How to choose the right disc for a grinder
Grinder wheels in the retail network can be bought in a varied assortment and at low and high prices. With the help of products made of different materials and using different technologies, they perform diverse operations
What are the basic rules for choosing and what to look for? It is necessary to clearly know what materials to work with. And you also need to pay attention to such factors:
- diameter and thickness (the indicators should not be more than indicated in the passport data for the grinder, or, more simply, the disc should fit into the protective casing);
- landing size (must correspond to the diameter of the grinder's spindle);
- rotation speed (it must correspond to the type of grinder, it is indicated on the disc itself);
- type of cutting (dry, wet or combined).
The rules that must be followed to make the products last longer are simple. For hard materials, discs with a soft binding are chosen, for soft materials - with a hard one. The working area should not overheat during operations. Therefore, it is recommended to periodically remove the disc from the material to cool it down. You cannot make a deep cut in one pass. Do not press the product with great force and work at high speeds. Remember: if in the process of work there is a beating of the disc, cracks have appeared on it, such a consumable cannot be cut. It needs to be replaced.
How to use it correctly?
It is always worth remembering that the grinder is a traumatic tool
Particular attention should be paid to the cutting discs, since they often lead to deplorable situations. The sad statistics is that almost 90% of accidents when using a grinder are due to poor-quality wheels.
If the disc is selected, then when working directly with the grinder, certain safety rules must be observed.
- Always wear a face shield before cutting or peeling material. Cutting and sanding creates sparks that can enter your eyes or burn your face. Therefore, a protective mask is indispensable when working with a grinding machine. It is also recommended to wear gloves that fit snugly around your hands.
- Do not cut material at the highest RPM. In this case, the grinder can simply become uncontrollable and fly out of the hands from strong vibration. Many modern grinders are equipped with soft start functions and a speed control. This makes the job much safer.
- Keep away any flammable materials and flammable liquids when working. As already mentioned above, from working with a grinder, sparks arise, from which a fire hazardous situation can arise.
- A standard stationary grinder operates on an electrical network, so it is highly discouraged to work with it in high humidity. And it is also worthwhile to carefully examine the insulation on the tool wire before starting work.
- When cutting, hold the grinder by the handles with both hands. In this case, the disc should rotate in the direction away from the worker.
- For beginners who have no experience in cutting with a grinder, there are also a few basic rules when working with a grinder.
- Before you cut the main material, it is worth practicing on some other object. For this, reinforcement or an unnecessary metal sheet may be suitable.
- While this is not always possible, it is advisable to keep the instrument in a different line with you.
- Not all grinders gain full speed immediately when turned on.It is advisable to wait a few seconds until the grinder picks up high power, and the disc is completely spinning.
Any circle is gradually grinded, and it must be changed. In order to replace the nozzle, you need to follow the following steps:
- it is necessary to replace the nozzle only on the grinder disconnected from the power supply;
- after shutdown, it is necessary to jam the rotary shaft on which the cutting wheel is installed;
- then a nut is unscrewed with a special key that holds the disc (usually the key is included with the grinder);
- then everything is simple - the old disk is removed, a new one is installed in its place and secured with the same lock nut and the same key;
- after that, you can use the tool again - sawing or processing the material.
A carved disc for a grinder is its main element, without which high-quality work on cutting or metal processing is impossible.
The following video is devoted to a practical comparison of discs for metal from different manufacturers.
How to use?
There are several rules on how to use the disks, so as not only to perform the task correctly, but also not to suffer.
- Before turning on the grinder, regardless of which nozzle is used by the operator, it is worth looking at the element for defects. Cracks, missing pieces, or other damage to the disc are a potential hazard. Never use a damaged disc as it can potentially rip out and throw a piece of material at high speed towards a person.
- Never use a cutting disc for grinding because the product is thin and not designed to withstand lateral pressure, unlike discs used specifically for this purpose. They can bend and collapse. If the lateral edges are applied to the material, this will thin the disc, overload it and potentially lead to the fact that it simply shatters into small pieces.
- Discs should not be used at a speed higher than that for which they were designed. There is a mark on the surface indicating the maximum speed. The larger the disc, the slower its maximum rotation speed.
- Before starting work, make sure that the flange nut is tightened tightly, and the disc itself is installed correctly.
- Do not use the attachment if the expiration date has passed. The material suffers from moisture and time, loses its original qualities, which leads to softening of the binder resin and weakening of the structure.
- The “cavity” on the depressed center disc should face outward.
- If you need to cut stainless steel, use a nozzle made of a difficult abrasive material. Thinner ones are available for cutting metal and are used for metal profiles. They cut through the material quickly, with less friction, without damaging the protective coating. However, they also wear out faster. Diamond can be used to cut brick, stone, concrete, slate and tile.
- The best way to cut metal is to first mark the cut line using a Tippex mark. Then the ridges are cut first, and then the depressions. The best way to avoid rolling back is to cut the ridges from the back by pulling the grinder towards you, and then cut the indentations away from you. Sheets for metal profiles are so thin that the disc can deflect and hit with the edge, then it will simply burst. In any case, the pressure should be minimal to reduce the likelihood of such a situation developing.
For information on how to change the nozzle on the grinder, see the next video.
What are discs for grinding metal
Grinding is one of the most common processes for which a grinder is used. With this device and a set of nozzles, you can gently and roughly work on metal, wood and stone surfaces. Basically, grinding precedes the polishing of products.The attachments that are used in this situation may contain sandpaper or felt material.
For grinding metal, a variety of brushes are used, which are made from wire on a metal base. Moreover, now you can buy other, most technological nozzles for an angle grinder. The band file is direct evidence of this. It is applied for grinding, polishing and removing corrosion. Taking into account the desired quality of the plane, circles with replaceable sandpaper, felt, porous and even fabric can be mounted on an angle grinder.
Grinding wheels for metal are used to perform the following activities:
- sharpening tools;
- final processing of welds;
- cleaning the surface from paint and corrosion.
In most cases, work will require specialized abrasive pastes, and sometimes liquids. For coarse grinding and cleaning, grinding discs with a fine abrasive size are practiced. Grinding wheels for an angle grinder make it possible to refine almost all materials to the required roughness. For example, similar nozzles are used even in car services for polishing car bodies.
Selection Tips
The attachments are acquired taking into account a strictly defined speed during rotation, the correspondence between the machine and the discs for it must be absolute. Several standard sizes of wheels are produced - from 115 to 230 mm. Shaft diameter - 22.2 mm. The smaller disc is easy to install on a larger grinder using special adapters. The nozzle is secured with a nut connection, a stud with a standard M14 thread.
To choose the right disk, experts recommend paying attention to several parameters.
- Thickness. It is believed that tighter circles last longer.
- Main diameter. The larger it is, the faster the grinding occurs. Larger circles are more reliable and last longer. Craftsmen prefer universal wheels with a diameter of 125 mm. In this case, it is easy to hold the machine with one hand for precise operations. The maximum size of 230 mm is rarely used when working with wood. Natural wood is not homogeneous, so it is better to resort to a gradual and gentle sanding. For repairs, discs of 150 mm are also suitable, sometimes even 180 mm.
- Segment type. Coarse abrasives are purchased for primary processing, soft abrasives for finishing parts. Usually, in everyday life, for processing large surfaces, both hard grinding and polishing wheels are needed.