How to properly put a disc on a grinder: 3 rules that are often forgotten

Sometimes simple principles of working with angle grinders are presented as some kind of life hacks and secret secrets. In my opinion, if you are careful and just think before doing something, everything becomes obvious. I am telling you about my observations on how to properly place a disc on a grinder. It all comes down to three simple rules.

Before putting the disc, we look at the markings.

If there are any restrictions or requirements, manufacturers indicate this. I think it is important to pay attention to the speed and direction of rotation. So, for example, saw blades for wood, diamond for concrete and some for stone can be placed only on one side - in accordance with the direction of rotation of the angle grinder spindle.

The rule "put the pattern inward to the grinder" or "outward" does not work here. It all depends on the labeling. It can be different.

If the direction of rotation is not indicated, as, for example, on cutting discs for metal, installation is allowed by either side. At least I have not met any restrictions in regulatory documents and technical documentation. If you saw something like that, write in the comments. I will read it with pleasure.

Sometimes, to see the direction of rotation of the spindle, people start the grinder. Do not do this. The direction of rotation is indicated on the body of the angle grinder. It remains only to match the arrows.

If the arrow has worn off over time, apply it with a marker. Remember, the side of the information decal does not determine the direction of rotation.

When setting the circle, we take into account the base

There are many disputes on the Internet about how to properly install a metal cutting disc on a grinder - with a pattern inward or outward. I have my own opinion on this matter.

If you try to rotate the washer and the clamping nut on the spindle of the angle grinder by hand, you will see that they behave differently. The washer does not play. The nut is screwed onto the thread with a loose fit - there is a backlash. From this I conclude that the washer is the base surface.

If we look at the metal cutting wheel, we can only see the steel sleeve on one side. This metal insert is always even - it is the base. There may be burrs, sagging and other manufacturing defects on the back of the disc at the seating location.

It makes no difference which side to put a high-quality cutting disc. But if the circle is of poor quality, it is better to put it with a metal sleeve to the grinder's washer (usually with a pattern inward. Then the base of the saw wheel will be in contact with the washer (base surface) of the grinder. Beating in this case is excluded.

Please note that the stripping and flap discs are made so that you can put them only with a picture (and most importantly with a metal sleeve) to the grinder.

The way to install the clamping nut depends on the thickness of the disc

The clamping nut has two positions. On one side there is a small depression, and on the other there is a ledge. When using thin cutting discs, screw the nut with the protrusion outward. But if we take a thick wheel (grinding, grinding, flap), we put the nut with the protrusion inward. The diameter of this protrusion is 22 mm - it corresponds to the seat size of the disc.

When the disc is thick enough and we put the washer on the grinder with the protruding part inward, this protrusion additionally fixes the circle. As a result, there is less beating and vibration. Reducer bearings last longer.

That's all for me today. If the material was useful to you, do not forget about the "thumbs up" 👍. Subscribe to a channel here.