How to easily unscrew the nut of an angle grinder if the disc is jammed

A variety of mechanisms make our work easier, both in production and in everyday life. But sometimes they present unexpected and not very pleasant “surprises”. After all, it is impossible to foresee all situations in which you will have to use tools.
This also applies to an angle grinder (angle grinder), when the cutting disc is clamped so tightly on it that neither a standard wrench nor other tools or methods can be used to unscrew the clamping nut. In this case, there is a danger of breaking the quick-clamping button for the disk and even the body of the tool, which is usually made of aluminum alloy. The matter is further complicated by the fact that the surface to which the working disk is pressed is often round and cannot be stopped.

Why does the lock nut tighten?

The grinder, depending on the brand and diameter of the working disk, develops from 6,000 to 12,000 revolutions per minute. When the rotating disk sharply touches the surface being processed, the following rapid processes occur.
The cutting disc, cutting into the material, experiences great resistance and slows down somewhat, but the rotor of the electric motor rotates by inertia for a few more moments at the same speed and literally screws the spindle thread into the locking nut, pressing it into the cutting wheel. Now it will not be easy to unscrew it, especially with the original key.

There are various ways to get rid of this defect. Not all of them pass without a trace for the instrument. Here we will look at one of them, which can be called auto thermal.

How to remove a disc clamp on an angle grinder

To implement this method, you will need some kind of massive wooden material: a piece of thick board, a piece of timber, or just a stump.

Then we take a grinder with a tightly clamped disk, turn on the tool and, with sufficient force, press the fixing nut to the surface of the stump so that it continuously rubs against the wooden surface.

The process must be continued for two to three minutes. This time is enough for the clamping nut not just to heat up, but to become hot. If heating is not stopped in time, there is a risk of damage to the spindle bearing due to overheating.

The degree of adequacy of the thermal effect on the fixing nut can be checked using a pipette with water: drops from it instantly evaporate as soon as they reach its surface.

Next we proceed in the standard way. Press the quick disk replacement button and use a standard wrench to unscrew the nut without any effort. In this case, the well-known property of metal, which expands when heated, helps us.

The nut unscrews with absolutely no extra effort.

Notes and Tips

To reduce the likelihood of clamping the working disk on the angle grinder, you should load the tool smoothly to prevent the disk from braking when it comes into contact with the material being processed.
The disk should be installed on the spindle with the pattern (marking) facing outwards (towards the clamping nut), since it is on this side that there is a wide metal washer on the disk. If a disk jams or breaks, the movable clamp will be easier to handle because it will slide on a metal washer rather than on the rough surface of the disk.
It helps to place a washer made of cardboard or other not too hard material under the nut. But this method is not specified by the tool manufacturer, since this may disrupt the balancing and does not guarantee the reliability of fastening the disk to the spindle.
You can heat the locking nut using a blowtorch or gas torch. The heat source in this case does not matter. The main thing is not to overdo it with heating, so as not to damage the spindle bearing.

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