How To Properly Repair The Interskol Grinder With Your Own Hands

2023 Author: Philip Bishop | [email protected]. Last modified: 2023-08-25 07:54

Design features of the tool
Necessary tool for repairing grinder Interskol
The main electrical malfunctions of the Interskol grinder
Repair of control circuits of the grinder Interskol
How to repair the rotor of the Interskol grinder
Repair of the stator grinder Interskol
Mechanical malfunctions of the Interskol grinder
Repair of the gearbox of the grinder Interskol LBM 125
Repair of the gearbox of the grinder Interskol LBM 230
Assembling the grinder Interskol
How to assemble a reducer grinder Interskol
How to assemble a grinder Interskol
A few words about greasing the grinder Interskol
Interskol grinder repair video

Interskol angle grinders (grinders) are very reliable and durable. They are distinguished by good performance and high reliability. But, improper use of the tool, untimely replacement of carbon brushes, grease and bearings leads to premature failure.

Repair of the Interskol grinder can be done independently.

To do this, you need to know the device of the Interskol grinder, the assembly diagram, the procedure for performing technological operations when disassembling and assembling the LBM. In order to properly repair the Interskol LBM, it is enough to study the proposed scheme and instructions.

Interskol angle grinders have recently become more and more popular not only among professionals, but also among DIY enthusiasts.

Design features of the tool

Firm Interskol is the Russian leader in the development, production and sale of various power tools, recognized by world manufacturers. Interskol products are distinguished by ergonomics, simplicity and ease of maintenance, environmental friendliness, and increased power.

Interskol grinders are classified by disc diameter: 115,125,150,180,230.

Among lovers of DIY crafts, Interskol grinders of two classes are especially popular: with a disc diameter of 125 mm and 230 mm.

In the presented classes, several models are produced, differing in power.

In the 125 mm class, 4 (four) Interskol models are produced: UShM 125/900, UShM 125/1000, UShM 125 / 1100E, UShM 125 / 1400EL.

In the 230 mm class, 10 (ten) Interskol models are produced, differing from each other in terms of power. Interskol 230 class grinders are produced with a power exceeding 2000 W.

The Interskol UShM 230/2300 marking is deciphered: an angle grinder with a maximum circle diameter of 230 mm, a power of 2300 W.

At Interskol grinders 125, the driven gears are attached to the spindle by means of a keyed connection.

The grinders Interskol UShM 125 are assembled in one case, which serves as a handle.

Bulgarians Interskol UShM 230 have a convenient rear handle on the back of the body. These are powerful professional machines with a two-handed design. In this class of angle grinders, driven gears are pressed onto the spindle shaft.

In the proposed repair instructions, we will consider schemes of two classes of Interskol grinders: UShM 125, UShM 230.

Necessary tool for repairing grinder Interskol

Repair of Interskol lugs cannot be performed without a simple, necessary tool. A set of screwdrivers, open-end wrenches, a vice, a hammer, a press will help you to repair the mechanical part of the Interskol grinder. A tester is needed to repair electrical circuits. It's good if you have the opportunity to use an IK-2 type device to find short-circuited turns in windings. Of auxiliary materials, you will need grease, napkins, and flushing fluid.

To carry out a high-quality repair of an angle grinder of the Interskol family, it is necessary to prepare a workplace, choose the right lighting. On the floor, in a dark room, quality repairs are impossible.

To repair the Interskol grinder quickly and correctly, you need a diagram of the grinder that you are going to repair.

Malfunctions in grinders are divided into mechanical and electrical.

The main electrical malfunctions of the Interskol grinder

As a rule, the most common cause of a grinder's failure is an electrical malfunction. The main percentage of failure of grinders for the electrical part is the failure of carbon brushes.

Repair of control circuits of the grinder Interskol

The control circuits of different models of grinders differ slightly from each other. It all depends on the power of the tool, the availability of innovative developments. Some grinders have an integrated electronic unit that regulates the smoothness of the start.

Wiring diagram of control circuits of the grinder Interskol LBM 125

In the grinders Interskol USHM 125 electrobrushes pos. 55 are mounted in special brush holders pos. 44, which can only be reached by removing the back cover pos. 51 of the stator housing pos. 42.

After removing the cover, it is necessary to unscrew the screws pos. 50 holding the brush holder body.

The wear of the brushes is determined by their remaining length. The length of the working carbon brushes cannot be less than 5 mm.

Power is supplied through the cable pos. 53. In the places where the cable enters the grinder and into the plug pos. 53, the cable may break off. The malfunction is eliminated by replacing the entire power cord or part that has failed. No twists are allowed.

The power cable supplies voltage to the switch, pos. 41, inserted into the housing, pos. 47. There is a lever pos. 46 to operate the switch button. When performing maintenance, purge the engaging lever with silicone grease.

Wiring diagram of control circuits of the grinder Interskol LBM 230

Power is supplied through the cord, pos. 50, to the switch pos. 46, to which the electronic unit pos. 40 is connected, carbon brushes, pos. 38, inserted into the brush holders, pos. 37. The electrical part of the grinder also includes a stator pos. 32 and a rotor pos. 27.

Replacing carbon brushes on Interskol grinders 230 does not require removing the back cover. It is enough to unscrew the cap of the brush holder pos. 36 and pull out the brush holder with a carbon brush. But you can replace the switch, electronic unit, capacitor pos. 42 only by disassembling the rear handle pos. 44.45. To do this, unscrew the four screws 4 × 16 pos. 44.

How to repair the rotor of the Interskol grinder

Failure of the rotor occurs for the following reasons:

The carbon brushes have worked or are out of order;
Short circuit or breakage of windings;
The lamellas of the anchor collector worked:
Broken or seized rotor bearings.

Repairing a rotor requires special knowledge, instruments and equipment. It is preferable to buy a new rotor or send it to a specialized service center for repair. But remember, it costs money. For those who are especially gifted, we recommend rewinding the rotor with your own hands.

Use a puller to remove the bearings from the armature. But you can use improvised means. For example, a vice, strips of metal, a hammer, a soft metal guide.

Dismantling of bearings from the armature LBM 125

There are two bearings on the rotor, pos. 31: rear, near the manifold, pos. 32.

Bearing size 608Z.

And on the side of the impeller, bearing pos. 28, size 6000-2 RS. Russian analogue 180100.

The bearings are removed after dismantling the rotor from the gearbox housing. To pull the rotor out of the gearbox, it is necessary to remove the bevel drive gear pos. 26 sitting on the rotor shaft.

To do this, unscrew the M8 × 3.5 nut, pos. 25, dismantle the drive gear Z = 12. It is fixed with a key, pos. 30. The bearings are removed with a puller.

Dismantling of bearings from the armature LBM 230

To remove the bearings from the armature pos. 27, it is necessary to pull the rotor out of the gear housing, pos. 19. Unscrew the M8 nut, pos. 20, remove the lock washer, pos. 21, dismantle the drive gear, pos. 22. gently shaking it, pull the rotor out of the gearbox housing. The bearing will remain in the gear housing. It is closed by a bearing cap, pos. 25, which is attached to the gear case with three screws M5 × 8, pos. 26. A bearing of size 6201-2RS is installed in the gearbox housing. Russian analogue 180201.

From the side of the collector, the bearing pos. 28 is removed using a puller. Bearing size 608RT. Russian analogue 180608.

Repair of the stator grinder Interskol

Repair of the stator of any Interskol grinder is carried out after determining the nature of the malfunction. Most often, the stator burns out. This is due to overheating of the instrument. An involuntary uncontrolled unwinding of the grinder's rotor indicates a malfunction of the stator.

To repair the stator, pull it out of the housing. It is possible to check the performance of the stator without removing it from the housing. But this can only be done in specialized workshops. Or if you have an IK-2 short-circuited loop control device. It is possible to determine an open or short circuit in the stator windings without dismantling the stator. The burned-out stator is removed, rewound, or a new one is installed instead.

The burned-out stator can be rewound by yourself.

The rewind algorithm is as follows:

Cut the damaged winding in any way from one edge;
Count the number of turns of the winding, determine the direction of its winding, the percentage of filling the groove of the stator core, measure the diameter of the wire;
After removing the burned-out winding, clean the core grooves, check the insulation;
With the prepared wire, wind the required number of turns of the stator windings into the prepared grooves;
Solder the ends of the windings, after putting an insulating wire on them;
Impregnate the stator windings using alternating current;
You clean the traces of impregnation inside and outside on the stator housing;
Check the free movement of the rotor inside the stator.

DIY Interskol grinder stator repair video

Video:

Mechanical malfunctions of the Interskol grinder

Of the mechanical faults in Interskol grinders, the gearbox remains a weak point. The gears used in the gearbox wear out over time, the teeth are destroyed, and backlash appears in the joints.

Repair of the gearbox of the grinder Interskol LBM 125

In order to repair the gearbox of the Interskol grinder, it is necessary to establish the nature of the malfunction. Most mechanical gearbox failures are detected visually or by ear. Large runout of the spindle shaft, jamming or turning of the gears of the gearbox are determined by a simple inspection of the condition of the spindle shaft. And the increased noise during the operation of the gearbox, uncharacteristic sounds, overheating can be determined by ear or by touching the body with a hand.

To disassemble the gearbox, unscrew (4) four screws M4 × 14 pos. 11, remove the spring washers DU-1000ER pos. 12, pull out the gear cover, pos. 13. The mounted spindle, pos. 10, will remain in it. The spindle is mounted in the bearing, pos. 14. Bearing size 6201-2RZ. Russian analogue 180201.

Use a press to push the spindle out of the bearing housing. But you can gently knock out with a hammer. The main thing is not to damage the gearbox housing cover.

The bevel gear wheel pos. 16 is held on the keyed connection and is fixed with a retaining ring pos. 17. A ball with a diameter of 3 mm is used as a key in the Interskol UShM 125/900 grinder. If you remove the retaining ring, it is not difficult to remove the gearwheel. In other models of Interskol grinders, UHM 125 uses a key.

Remove the gears and inspect for teeth licking, crushing or biting, or play in the keyed connection.

Repair of the gearbox of the grinder Interskol LBM 230

To disassemble the gearbox LBM 230, remove the cover pos. 6 by unscrewing 4 (four) screws. The spindle, pos. 8, is held in the bearing, pos. 9, pressed into the cover body, pos. 6. Bearing size 6203zz. Russian analogue 180203.

The gear wheel pos. 11 is pressed onto the spindle with an interference fit. To remove it, you need a press. Craftsmen manage to remove with a hammer, preheating the gear.

Remove the gears and inspect them for teeth licking, destruction.

Repair of the grinder Interskol LBM 230

Video:

Assembling the grinder Interskol

The assembly of the Interskol grinder is no different from the assembly of other brands of grinders. Serviceable parts and assemblies freed from old grease are allowed to be assembled. The assembly consists of several stages.

How to assemble a reducer grinder Interskol

To assemble the reducer assembly, you must assemble the spindle by putting bearings and bevel gears on it.

On the spindle pos. 10 put on the cover of the gear housing pos. 13, bearing pos. 14, bearing caps pos. 15, bevel gear wheel pos. 16. The gear is fixed to the spindle with a key connection. In lumbar 125, a ball with a diameter of 3 mm is used as a key. To fix it on the spindle, the gear is fixed with a retaining ring, pos. 17. The assembled spindle is inserted into the needle bearing, pos. 18. And the needle bearing is pressed into the gear case, pos. 21.

The assembly of the gearbox LBM 230 begins with the assembly of the spindle assembly, pos. 8, onto which the bearing, pos. 9, and the circlip, pos. 10, are fitted. Gear wheel pos. 11 is pressed onto the spindle. The spindle is inserted into the roller bearing, pos. 12. Standard size of the bearing NK1210.

To facilitate the process of pressing the driven gear, pos. 11, onto the spindle, pos. 8, heat the gear and cool the spindle.

How to assemble a grinder Interskol

The assembly algorithm for the Interskol grinder is as follows:

The stator is inserted into the housing;
The stator is covered with a plastic protection;
A rotor is inserted into the stator with a protected rubber sleeve on the collector bearing;
The second end of the rotor is inserted into the gearbox housing;
The drive gear is mounted on the rotor and fixed with a nut with a right-hand thread;
The gearbox housing is fixed to the stator housing with four screws;
The smoothness of the rotor rotation is checked;
A cover with a driven gear is put on the gearbox housing;
4 (four) screws for fixing the gearbox cover are tightened;
The smoothness of turning the tool spindle is checked;
Carbon brushes are installed;
The back cover is put on or the handle is assembled;
A test run of the tool is carried out, the smoothness of operation is checked.

According to the given algorithm, all grinders of the Interskol family are assembled without exception.

Several features when disassembling and assembling the Interskol grinder:

For high-quality removal of old grease from the gearbox housing, it is better to warm up the latter with a professional hairdryer to the liquid state of the grease and then remove it;
In some models of Interskol grinders, the drive gear is fixed on the shaft with two nuts, one of which is a lock wrench S = 12;
Carefully unscrew or tighten the fixing nut of the rotor driven gear in the grinders Interskol UHM 115;
Put lubricant in the gear case, which is less than half of its volume;
When disassembling, carefully inspect the condition of the collector lamellas, there should be no traces of burning and worn out tracks on it.

A few words about greasing the grinder Interskol

Before assembling the mechanical units of the Interskol grinder, without fail, lubricate the parts with the recommended lubricant. Lubricants of foreign and Russian manufacturers are widely represented on the Russian lubricant market. Today you can buy high-quality lubricants from a domestic manufacturer. They are in no way inferior in quality to foreign counterparts, but are several times cheaper.

A special grease with high adhesion has been developed for the grinder gearboxes. Adhesion is the property of a substance to adhere to a lubricated surface.