to the electric motor. This will require replacement of the rotor or armature. Checking the bearings is fairly straightforward. To do this, you need to place the motor on a solid surface, put your hand on top of it and rotate the shaft. The rotor must move freely and not jam. If you hear scratching sounds or feel uneven rotation, this will be the first call to the fact that it is necessary to remove the bearing from the anchor and fix the malfunction.

Any bearing has backlash, that is, clearances. Their presence is quite acceptable, however, it is important that the indicators do not go beyond the permissible limits. It is necessary to check the backlash:

  • radial, or longitudinal. To do this, put the engine on a hard surface and try to tilt the shaft in different directions with your hand. The amount of offset depends on the size of the part. For household models of power tools, deviations should be barely noticeable;
  • axial. The check in this case is simpler. It is necessary to take the shaft with your hand and pull or push the rotor in the opposite direction. In household appliance motors, deviations should not exceed 3 mm. The closer this indicator is to zero, the better.

Grinder Repair – How to Replace the Gear Bearing

If during the disassembly of the electric motor you notice traces of friction of parts, it means that the bearings have worn out. It is necessary to immediately remove the bearing from the armature and replace the spare parts. This will allow you to avoid negative consequences in the form of engine breakdown or complete failure of the tool.

Features of pressing the bearing onto the engine armature

After you have successfully removed the bearing from the anchor, it is necessary to carry out a number of necessary manipulations before assembling the equipment. If you are installing new parts, it is necessary that they match exactly in width, as well as inner and outer diameters, with the old bearings. It is important that dirt or dust does not get inside the product during installation, because this can lead to corrosion, chips and all kinds of damage. The bearing is mounted on the anchor using a metal pipe, which must first be lubricated. During the pressing process, it is important to ensure that there are no distortions. You should also observe the following nuances:

  • lubricate the bearings with a special thick substance. It can be moisture resistant;
  • only ½ (for equipment rotating up to 300 rpm) or 1/3 (for faster tools) of the bearing chamber is filled with grease. You should not put more substance, because all the excess will still be squeezed out during rotation.

Sometimes the process of fitting the bearing onto the armature is simplified if it is preheated in boiling oil. However, you need to be very careful in this case and make sure that the part does not heat up above 100 ° C.