Comparison Einhell Classic TC-US 400 150 mm / 375 W

230 V

vs Jet JBOS-5 700 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.

The type of work item (nozzle) for which the machine is normally designed.

— Disk. In this case, we are talking about a tool that is designed only for disks and does not initially provide the installation of other work items (although theoretically, many grinding machines allow replacing a disk with a brush, see below). This option is found in almost all varieties (see "Machine"), with the exception of grinding and grinding — in them, the disc is necessarily combined with a tape or brush. Also note that grinding discs are different from grinding and polishing discs; see "Machine — Grinding" for details.

— Ribbon. Machines designed only for a belt are grinding machines — in other varieties, a similar work item is not used.

— Disk/tape. Machines that combine in the design of seats for the disk and for the tape. This option is found in grinding and grinding machines, while the features of the discs used for these varieties differ; see "Machine" for details.

— Disc / brush. Tools designed to use both a disc and a brush; usually, they refer to grinding and grinding machines — a stiff brush is used for cleaning and pre-treatment of the sharpened tool (for example, removing rust or hard dirt that cannot be washed off with water). Note that this option is indicated only for models that are initially equipped with brushes and/or equipped with specialized seats for them; with cer...tain tricks, the brush can also be installed on a classic grinder, originally designed only for discs, but this is still not recommended.

— Brush. Units that use only brushes during operation are usually metal. Such work items easily cope with rust, dried paint and various contaminants, but are not suitable for more or less accurate grinding, let alone sharpening. Accordingly, this option is typical for specialized grinding machines that are designed for primary processing of various surfaces before finer processing. For other tasks, "pure brush" units are not suitable, and the possibility of working with a brush can also be provided in a machine with a combined working element (see "Disc / brush" above). Therefore, there are relatively few such models.

— Sleeve. A working element used in a specialized variety of grinding machines — the so-called spindle. Such units are designed for cleaning curved surfaces, including internal — holes, figured recesses, etc. The sleeve is a cylinder with an abrasive surface, put on the engine axis (spindle). These nozzles can have different diameters. In turn, the spindle is located vertically in the centre of a flat desktop, which plays the role of a support, and during operation it not only rotates, but also oscillates up and down, which has a positive effect on the quality of grinding and ensures uniform wear of the sleeve. In many models, the desktop can tilt, which further expands the capabilities of the device

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.

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 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.

The length of the belt used in a machine with grinding functions (see "Machine"), more precisely, the total length of the entire belt ring installed on the machine.

This information is necessary to select the correct sanding belts — matching in length is essential for the proper installation and operation of the attachment. In this case, the working length, usually, is more than 2 times less than the total, and to determine it, it is worth focus on the dimensions of the desktop (see below).

Belt width for which the machine with grinding functions is designed (see "Machine"). The value of this parameter for compatibility with the tape can be different: in some models, the tape must exactly match the standard width, in others narrower tapes are allowed. From an application point of view, the larger width allows larger workpieces to be handled.

The nominal belt speed provided by the machine with the grinding function (see "Machine"). Other things being equal, a higher speed is useful for ensuring intensity and productivity, a lower speed allows for more precise control of the process. Detailed recommendations with specific figures for a particular situation can be found in special sources.