Impact energy
The energy transmitted by the perforator to the material being processed upon impact; the higher this indicator, the stronger and more powerful each individual blow.
First of all, we recall that the energy of impacts is directly related to their frequency: an increase in frequency leads to a decrease in energy. Therefore, for models where the number of strokes can be adjusted, this paragraph usually gives the maximum energy achieved at the minimum speed of operation.
In general, higher impact energy improves efficiency when working with hard, stubborn materials, but requires more motor power (especially if it has to be combined with a high frequency). Therefore, it is worth choosing according to this parameter, taking into account specific tasks. So, for occasional use in everyday life, an energy of 2 J or less is enough, for home repair work of medium intensity, at least 3 J is desirable; a power of
4 J or more is already considered high; and in some industrial-grade perforators, this figure can reach 30 J.
Rotation speed
The speed of rotation of the working equipment provided by the rotary hammer. Usually, this indicates the speed at idle, without load; rated load speeds can be further specified in the characteristics (see below), but this is rare, and this parameter is still considered the main characteristic. It is also worth mentioning that in the presence of a speed controller (see "Functions"), the maximum speed value is given here.
When working in the main mode — drilling with impact — the rotation of the equipment is used mainly to remove waste from the hole, and the revolutions here are of no fundamental importance (they can be very low). Therefore, it is worth paying attention to this indicator mainly in cases where the rotary hammer is planned to be often used for conventional drilling, without impact. And here it is worth proceeding from the fact that
high speeds increase productivity and contribute to accuracy when working with some materials, but reduce torque (compared to tools with the same engine power). So for heavy work with hard, stubborn materials, relatively "slow" tools are usually better suited.
Note also that drilling is not the main task of rotary hammers; therefore, their rotation speeds are noticeably lower than those of the same
drills. On the other hand, in this case, low speeds are often compensated by powerful engines and high torque, which makes it possible to effectively drill holes
...of a fairly large diameter, including using crowns.Wood drilling max. ⌀
The maximum diameter of a tool that can be used with a rotary hammer when drilling in wood (and, accordingly, the maximum diameter of the resulting hole). With a large drilling diameter, the loads on the device increase, and some models may simply not be designed for them (despite the technical possibility of installing tools of the appropriate diameter), as a result, it is not worth exceeding the maximum specified diameter, because. this may damage the instrument.
Concrete drilling max. ⌀
The maximum tool diameter that can be used with a rotary hammer when drilling in concrete. See "Maximum drilling diameter in wood" for details.
Max. hole saw ⌀
The maximum tool diameter that can be used with a rotary hammer when drilling with a hollow core. Crowns are used to create holes of large diameter (from 40 mm) in hard materials such as reinforced concrete and stone. See "Maximum drilling diameter in wood" for details on the maximum diameter.
Compatible batteries
The name of the battery that is compatible with the device. It helps to buy a spare or find a suitable one in case of a breakdown of the main one.
Weight
The weight of a fully assembled rotary hammer (in the case of battery power, with a standard battery installed). Unlike many other types of equipment, in the case of rotary hammers, light weight is far from always an advantage. So, heavy models are better suited for professional use — they are less prone to vibrations and, usually, are stronger, which is important when working with difficult-to-cut materials for a long time. But for small, simple works of short duration, a lot of weight is not required, and in this case,
light models are useful, which do not require significant effort to hold on weight.