How to put a disc on an angle grinder

How to remove it?

Discs, especially those designed for cutting, burn out quickly and have to be replaced.

It will be useful to remind once again about the need to disconnect the “angle grinder” from the network. Work to be done with fast rotating parts and better protect yourself.

If you need to replace a worn disk, you need to perform a number of simple operations.

  • The disc is secured to the stem stem with a threaded nut. In the kit of any angle grinder there is a special key, on the arms of which pins are fixed, which cling to the holes of the flange.
  • The spindle is fixed with a special button, the cotter pin of which, when pressed, enters the hole of the gearbox, thus fixing it. Having pressed the button with your right hand, at the same time with your left hand you need to unscrew the fastening nut with a wrench. If the nut has moved from its place, unscrew it by hand. That’s it, now the disc can be removed.
  • There are times when the key, for some reason, was not at hand. What to do? The easiest way out is to stop working. But, as they say, this is not our method. It is also possible to unscrew the clamping nut of the “angle grinder” without a key. Often a pipe (gas) wrench is used for this. On such a key there is a device that spreads it. It is necessary to tighten the nut and, fixing the gearbox of the “angle grinder” with a button, move it from its place. Then it can be unscrewed by hand.
  • There are holes in the nut for fixing it with pins on the key horns, you can unscrew it by tapping with a hammer on a chisel or a bar that is pressed into the hole.
  • It is sometimes possible to push the nut off by simply tapping its edge with a hammer in the direction of twisting. However, in this case, damage to the flange may occur, especially the holes for the pins of the key; in the future, it may be impossible to apply the key to such a nut.
  • A very good result is obtained when using a nail to make a key. It is better to choose a large nail, from 100 mm. Using a hammer and pliers, the nail is U-shaped. With a hacksaw or chisel, the point and head of the nail are cut off. With such an improvised wrench, you can try to knock off the nut. You can bend the ends of such a key, then it will turn into a kind of open-end key, but this will require a lot of labor. You can also insert a gate, for example, a hammer or other nail, into the arc formed by a bent nail.

How to properly place a disc on an angle grinder?

The disc of the “angle grinder” (angle grinder) is one of its main working parts. It is the disc that determines the use of the instrument. With it, this machine can be used to cut, grind or polish various materials. Discs, depending on the purpose, differ from each other: from abrasive chips. for metal, steel milling cutters and circular saws. for woodworking, with diamond dusting. for stone and tiles, all kinds of brushes, brushes and emery wheels. for polishing various surfaces.

The disc of the “angle grinder” is a consumable material; you cannot save on it in the process of work. The disc will gradually wear out (burn out) and must be replaced. When planning work, you need to be prepared for this and it is better to stock up on several removable disks in advance.

How to change a disk if it is jammed?

What to do if the wheel on the “angle grinder” is stuck? This can happen, for example, when, as a result of work, pieces of the workpiece being cut sharply clamp the rotating disc. This often leads to its destruction.

To unscrew the nut tightened as a result of rotation, if the circle is bitten, it can be very difficult.

  • One of these methods would be to use two gas keys at once. In this case, the remains of the disc must be broken with pliers. With one key, you need to clamp the part of the stem located under the disc, and with the other, unscrew the flange.
  • Sometimes, in order to gain access of the gas wrench to the rod of the “angle grinder”, you have to disassemble the gearbox.
  • A simple device saves from the problem of a jammed nut. cardboard or tin washers. They are often sold with an “angle grinder”. But over time, they can be lost or become completely unusable. Making homemade washers is not at all difficult. However, it is better not to neglect them.

How to change cutting disc on Black&Decker angle grinder?. Bob The Tool Man

In extreme cases, the flange can be sawn with a hacksaw for metal and then replaced with a new one.

How to install correctly?

Installing a disk on an UMSH is not so difficult. You can change it simply by following the instructions, although there are some nuances here.

First of all, you need to install the disc in the correct direction. This is especially important if it is detachable. Usually the side of the disc with the label on which the marking is indicated and, accordingly, the scope of its application, is slightly different from the opposite side. It may not appear immediately, but with prolonged intensive work, the difference will not only be noticeable. it will be obvious.

On the side on which the label is glued, a wide pressure washer is placed, and the movable nut acts on it when tightening (installing the disc). The nut slides on the polished surface of the washer, without it it will become more difficult to tighten or unscrew, since the abrasive will firmly hold the nut and more effort will be required. This is especially important if a quick replacement of the disc is required or if it breaks down (jamming).

There is always a chance of disc failure, but installed correctly, it breaks only under heavy loads, the structure of the discs takes into account the difference in loads on both sides.

With circular saws or other products that have teeth or a significant difference in two sides, there is usually no problem how to set. For example, a grinding disc cannot be fixed on the contrary: it will simply be impossible for them to work.

disc, angle, grinder

Discs for stone, including diamond ones, have a special rotation indicator in the form of an arrow: when installing them, you need to fasten them taking into account where the rod will rotate.

It is also important to consider the size of the disk when installing. In no case should you neglect safety and remove the protective cover. it is better to choose a disc of the appropriate diameter. Sometimes a worn-out disc from a large unit is placed on a smaller “angle grinder”. However, a worn disc, as a rule, cuts worse, the working surface is limited to about half the radius of the disc, the structure is slightly different. The disc burns faster and does less work. This operation can be justified if the diameter of the stem is the same. But you won’t be able to change it back.

Debris must not fall under the disc during installation. Of course, the clamping nut may well squeeze small objects, something will press into the surface of the circle. But an imperceptible skew will cause a displacement of the plane of rotation and, as a result, a strong vibration of the entire mechanism, it can cause the destruction of the disc and, of course, you should not hope for an accurate cut in this case.

Before installing the disc, the “angle grinder” must be disconnected from the mains. this is the main safety requirement, since a sudden turn on at this time is fraught with serious injuries.

The clamping nut must be unscrewed with the wrench supplied with the tool. To prevent the stem from spinning, it must be locked by pressing a special button. It is necessary to unscrew the nut while keeping the button pressed.

After twisting the nut, the disc is put on the released stem, with the front side out, and you need to make sure that it is installed exactly in the seat.

The kit for the new “angle grinder” always includes a certain amount of cardboard spacers. when installing the disc, they must be laid so that they are between the disc and the clamping elements. These gaskets will help unscrew a broken or jammed disc.

Further, the nut is manually tightened up to the stop and tightened with a special wrench. That’s it, the “angle grinder” is ready to go.


If you had to use a gas wrench, you must remember about the very powerful shoulder of such a wrench and about the effort that is applied to the parts of the “angle grinder”. If you do not act carefully, the spindle lock could be ripped off or the gearbox could be damaged.

All manipulations with the disc of the angle grinder must be carried out with the power supply completely disconnected (the plug must be removed from the socket). Any inadvertent pressing of the start button will cause the electric motor to turn on, and the rod rotation speed is very high. In this case, injuries cannot be avoided.

Working with an “angle grinder” involves a lot of waste in the form of metal or wood shavings and dust. Before starting work, you must wear special safety glasses: they will protect your eyes from fragments of the cutting wheel itself in the event of its jamming and destruction.

Glasses are needed not only as a safety element. If the eyes are protected, more attention can be paid directly to the work of the “angle grinder“, to ensure the correct cut or the choice of the correct mode of operation. This will allow the most efficient use of consumables (cutting wheels), minimizes the occurrence of abnormal situations with a biting disc or its destruction.

A protective mask that completely covers the face will perfectly replace glasses. this is especially important for a visually impaired master who wears diopter glasses, on which safety glasses cannot be worn.

The disc on the “angle grinder” can be installed both “away from you” and “towards you”, depending on the direction of rotation and, accordingly, the flow of chips. This does not make a fundamental difference in work. However, the “angle grinder” with a circle “towards itself” when biting the disc tends to jump out of the cut forward, and not on the one who uses it. This is especially important when working with powerful tools, but even a small angle grinder can be a serious hazard.

A specially mounted extension cord with a plug socket, preferably without grounding, will help to quickly stop the operation of a machine that has escaped from the hands.

“Angle grinder” is a rough processing tool and it is not worth striving to obtain an ideal surface as a result of its work, the main thing is to make a rough cut, which later, if necessary, can be processed in other ways.

To work without clamps and jamming, it is better not to cut long metal workpieces to the end, leaving 1–2 mm of metal in the cut: they will be easy to break off afterwards, this will practically not affect the quality of the workpiece.

It is better to place small workpieces in a vice or press them with a clamp to a workbench or other reliable horizontal surface. The quality of the cut and safety depend on the density of pressing.

How to put the disc on the “angle grinder” can be seen in the following video.

The main difference between the two sides of a circle

On any cutting disc, two surfaces are clearly visible. One of them (back) is monophonic, formed by an abrasive material. The second (front) has a label containing basic information about the characteristics of the disc. But the main distinguishing feature of the two surfaces is the presence of a metal ring on the front side.

Prescribing instructions

The instructions for many angle grinders, such as the Metabo WP 850, clearly state that “the metal flange of the abrasive cut-off wheels must be in contact with the support flange”. Manufacturers do not give such recommendations in vain, since they ensure safe operation of the tool, reduce the risk of serious injury to the master.

Advantages of ring-mounted disc to angle grinder

The cut-off wheels do not have a programmed direction of rotation. Therefore, it does not matter which side will carry out their installation. But as mentioned above, installing the circle with its front side outward facilitates the process of replacing it (it is much more difficult to unscrew the nut on the abrasive side). In addition, such an installation provides several more advantages.

Guaranteed even installation on the shaft

The metal ring increases the footprint. Therefore, when the disc is installed on the shaft and starts to tighten with the nut, the pressure is evenly distributed. This ensures a smooth fit of the cut-off wheel and reduces the likelihood of damage from skewing.

Which side to put the cut-off wheel on the angle grinder

Angle grinder (angle grinder) or, as it is also called, “angle grinder” is a widespread tool with which craftsmen saw, cut, grind various kinds of surfaces. During work, it is often necessary to replace the working disk. And at this moment, many people have a question about which side to put the cutting disc on the angle grinder.

Ease of disk installation

Installing the abrasive wheel face-out provides another advantage. you will always visually see which nozzle (for metal or stone) is currently installed on the angle grinder. They are not interchangeable and, if mistaken, there is a high likelihood of serious consequences. For example, when trying to use a cutting disc for metal cutting through concrete, it may be destroyed and traumatized by the resulting pieces of the master. Therefore, installing the abrasive wheel with the label facing out will provide not only convenience, but also safety of work.

disc, angle, grinder

Why do you need a metal ring

The metal washer (ring) is designed to protect the integrity of the disk when it is tightened with a movable flange nut, as well as to increase the bearing surface area. In addition, the metal washer does not allow the cutting disc to “stick” to the nut surface, which greatly facilitates the process of its replacement.

The main difference between the two sides of a circle

On any angle grinder disc, you can easily notice differences on the two sides of the wheel. One side is plain, it is covered with abrasive materials (for working with different types of metals). The front side has a special label on which they write information about the characteristics of the cutter.

But the main difference between the two sides of the circle is the presence of a metal ring. This is an important design element that affects the safety of use, and therefore deserves a separate mention.

Why do you need a metal ring

A washer or simply a metal ring is necessary to protect the abrasive from excessive tightening, since many users tend to tighten the stopper tighter, fearing that the circle will fly off while working with the tool.

Also, the ring is mounted on an angle grinder disc to significantly increase the bearing surface area. In addition, the washer is designed so that the abrasive does not “stick” to the nut, which simplifies the removal process.

Advantages of ring-mounted disc to angle grinder

There is no exact direction to follow when setting the wheel to the sander. But, as already described above, if you put the cutter “face” out, then the removal process will be simplified, since it is more difficult to catch on the surface from the abrasive side.

Apart from this, there are a few more benefits that will be useful to know about.

Which side to install the disc on the angle grinder

Placing the disc on an angle grinder is easy if you follow some fairly simple instructions. This information is extremely important to the wizards, as it is the disc that determines the functionality of the instrument. With the disc, you can use the angle grinder (angle grinder) to grind, cut or polish various kinds of materials. How to properly place the disc on an angle grinder, further in the article.

For metal

How to properly place a wheel on an angle grinder is influenced by two factors:

  • Any abrasive has a special label that shows the side to which it needs to be attached to the angle grinder. If the angle grinder is working away from the operator, as it should be in most cases, then the disc must be installed with the label facing inward. When the angle grinder runs in the opposite direction, the label is on the outside.
  • Of course, you can put the abrasive on either side without paying attention to the label. But in this case, you need to expect unpredictable results, for example, disk breakage.

Important! Experts assure that if you do not follow the requirements for installing the disc, then the angle grinder will jam one day, the disc can fly apart, damaging the operator working with the tool.

Prescribing instructions

On some models of grinders, for example, Metabo, it is indicated that the metal flange of the abrasive must be adjacent to the supported flange of the angle grinder. It is not for nothing that manufacturers recommend installing the disc in this way, since they rely on safety when working with the tool.

Important! Improper installation is life-threatening.

Which side to put the disc on the angle grinder

In most cases, the abrasive for an angle grinder is installed in only one direction, but in a situation when working with stone or concrete, the process changes. Therefore, you need to consider these cases separately.

Place the disc differently depending on the situation.

DeWalt Angle grinder Disc install: How to install the disc

Guaranteed even installation on the shaft

A metal ring on the disc increases the bearing area so that the tightening pressure becomes even. Thus, the disc will sit as smoothly as possible on the desired surface. The possibility of skewing will be excluded. This directly affects not only the evenness of the cut, but also the safety of the user. the abrasive will not fly into pieces if it does not cling to the angle grinder.