Comparison Eltos MZ-510 104 mm / 510 W

230 V

LED light

vs CRAFT-TEC PXBG-203 200 mm / 900 W

230 V

The number of rotation modules provided in the design of the machine. The rotation module in this case is a separate “seat” on which one or another element can be installed (disk, sanding belt, etc., depending on the type of machine).

The features of this parameter directly depend on the type of tool (see "Machine"):

— 1. "Single-shot" grinders are usually models that can work with specific types of sharpening (see below) and often do not support universal sharpening at all; in addition, models for a sleeve have a similar design (see "Working element"). In grinding machines, in turn, the presence of one rotation module means working only with a sanding belt, without additional devices. Surface stitching machines, by definition, have only one rotation module, but this option is not found in other varieties.

— 2. Two rotation modules allow you to install two work items on the machine and perform different types of work on it without wasting time on changing nozzles. For example, in grinding machines, a grinding disc can be placed on one module, and a metal brush on the other for pre-treatment of the tool before sharpening; in grinding machines, the second module can be responsible for the operation of the grinding wheel, etc. At the same time, such a design does not particularly affect the cost of the unit and is easily implemented in most modern machines, even very simple ones.

— 3. Three working nozzles installed at the same tim...e, further expand the capabilities of the machine, but significantly affect its price, dimensions and energy consumption (in fact, the engine has to constantly rotate two modules idle), while the real need for such versatility arises very rarely. Therefore, this option is found only in single models of grinding machines.

Mutual arrangement of rotation modules in models with more than one such modules (see above).

— Aligned. Rotation modules located on the same axis — usually, on different sides of the casing with the engine. The most simple and at the same time reliable option used in most modern machines.

— At a right angle. In such machines (usually they belong to grinding machines, see “Machine”), the axis of one of the rotation modules is located as in the coaxial ones described above, and the second module is rotated 90 ° — thus, the plane of rotation of the disk is in front (or behind) from the body. This option allows you to use larger discs than in coaxial models, as well as to equip them with wet baths without much difficulty (see below). On the other hand, the arrangement at an angle complicates and increases the cost of the design.

Rated power of the electric motor of the machine. The more powerful the engine, the higher the speed and intensity of processing can be, the larger discs can be used with the machine and the better it is suitable for working with hard, stubborn materials. On the other hand, a powerful motor consumes a lot of energy (which may require special connection — see "Power") and significantly affects the dimensions, weight and price of the entire unit. Therefore, manufacturers choose this parameter based on the type (see "Machine") and the desired characteristics of speed, productivity, etc. In fact, this means that engine power is rather a secondary parameter, and when choosing, it makes sense to pay attention to more practical points — disk diameter, rotation / movement speed, etc.

The presence in the design of the machine of a mechanism for changing the placement of the chain relative to the grinding disk. The sharpening angle of the saw chain largely depends on the main purpose of the tool: for transverse or longitudinal sawing. Since the resistance of wood is always noticeably higher during longitudinal sawing, the edge of the tooth must also be very sharp. Knowing the maximum value of the sharpening angle will be very useful before buying a grinder.

Types of tools and other devices for which the unit with sharpening functions is designed to work (see "Machine")

— Chains. Grinding machines for sharpening the working blades of chain saws — the actual chains. The teeth on such chains require special processing — in particular, the use of thin discs. The machines themselves also have a specific design — most often the rotation module (it is one) is installed in an inclined position on a fixed base and can be raised / lowered (although there are other design options).

— Drill. Units for this purpose, usually, have nests where drills are inserted during processing; each socket is designed for a different drill diameter. Theoretically, the drill can be sharpened on a universal machine (see below), but this requires certain skills — while processing on a specialized machine, on the contrary, is extremely simple.

— Knives. In this case, we mean models that have specialized equipment for working with knives, scissors and other similar bladed tools. Such equipment ensures that the tool being sharpened is held in the optimal position relative to the disk and reduces the risk of “messing up” during sharpening, making this type of machine generally more convenient than universal ones (which are also often used for sharpening knives). On the other hand, knife equipment may not be suitable for some specific...jobs.

— Milling cutters and drills. Machine tools designed to work with drills and cutters, usually, are rather complex units equipped with clamps with an abundance of adjustments. This allows you to easily set the optimal position of the tool being sharpened, and also provides other features necessary for this type of work. At the same time, the design features of such machines make them suitable for universal sharpening, this option, usually, is also indicated in the characteristics.

— Saw blades. Models for sharpening circular saw blades have two distinctive features: a small blade thickness that allows you to work without problems in the space between individual teeth, and a special attachment for the saw blade — usually in the form of a freely rotating axis with a clamp. The disk is fixed on this axis, after which each tooth is processed in turn by the disk.

— Universal. In this case, traditional sharpening is meant using a rotating disk of a rather large thickness, in which the tool to be sharpened is processed by the side of this disk and is held, usually, manually. This sharpening method is really suitable for a very wide variety of tools and fixtures, with a certain skill and the availability of appropriate disks, drills, knives and even saw blades and chains can be sharpened in this way. The main disadvantage of universal sharpening can be called the manual hold itself: it is less reliable than using clamps, and besides, the operator requires a rather high accuracy of movements — otherwise, the quality of sharpening can be worsened, or even ruin the tool. However, some machines with this function are equipped with fixtures for workpieces.

There are grinders that combine several types of sharpening described above — for example, models in which one of the rotating modules is supplemented with a mount for saw blades, or units with recesses of various shapes — for knives and drills.

Regular diameter of the disk (see "Working element") used by the machine for dry processing (see above). When grinding and polishing, usually, we are talking about the maximum diameter of the disk that can be installed on the tool — a larger nozzle will either be ineffective or not fit into the dimensions of the seat at all, but a smaller diameter disk, usually, is installed without problems (of course, if the hole diameter matches — see below). For grinding machines, the diameter of the disc corresponds to the diameter of the sanding pad, which is necessary for the full use of the disc.

The larger the regular disk — the heavier and more powerful the machine, usually, the better it can cope with complex work of a large volume. At the same time, for small everyday tasks like periodically sharpening knives or chisels, a small disc is quite enough.

The bore diameter of the dry cutting discs (see above) used by the machine. In order for the nozzle to be used normally with the machine, it must match it not only in diameter and thickness (see the relevant paragraphs), but also in the size of the mounting hole.

The thickness of the "dry" blade (see "Dry Machining") for which the machine is designed. Usually, we are talking about the maximum thickness of the disc that can fit on the seat — most models allow the use of thinner nozzles.

Note that this parameter depends on the type of sharpening (see above): working with chains and saw blades involves a small thickness of the discs, universal sharpening is the opposite. And for grinding models, the thickness of the disc is not relevant at all, even if the disc is provided in the design; see "Machine" for details.

The nominal speed of rotation of the disk for dry processing (see above), provided by the machine; for models with adjustable rotation (see below), the maximum rotation speed.

For the same disc diameter and material, a higher speed provides more intensive processing, and a slower rotation contributes to accuracy and precision. In addition, optimal speeds depend on the composition of the disc and the material being processed; detailed recommendations with specific figures for a particular situation can be found in special sources.

A separate category is grinding machines with disk-shaped working elements: in such units, the actual speed of movement of the disk surface relative to the workpiece depends on how close the contact point is to the centre of the disk.