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Comparison Grunhelm GR-31T vs Vitals Master BK 3109-4a

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Grunhelm GR-31T
Vitals Master BK 3109-4a
Grunhelm GR-31TVitals Master BK 3109-4a
Outdated ProductOutdated Product
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Main
Four stroke engine. Convenient line replacement. Three attachments included (blade knife, line reel and saw blade). Backpack strap.
Typegrass trimmergrass trimmer
Motor typepetrolpetrol
Mowing
Cutting width44 cm43 cm
Trimmer blade width25.4 cm25.5 cm
Cutting systemrotaryrotary
Trimmer design
Motor locationtoptop
Shaft typestraightstraight
Handle typebike handlebike handle
Line diameter2 mm2.4 mm
More features
backpack
shoulder
In box
Nozzles
2-tooth blade
spool of line
saw blade
2-tooth blade
spool of line
saw blade
Motor
ICE type4-stroke4-stroke
Motor power3.8 hp1.1 hp
Motor power2800 W800 W
Fuel tank volume0.65 L
0.65 L /oil tank volume — 0.07 L/
General
Deck materialplasticplastic
Noise level114 dB
Weight7 kg9 kg
Added to E-Catalogmarch 2019june 2017

Cutting width

The capture width provided by the unit, in other words, the width of the strip of land cultivated in one pass. In fact, this size corresponds to the width of the working nozzle.

The large working width is useful when processing large open spaces, as it allows you to finish the job in a small number of passes. On the other hand, for hard-to-reach places, relatively narrow tools are better suited, able to go where a wider unit will not fit. In addition, the width of the tool directly affects the weight and price.

In general, it makes sense to compare in terms of working width only units of the same type (see above). However, it is worth noting here that trimmers do not differ so much from each other — most models capture from 25 to 45 cm (and a wide processing band is provided by moving the nozzle from side to side). As for the other types, in the most modest models the capture width does not exceed 40 cm, in the heaviest and most powerful it can be 56 – 60 cm or even more(in mini tractors — up to 1.5 m).

Trimmer blade width

The width (diameter) of the trimmer knife characterizes the size of the paddle knife (or saw blade). Such a nozzle has a smaller capture width than a fishing line, however, it allows you to mow more dense thickets, including shrubs.

Line diameter

The diameter of the fishing line supplied with the trimmer (more precisely, with a reel attachment, see "Tips").

In modern models, this parameter can be from 1 to 4 mm. At the same time, a thicker fishing line handles better with dense thickets, but it works rougher, the treated lawn is not particularly even, and for the effective operation of such a nozzle, a fairly powerful engine is needed. On the other hand, a fine line provides a clean and neat cut, but is not suitable for heavy vegetation and large stems. Thus, thick fishing line is usually equipped with powerful units designed for "launched" lawns with an abundance of thick stems. Thin, on the other hand, is found mainly in low-power electric trimmers with a lower engine location, designed for neat lawns with regularly cut grass.

We also recall that many trimmers have the ability to replace the standard reel with another one that differs in line thickness.

More features

Adjustment of the tilt of the rod. Possibility to tilt the rod or the working head relative to the rod. The setting will come in handy for mowing grass in hard-to-reach places. Trimmers with this function are much more convenient to work under swings, benches and garden furniture. Also, by adjusting the tilt of the rod, you can adjust the grip of the trimmer to the height of the user.

Telescopic rod. Possibility of increasing the length of the trimmer by extending the rod. Due to design features, this solution is available only for models with a lower engine and helps to maximally adjust the device for a person of any height.

Collapsible rod. Possibility to disassemble the trimmer rod into several parts. This feature greatly simplifies storage and transportation: packing, carrying and transporting side-by-side components is easier than a solid long rod. In theory, this design is less reliable than a non-removable design, but trimmers are usually not subjected to such high loads that this would be noticeable.

- Belt. The strap for carrying the trimmer is a shoulder or backpack strap. This design significantly simplifies the operator’s task and reduces operator fatigue: carrying it with a belt is not as tiring as holding the tool in your...hands. The shoulder strap is supposed to be worn over one shoulder. It helps you control the trimmer better and reduces fatigue, especially during long periods of use. A more complex backpack strap system allows you to distribute the weight of the tool on both shoulders and back. In this implementation, the belt will not slip off the shoulder when wearing the trimmer. Please note that in models without a belt, it may be possible to purchase it separately. However, it is easier (and often cheaper) to immediately buy a tool with this accessory.

Limit bracket. The bracket acts as a limiter and is designed to protect tall (necessary) vegetation from mowing. Those. you can extend a small structural element at the base of the rod, which, when approaching the bushes, will move them away, thereby not cutting them off. The bracket will also be appropriate when mowing an area with a fence, decorative landscape with many elements that can be damaged during mowing, or can once again “shorten” the fishing line by breaking its ends.

Rotating head. Possibility of rotating the trimmer working attachment on the rod. Typically this function is used to move the cutting system from a horizontal to a vertical position. Vertical cutting can be useful, for example, for leveling edges and creating borders in lawns.

Edging roller. The roller is necessary for a neat “haircut” between the lawn and the sidewalk. It is found in models with a rotating head and is designed for more comfortable work. Since the device does not need to be suspended, leaning on the roller makes it much easier to edge flower beds, decorative elements on the lawn, borders, etc.

Support rollers. Special rollers mounted on the cutting head of the trimmer. Thanks to such rollers, you can rest the head on the ground and roll the tool in front of you - this is more convenient than carrying it “on yourself”. Another advantage is that the rollers support the working attachment at the same height, which means that mowing is as accurate as possible, almost like using a regular lawn mower (with all the advantages of a trimmer). The main disadvantages of models with rollers are the high cost, as well as increased weight, which makes it difficult to work “off the ground.”

Motor power

Lawnmower engine power expressed in horsepower. The common unit of power these days is the watt, but gasoline and diesel engines (see "Engine Type") are traditionally referred to as hp. Some units are easy to convert to others: 1 hp. approximately equal to 735 watts.

In general, the more powerful the engine, the more performant the mower is and the better it handles with heavy work such as cutting thick grass, bushes, etc. On the other hand, high power has a corresponding effect on fuel consumption, as well as the weight and price of the engine. In addition, it should be taken into account that different types of mowers (see "Type") differ in terms of power requirements. For example, among trimmers there are many models with a capacity of 0.7 – 1.3 hp., for gasoline lawn mowers, the minimum power is already in the range of 1.3 – 2 hp., and for mowers, at least 2.5 hp is required. . So you can only compare units of the same type in terms of power. Detailed recommendations for choosing a mower depending on its type and features of the planned work can be found in special sources.

Motor power

Lawnmower engine power expressed in watts. This designation is used absolutely for all electric models (see "Engine type"), and it is also often found in gasoline and diesel units along with horsepower (these units are clearly related, 1 hp is about 735 watts).

In general, the more powerful the engine, the more performant the mower and the better it will cope with heavy work such as cutting thick grass, bushes, etc. On the other hand, high power has a corresponding effect on fuel / electricity consumption, as well as the weight and price of the engine. In addition, note that the power requirements depend on the type of mower itself and its engine (see above for both). For example, for most robots, the power does not exceed 500 W — more, taking into account specialization, is not required, besides, otherwise the devices would turn out to be too bulky and heavy. Trimmers and lawn mowers of similar power are only electric, and the power limit for power tools is 2500 – 3000 W when powered from the mains and 1500 – 2000 W for battery models. But in gasoline tools, the minimum power is about 500 – 1000 W for trimmers and 1000 – 1500 W for mowers; the maximum value can exceed 4 kW.

Detailed recommendations for choosing a lawn mower d...epending on its type and features of the planned work can be found in special sources.

Noise level

The level of noise produced by the device during operation. Usually, a certain average indicator is indicated in the characteristics — in the standard mode of operation; however, the actual values usually do not differ much from the claimed ones.

The lower the noise level, the more convenient the unit to use and the less tired the operator. In the case of lawn mowers, this is especially true, since such equipment is quite noisy — even the quietest models (some robots) give out about 47 – 48 dB, which is comparable to talking at an average volume. Note that the decibel is a non-linear quantity, and it is easiest to evaluate the actual loudness using comparative tables. Here is the simplest table for the values found in modern lawn mowers:

— 60 – 65 dB — talking in raised tones at a distance of about 1 m;
70 dB — loud conversation of several people at the same distance;
75 dB — loud laughter at a distance of 1 m;
80 dB — motorcycle engine, medium power vacuum cleaner.
90 dB — loud screams, freight car at a distance of 7 – 10 m;
100 dB — a subway train or a loud car signal at a distance of 5 – 7 m, an industrial workshop;
110 dB — tractor engine at a distance of about 1 m.

In addition to subjective sensations, there are specific sanitary standards that limit the impact of strong noise. So, according to European standards, noise of 85 dB is allowed to be heard without protective equipment for 8 hours, 91 dB — 2 hours, 97...dB — half an hour, and 103 dB — only 7 minutes. So when choosing a unit, you should take into account the duration of work with it — with high noise, you may need protective headphones.
Grunhelm GR-31T often compared
Vitals Master BK 3109-4a often compared