Installing the cutter on the grass trimmer

Knife, cutter, disc, guard, belt for grass trimmer

Operating a brushcutter is difficult enough without a number of optional accessories, which include a cutting headset, as well as a shoulder strap and a guard that protects the operator’s feet from rocks and grass. Each of these devices has its own important role in the grass trimmer set, so to study their characteristics and the choice should be taken with the utmost responsibility.

It is not uncommon for homeowners to use a variety of knives and discs to care for the area. Their main function is the control of large weeds and old dried out shrubs. In most cases, manufacturers use such materials to produce the knives:

  • metal. steel blades have one important function. they are designed primarily to cut the thickest weeds and or young wild tree shoots, with a maximum thickness of 3 mm. Metal blade for grass trimmer can be used only for regular installation on brushcutters with power not less than 1,5 l. с.;
  • Plastic. the headset made of this material is more fragile, but it has less weight, which allows using it on amateur trimmers, power from 0.8 to 1.5 liters. с. Plastic brushcutter blades are also rust-resistant.

Knives for trimmers also differ in the type of cutting edges. The cutting attachment can have 4, 8 or more teeth that are positioned at the same height or on top of each other. Metal blades are also available with a carbide tip or with holes in the teeth.

The cutting attachments can also be made in the form of several blades or as a solid disc with sturdy metal teeth.

Choice of blade according to conditions of use

Each replaceable blade for grass trimmer is distinguished by its size and device. These factors dictate whether it can be used with a brushcutter with a specific power and shape of boom. For example, if the factory tool boom is curved in a J shape, it is not recommended to use a metal blade to work with it, because if the latter strikes a foreign solid object, the tool will quickly bounce back to the operator’s feet. In this case, even a sturdy blade guard can’t protect against injury. It is best to use a steel cutting blade on brushcutters with straight bars because the rebound distance will be greatly increased when working with them.

When selecting a cutting attachment, please note the material of the attachment. As a rule, metal tools are used to fight particularly large weeds. Nevertheless, plastic blades can handle most wild plants. In addition, plastic is much lighter and more flexible, and grass trimmer blades and discs made of it put less strain on the motor and drive shaft of the tool.

The quality of cutting vegetation is largely influenced by the type of cutting edges. In order to combat tough vegetation, woody shoots and dead wood, it is best to choose the disc for the lawnmower, which is equipped with a large number of teeth. The result will be a neat and even cut, regardless of the type of weeds.

Which blades should I use on my lawnmower and electric mower?

Before buying and installing a knife on a brushcutter, let’s find out what they are and when they are used. Today manufacturers offer the consumer a large number of types of these consumables. In general, all cutting tools designed for mowing the grass can be classified:

The main material for trimmer blades can be plastic or metal. The use of such expendable elements largely depends on two parameters:

For safety reasons, manufacturers do not recommend putting steel blades on electric grass trimmers. Almost all brushcutters running on an electric and battery-powered network are equipped with plastic blades. Depending on the manufacturer, they can be solid disc-shaped design, with several blades, or in the form of a special mowing head that provides for installation of removable plastic blades.

The gasoline grass trimmer has a straight shaft and the electric one has a curved shaft

To put a metal blade on the electric trimmer for grass does not allow its design features.

  • The machine’s curved boom reduces the distance from its working part to the mower’s feet. In the event of a collision between blades and a stone or other hard object, the grass trimmer swings back to your feet.
  • The high torque we mentioned above, if the metal blade collides with a hard object, transmits more stress to the flexible shaft of the grass trimmer and its motor. Which causes their premature failure.
  • Handle of an electric mower most often does not have a limiting strip that serves as a stop. That does not rule out foot injuries.

These features enable to use plastic blades only on trimmers with electric motors. On encountering an obstacle, the blades collapse, thus protecting the mower’s legs from possible injury.

Plastic blades are good for overgrown and dry grass. They are capable of mowing nettles and burdock stems.

Only gasoline-powered trimmers are equipped with metal blades, just because of their design features.

  • Straight boom design increases distance to the legs, which provides complete safety to the operator.
  • Comfortable U-shaped and J-shaped handles hold the tool firmly. D-shaped handles brushcutter is equipped with a limiter that rests against the leg of the mower, which does not allow the head to let go of the legs when the cutting disc meets a solid obstacle.
  • The clutch on the petrol engine allows a smooth acceleration to the optimum speed. And when the blade hits a hard surface, it can absorb some of the impact.

So, gasoline grass trimmers with a metal blade installed are best used on large areas. They can successfully cope not only with high rough grass, weeds, burdocks and nettles, but also with bushes and young trees.

The blade shape of the blade on the weed trimmer does not influence the quality of the work done. No dependence on them for speed. Triangular, trapezoidal, rectangular shapes are all a marketing ploy by manufacturers.

If you are planning to make hay, it is best to use a brushcutter with more blades. Please pay attention to discs with eight teeth or discs with four big blades and four extra ones. Two- and three-blade blades will shred grass hard.

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How to properly install a blade on a grass trimmer

Put a knife on the trimmer for grass is not so difficult. The manufacturer has its tools with a special pin, allowing you to lock the gear and a wrench that unscrew the bobbin with a fishing line. The most important thing is to observe safety rules and the sequence of disassembly when changing cutting elements.

Algorithm of installation of the blade on the grass trimmer is as follows:

  • Remove the protective cover;
  • Lock the drive. This is done by aligning the two holes. in the hub of the shaft and in the gear cup. After their alignment insert a pin in the holes;
  • Unscrew clockwise from the hub bobbin with a fishing line or a nut retaining the dust cover (if the grass trimmer has not yet been used);
  • Next, we install the cutting blade, so that the slits on the hub washer coincided with the notches in the hole of the cutting disc;
  • Install the duster;
  • Tighten the fastening nut (counterclockwise) holding the locking pin;
  • Tighten it using a pipe wrench;
  • Putting the blade guard back in place.

As you can see, there is nothing difficult. Now you can safely start mowing weeds on your property.

To cut long, tough grass, or wild growth of fruit trees, it’s handy to use a trimmer with a blade. On low-power electric trimmers for grass put plastic knives, on more powerful gasoline. metal. If you have been working with a fishing line before, you need to remove the mowing head and put the blade in its place. Here are detailed instructions on how to do it.

How to correctly place the blade on the grass trimmer

Putting the blade on the weed trimmer is not that hard. The manufacturer equips its tools with a special pin that allows you to lock the gearbox and a wrench, with which the bobbin with the fishing line is unscrewed. The most important thing is to observe the safety technique and the sequence of disassembly when changing the cutting elements.

The algorithm for installing the blade on the grass trimmer is as follows:

  • We remove the blade guard;
  • Lock the drive. To do this, you must align two holes. in the hub of the shaft and in the gear cup. Once they are aligned, insert the pin in the holes;
  • We unscrew clockwise from the hub the bobbin with a line or a nut of fastening, holding the dust cap (if the grass trimmer is not used yet);
  • Then we install the cutter blade, so that the slits on the hub washer coincided with the notches in the cutter blade hole;
  • Install the duster;
  • Tighten the fastening nut (counterclockwise) while holding the locking pin;
  • Tighten it, using a pipe wrench;
  • Replace the blade guard.

As you can see, there is nothing complicated. Now you can safely proceed to mow weeds on the site.

To mow tall tough grass or cut wild growth of fruit trees, it is convenient to use a trimmer with a knife. Low-power electric grass trimmers have plastic blades, more powerful petrol trimmers have metal blades. If you have previously worked with a fishing line, remove the mowing head and replace it with the blade. Please see the detailed instructions on how to do this.

Installing the blade on the grass trimmer

Always disconnect the machine from the mains before changing the blade on your trimmer. If it is a brushcutter, switch off the engine.

  • If you haven’t used the brushcutter before, turn it off and remove the key. Fix a hexagon wrench (or a rod with a suitable diameter. it can also be a regular nail) in the hole in the gearbox. This is to prevent the shaft from turning. Unscrew the fastening nut and remove the gear cup from the shaft.
  • If a mowing head is installed. As in the 1st and 2nd chapters of this manual.1, insert the wrench into the gearbox hole. Hold the wrench and unscrew the mowing head.
  • Install the washer on the hub, then the blade. Make sure the protrusions match the notches. Then the blade will be correctly centred.
  • Put the thrust washer and gearbox cup on top of the blade.
  • Put the stem nut on the shaft and tighten counterclockwise. For this you will need a pipe socket wrench.
  • Pay attention. so that the nut is not unscrewed during operation, most gasoline trimmers have a stud, which is inserted into the hole in the shaft.

Nozzle options, nozzles for Chinese brushcutter

Manufacturers offer a variety of attachments for grass trimmers, only to choose the right one, you need to know the number of teeth on the splines. There can be 7 or 9 of them. Be careful, because the attachments for Chinese brushcutters may not fit the tools of European manufacturers and vice versa.

Let’s look at a few options.


The perfect addition to your petrol brushcutter. This gasoline-powered brushcutter is powerful, reliable and long-lasting.

Jet wheels

Used in conjunction with other attachments as needed, such as a blower, sweeper brush or roller. Thanks to the wheels, the implement can be lifted slightly, which will help reduce friction on the surface, making it easier to work, reducing wear and tear, improving quality, and making the work more enjoyable.


For pruning trees up to a height of approx. 4.5 metres. It uses the principle of a hacksaw.

Garden shears

Will help trim hedges or shaped bushes beautifully. Available in two models with different boom lengths. The choice must be made according to the situation.

Lawn aerator

Designed to saturate the top layers of soil with air by piercing it. This procedure is very useful for lawns, which are more than 5 years old and the root system is quite thickened.

In addition, it can be used to break up crust in beds and lawns after irrigation, rain, trampling, which helps increase the air permeability of the soil.

Water pump

It helps to draw water for irrigation and household purposes from a well, any container, lake or river. Also helps pump out the water from the cellar or pool.

Boat Motor

For all types of boats up to 36cm transom height. It can provide a boat speed of up to 20 kilometers per hour, but in a fair wind and the lack of countercurrent.

Cultivator attachment on brushcutter and reviews of it

This brushcutter attachment has received the greatest number of positive reviews among gardeners.

It can be used to loosen the soil in seedbeds, greenhouses, flowerbeds, flower beds, around bushes and garden trees.

Using brushcutter attachments will make it a lot easier and faster to do different jobs. Easy enough to maintain and considerably cheaper in price in comparison with outboard for power tillers.

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This tool is indispensable for those who have small plots or are engaged in greenhouse farming. Cultivation procedure loosens and aerates the ground and thus has a beneficial effect on both plant development and the quality of the harvest.

The high-quality attachment of the cultivator to the trimmer makes it especially easy to use, and the rapidly rotating cutters ensure high working efficiency.

Sophisticated and quality construction allows you to operate the cultivator for many years. Safety guard eliminates the possibility of debris falling on the operator while working.

Learn more about cultivator attachments by browsing

Cultivator attachment on the brushcutter and reviews about it

This attachment on the brushcutter has received the greatest number of positive reviews among gardeners.

It can be used to loosen soil in seedbeds, greenhouses, flowerbeds, flower beds, around bushes and garden trees.

Using brushcutter attachments will make various jobs much easier and faster. Easy enough to service, and the price is much cheaper in comparison with the outboard for power tillers.

It is a necessary tool for those, who have small areas or engaged in greenhouse farming. Cultivation procedure allows to loosen soil and saturate it with oxygen, which positively affects the development of plants, as well as the quality of the resulting crop.

Particular convenience when using the cultivator provides quality attachment device on the trimmer, the rapidly rotating blades provide high performance.

Sophisticated, quality construction ensures the cultivator can be used for many years. Safety guard avoids the possibility of debris falling on the operator while working.

installing, cutter, grass, trimmer

Learn more about cultivator attachments by browsing

Attachment methods and design

Modern attachments-cultivators can be made in two versions:

Despite the different names and designs, by and large the fundamental difference is only in the form of the ripper unit.

installing, cutter, grass, trimmer

Toothed grass trimmer nozzles have less weight, and therefore are better suited for processing light soils. As for the disc models, they are used to loosen the heavier soils, because they have greater rigidity.

Turning torque is transmitted to the mowing head from the engine thanks to the shaft, which is composed by means of a special rod. The latter, unfortunately, often has to be bought separately.

The unit in question is not interchangeable and the number of splines on the end of the rod can vary from 7 to 9. On this basis, buying a tool-cultivator, for example, from Oleo-Mac, you should know that it will not work with Husqvarna trimmer, and vice versa.

Slotted method of fixing cutters or discs to the shaft provides a free displacement of the cutting bodies, so the soil will be loosened with a fairly wide coverage. 200-250 millimeters. This option is excellent for the purpose of cultivating the land on the plot, because it eliminates a large amplitude of boom displacement during the work. In addition, this method allows to reduce or even eliminate the limitations on the density of beds.

When treating long beds, the process of working with a nozzle and trimmer becomes even more convenient, because in this case you will have to make turns much less often.

Nuances when working with a cultivator nozzle

It is important to emphasize that any kind of attachment noticeably increases the weight of the tool as a whole, and the weight increase is often at least 5-6 kg. That is why continuous work with a trimmer in this case becomes a force not for everyone! On top of this, when choosing a nozzle, it is important to take into account the mechanical limitations of the power drive of the device. For example, if you have selected the model grass trimmer with an engine capacity of less than 1500 watts, then the treatment of the soil will be limited to only dipping potato bushes and seedbeds, as you can work only with regularly loosened soil!

Since the drive shaft has a considerable length, and the drive itself in trimmers working on gasoline, as a rule, is located behind the working, then during cultivation works are accompanied by significant vibrations, the magnitude of which may vary depending on the load on the blades and discs, as well as the length of the shaft itself. These vibrations are transmitted directly to the person’s hands through the shoulder strap, so it can be difficult to hold a large unit and operate the cultivation button at the same time. It is important to point out that a long soil treatment with a tiller head is not always safe for the health of the operator.

But there are also advantages: the increased mobility of the mounted gasoline grass trimmer with the absence of wheels makes it possible to easily work with soil on row-spacing and beds without damaging the already planted plants.

It is important to note that nozzles-cultivators “do not get along” with caked soils, because at the first introduction in such a layer boom abruptly thrown back. Bearing this in mind, many manufacturers equip disc cultivators with special safety guards, making it more likely that the toothed blades bend rather than break. In the latter case, however, at least a small protective cover for the feet is not superfluous.

The presence of the safety screen significantly reduces the visibility of the worker!

Weeder on brushcutter. functions and instructions for use

Often farmers use a brushcutter with a standard line mower head for removing vegetation between the potato rows. This method has proven ineffective, because it only removes the top of the weeds. Their root system is still in the ground. over, when treating the row spacing with a fishing line there is a risk of damaging potato bushes and other planted crops, which leads to lower yields.

A device for weeding potatoes proved to be much more effective in such cases. It looks like a rotary cultivator and is attached to the trimmer’s engine with a separate shaft. The working organ of the weeder for grass trimmer is shaped like a goose’s claw.

The principle of operation of the device for weeding is very simple. During work on the site its working body penetrates the soil, gradually pulling weeds with their root system. an important advantage of the attachment is that it does not cut the wild vegetation, but pulls it completely, preventing the subsequent germination of weeds.

When working with the weeder for grass trimmer, you should follow a number of rules.

  • During operation constantly monitor the oil level in the gearbox;
  • after each row, remove any accumulated vegetation from the tools. If there are a lot of weeds in the area, you will need to do it more often;
  • Try to exclude the possibility of the working bodies of the grass trimmer nozzle on rocks and other solid objects;
  • Monitor the condition of the metal parts of the weed trimmer. If there are scratches on it, the metal will need to be primed and painted to avoid the formation of rust.
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If you notice that the grass trimmer is making squeaking noises during use, it indicates that the bearings of the tool are worn out. Defective parts should be quickly replaced to avoid increased wear and tear of the tool.

Pole pruning attachment for brushcutters. design and benefits

The pole pruner for grass trimmers is used for cutting rotten and dry twigs up to a height of 3 m. The device consists of a straight metal boom, the length of which is usually 1.5-2 m. The bar and the steel chain attached to it are fixed to the upper part of the boom. In most cases, the width of the standard chain is 1 to 3 mm. Weight of the Pole Pruner is low and rarely exceeds 2 kg. This gives the owner of the attachment the ability to work long hours with the trimmer raised, feeling virtually no fatigue.

Some models of pole pruners are designed so that their operators can replace their standard bars and tires with larger and more efficient elements. This significantly expands the functionality of the devices and makes it possible to use them to cut trees of almost any height. The simplicity of the device of the nozzle gives every enthusiast the opportunity to assemble a homemade pole pruner for grass trimmer.

Plastic circles on a grass trimmer. when to use

If metal milling and paddle discs are used on gasoline trimmers, then it is recommended to use plastic circles for electric tools. Their main advantage is their low weight, so the load on the electric motor is completely excluded. Structurally, the head is a plastic base plate, on which knives are mounted on the perimeter. blades are made of soft plastic, which bends without deforming when in contact with an obstacle. Blades are mounted on a round base at an angle of 120 degrees.

installing, cutter, grass, trimmer

They are designed to cut dense grass with electric trimmers when a trimmer blade cannot cut it. If the mowing head has a high moment of inertia, this can be reduced by making symmetrical holes. When the teeth are blunted, they need to be sharpened at an angle of 30 degrees, using a grinding wheel with low or medium roughness.

Disc design Use Features
40 teeth milled peorized Accurate cuts in lawns and high grass. Perfect for mowing grass in fields and forest belts Eliminates grass wrapping on the disc and low gearbox load. High output for large quantities of grass
Cutter peorized with more than 40 tines (60-80) For small trees with a stem thickness of 7-8 cm Suitable for cutting grass with small growing trees
Solid with 8 to 32 teeth Cutting of thin and tough bushes in raspberry and currant bushes. Cope with grass effectively, but only with powerful machinery Effectively cuts stems of small shrubs. Put stress on gearbox
Single, double or triple blade design For tough grass, brushwood Repeatedly shredding grass, putting more strain on the gearbox
Blade with 4 blades or more Bristles and hard grass cutter, can be used for hay making Has a low moment of inertia
Plastic discs For small and dense grass in the backyard Does not stress the electric motors of trimmers

Grinding trimmer blades correctly. what you need to know about it

While using a lawn mower with metal cutting blades we can observe their dulling. It is perfectly normal, but you must not continue to use it. Blunt blades have a low performance, so in addition to unsatisfactory mowing results, you also get overheating of the tool motor and wear of the gearbox. If blades or teeth of cutting blades of trimmer are blunt, it is necessary to sharpen them. Some people prefer to buy new cutting wheels, which is not rational at all.

This is interesting!All types of cutting blades have to be sharpened, including those with pobedite tips. To sharpen a wheel with a pobedite, you will need a special diamond wheel. What is the process of sharpening the disk with a victorite plated on the teeth, described in detail in this material. Step by step description on how to sharpen a grass trimmer disc:

  • First remove the cutting attachment from the tool. It is not safe to sharpen the tool
  • Examine the element for suitability. Cracks, chips and other deformations are not permissible. If there are any, it is necessary to perform the replacement of the device
  • To sharpen the disk are used tools and materials such as a sharpener, file, angle grinder. What is the best choice depends on the skill of the operator. The easiest and safest way is to use a file. To do this, the cutting tool is attached to the jaws of the vice, and the process of sharpening is manually performed at an angle of 30 degrees
  • If a grinder or angle grinder is used, it is necessary to grind carefully. When sharpening, the metal must not be allowed to redden (there will be a vacation of metal), otherwise it will lead to rapid wear and abrasion of the cutting part
  • The optimal option, which is recommended for beginners (it is also used by masters with experience) is the use of a file. A file can be used to sharpen the cutting edge to the best possible angle, which will have a positive effect on the performance of the tool
  • If you have to sharpen a milling disc with a large number of teeth, it is recommended to use an angle grinder with a fine abrasive wheel for such cases

The video below explains how to correctly sharpen milling discs with more teeth.

After completing the work on sharpening the grass trimmer disc, it remains to install it in place, and make a test of the effectiveness of the tool. After sharpening, keep in mind that it is better not to grasp the sharp parts, as you can be injured.

To summarize, it should be noted that the effectiveness of grass mowing depends on the right choice of trimmer disc. For mowing the grass on the roadsides and paths, a line for the trimmer is used, but for fighting weeds in the countryside, as well as for making hay in the fields and in wooded areas, lawn mowers with metal discs are used. If the budget allows, it is recommended to buy 3 types of metal discs, and try them out on your own experience to feel the difference.