Attachments
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For bushes. Nozzle designed for cutting branches of small thickness, characteristic of most shrubs. The general principle of operation of such a device is similar to clippers: there are two sets of teeth located close to each other, one of them is stationary, and the second moves back and forth at high speed during operation. As a result, each pair of movable and fixed teeth works in the manner of scissors, cutting leaves and branches that have fallen under the blades. The nozzle itself looks like a web stretched forward, on both sides of which the teeth are located; this allows you to move it in any direction during operation — to the right or left, depending on the situation. It should be noted that bush nozzles are able to cope with branches up to 2-3 cm (depending on engine power), but they are still not designed for use as full-fledged saws.
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For grass. Attachments for cutting grass and leaves. Like bush (see above), two rows of teeth are used; and in general, a brush cutter with such a nozzle looks like an enlarged clipper, only not for hair, but for grass. At the same time, it is worth noting that it is not able to replace a full-fledged lawn mower: the cutting width most often does not exceed 20 cm, and the devices themselves are usually small battery models (see "Power") and are not structurally designed to work with large areas. Their main purpose is the decorative processing of small flo
...wer beds, as well as edges that a conventional lawn mower cannot reach.
— Saw blade. Such nozzles are very similar to the working element of a chain saw: an elongated rounded base (tyre), along the edge of which cutting teeth move during operation. They are designed to cut thick branches that ordinary bush attachments (see above) cannot handle, and are used primarily in pole cutters (see "Type").Pole length
The length of the bar usually refers to the total length of the brush attachment or saw blade (see Attachments) supplied with the hedge trimmer. The
longer the tire, the longer the cut that the tool can make at a time. In general, it is believed that a short length is typical for entry-level tools, while professional ones are equipped with larger attachments. However, here you need to take into account that the choice depends not only on the scale, but also on the specifics of the intended work: long attachments are less maneuverable and less suitable for topiary trimming of bushes. In addition, the cost of a brush cutter also largely depends on this parameter.
Tooth pitch
The distance between the individual teeth of the shrub attachment (see "Tips") supplied with the tool. The
larger the pitch of the teeth, the easier the tool will cope with thick branches, however, the quality of the work will be quite rough. Conversely, more densely spaced teeth work "cleaner" but are less suited to tough conditions and large branches.
Stroke frequency
The frequency of movement of the teeth in bush or grass attachments (see "Tips"). The design of most of these tools is such that for one revolution of the engine, the teeth make one complete cycle of movement back and forth; therefore, the stroke rate is usually determined by the speed of rotation of the engine and is indicated in revolutions per minute.
It is believed that the quality of the tool’s work largely depends on this parameter: the more often the stroke, the cleaner the cut will be. Ratings up to 2200 rpm are usually typical for entry-level devices, up to 2800 rpm are average, and advanced models can have speeds of 3400 rpm and even higher.
Capacity
The capacity
of the battery that comes standard with the battery-powered hedge trimmer (see above). Expressed in amp-hours, one ampere-hour means that the battery is capable of delivering 1 amp for 1 hour.
Last but not least, the battery life of the tool depends on the capacity of the battery. However, it is impossible to directly evaluate the battery life of a brush cutter by this parameter: the fact is that it depends on a number of other factors, ranging from engine power and battery operating voltage to the degree of complexity of work and contamination of the nozzle. Therefore, it makes sense to compare different models with each other in terms of battery capacity only if they do not have significant differences in other characteristics. But at the same time,
brush cutters with a capacious battery a priori allow the device to work more.
Operating time
The maximum time for which the cordless hedge trimmer can work without additional charging. Note that the maximum period is indicated, which is often overestimated by the manufacturer and is calculated at idle. Under load, this parameter will be less.
Charging time
The time it takes to charge the brush cutter battery from 0 to 100%.
Noise level
Approximate noise level produced by the hedge trimmer in normal operation. This parameter allows you to evaluate how comfortable it will be to work with the tool: the lower the noise level, the less discomfort it causes for the operator and others, and the lower the likelihood that special hearing protection will be needed during operation. At the same time, note that loud noise is an inevitable side effect of high power — it would be too expensive and difficult to make a powerful and low-noise tool. In addition, this figure is only approximate. Firstly, different manufacturers may indicate it differently: for idling, for full speed, for half power, etc. Secondly, the actual volume of work may also differ from the claimed one due to the peculiarities of a particular situation: for example, working with thick branches leads to an increase in the load on the engine, which can also affect the noise level.
Another specific point is that the decibel used to measure this indicator is a non-linear value: an increase of 1 dB corresponds to an increase of 1.26 times, 3 dB — 2 times, etc. Therefore, to assess the loudness of work, it is easiest to use comparative tables. Here is one of the simplified versions of such a table for the range in which most modern hedge trimmers work:
65 dB — loud conversation at a distance of a metre;
70 dB — loud conversation of several people at the same distance;
75 dB — shout from the same distance;
80 dB — the ringin...g of a mechanical alarm clock, a loud cry at a distance of 1 m;
85 dB — loud screams at a distance of 1 m;
90 dB — heavy truck or freight car at a distance of 7 m;
95 dB — subway car at a distance of 7 m;
100 dB — noisy industrial shop.
Weight
The total weight of the brush cutter. Usually indicated for a fully equipped tool, with an attachment installed and, in the case of a petrol engine, a full tank of fuel; however, there may be exceptions. Usually, the relevant data is indicated in the official documentation.
This parameter is important, first of all, taking into account the fact that the tool during work will have to be kept on weight most of the time. Accordingly, the lighter the brush cutter, the longer you can work with it without interruption, the less often you have to rest. On the other hand, a large weight also has its advantages: a heavy tool is more stable and does not “tear out of hand” as much under high loads on the nozzle.
