If strong sparking is visible in the body of the angle grinder during operation, the problem requires an immediate solution. Most often it is caused by worn or jammed brushes. But it happens that they are completely fine, but the sparking is strong. You cannot continue to use such an angle grinder, as this may cause it to fail irrevocably.
The process of diagnosing and repairing a sparking angle grinder
The first thing you need to do is remove the gearbox and get to the anchor.
You need to look at the condition of the magnet (speed sensor) on it. If it is cracked or spins, then that is the problem, and replacement is a must.
Next, you should check the resistance on the stator windings with a multimeter. It should be the same. The breakdown from the windings to the housing is also checked. If the reason is in the stator, then you will have to contact a repair shop to have it rewinded.
You also need to check the resistance between the slats on the armature. It should be the same. The breakdown from the windings to the housing is immediately checked. If the anchor is broken, the easiest way is to replace it with a new one.
In the case when the brushes, armature and stator are in order, the reason lies in the commutator.As a result of wear, it has grooves, so the brushes press against it unevenly. You need to remove the armature from the gearbox and sharpen the commutator.
After this, the sparking will stop.
