How to disassemble a grinder: instructions, diagnostic features

The angle grinder is one of the main tools of the master. LBM converts electrical energy into mechanical energy, due to which you can saw, cut, grind or even drill. It consists of two parts: mechanical - a gear unit, and electrical - an electric motor. Grinder repair it costs a lot of money in the workshop and does not always justify itself. Therefore, before you get discouraged, try to fix the problem on your own.

How to disassemble angle grinder

Troubleshooting is simple: everything is already provided by the manufacturers. The main thing - act carefully and don't overdo it, because the grinder contains fragile plastic and aluminum elements.

When it is necessary?

The problem of angle grinders is its erroneous exploitation: intense or extreme. Exist standard set of faults. These include:

• Lack of power - cable break or button breakage.
• Movement at low speeds - closing the turns of the rotor winding.
• Overheating - overload, violation of modes of work - rest. Dust sometimes builds up in the engine.
• Smoke - short circuit in the windings of the rotor or starter, dust.
• Lack of rotation - jamming of the gear of the gear unit or destruction of the bearing.
• Breakage of the spindle fixing button - wear of the stem or the presence of dust inside.
• Noise and rustling - Gear abrasion or lack of lubrication.
• Vibration - bearing failure.
• Sparks, burning smell - wear of graphite brushes.
• Working at high speeds - starter short circuit.

Correct electrical diagnostics is very important. The success of the whole business will depend on this.

Tools

Researching the problems of an angle grinder will require a standard set of tools. These include:

• Screwdrivers and wrenches.
• Pliers, hammer.
• Gas key.
• Multimeter or indicator screwdriver.

Substantially make the work of a vice easier, and a pre-prepared rag and solvent will help to avoid unpleasant consequences.

How to disassemble a small grinder

First thing remove the disc and the protective casing from the angle grinder. Next, we act according to the scheme - step by step and carefully.

Step-by-step diagnostics of the electrical part

It is important to have initial skills of working with a multimeter and have this device with you. It can be partially replaced by an indicator screwdriver. Blocks that break in the grinder:

1. Power wire. You will need to disassemble the hand of the grinder. We check if there is voltage at the switch terminals.
2. Start button. More often it gets clogged with dust. We remove the button, set the multimeter to ring and check the contacts by clicking on it. If a malfunction is detected, we replace it completely.
3. Electrical start-up and control units. If the grinder is equipped with a soft start or speed control, these elements can also fail. The first is checked using an ammeter, measuring the current surge with and without an element. The failure of the second is immediately noticeable by the nature of the tool.
4. Starter. To check, measure the resistance on its windings, having previously disconnected it from the power circuit. The value of an element is approximately 1 Ohm, a faulty one is from 10 to 100 or more. In addition, carbon deposits may be present on the inside of the housing. The short circuit of the starter turns is detected on a special stand. In the event of a breakdown, it is either rewound or replaced with a new one.
5. Anchor. Checking for a winding break is simple with a multimeter. To do this, resistance is measured in a circle on adjacent collector plates on the rotor shaft. It should be the same and within 1 Ohm. The turn-to-turn closure of the armature is checked at the stand. In any case, if it breaks down, it will be easier to buy a new one than to rewind it yourself.
6. Carbon brushes. This is a consumable angle grinder, therefore, in some cases, a technical window is provided for checking it. It is simple to examine them for abrasion: the thickness must be at least 8 millimeters. Otherwise, they must be replaced.

It is not difficult to eliminate all malfunctions - it is enough to act carefully and strictly according to the instructions.

Step-by-step mechanical check

In this case diagnosis is much easier. This does not require special skills or tools. Malfunctions are of the following types:

1. Locking button retraction. To do this, check its stem and spring. Lubricate elements and replace defective ones.
2. Gear wear. For diagnostics, the gearbox is disassembled and the condition of the teeth themselves is checked. If they are worn out, they are replaced with new ones.
3. Destruction of the rotor bearing. In this case, the grinder will vibrate. Disassembly of the reducer will be required to make a reinstallation.

Most often, gears and bearings fail. Both of these elements require replacement if broken.

Preventive actions

To avoid breakdowns and expensive repairs, you need to monitor the condition of the grinder. There must be sufficient lubricant in the gearbox. In this case, you need to use special materialsrather than the cheapest. You should not overload the instrument with work for which it was not designed, and also turn it on for a long time.

Careful attitude to the instrument will keep its performance for years to come.

It is important to follow the regimens. Dust can also be very harmful to the tool. Subject to all these rules and careful handling, the grinder will last a long time and will not cause problems.

As a rule, it is easy to identify most of the malfunctions of the grinder on your own. A minor breakdown is eliminated on its own, a large one requires the hands of a master to replace an element and some investments. Important determine in advance the cost and feasibility of this procedure. This will help you decide whether to repair the instrument or buy a new angle grinder.