How To Put The Disc On The Video Trimmer

What knives to put on an electric and lawn mower

Before buying and putting a knife on a lawn mower, find out what they are and in what cases they are used. Today manufacturers offer the consumer a large number of types of these consumables. In general, all cutting tools designed for mowing grass can be classified:

• By the type of material from which it is made;
• By the shape of its cutting blades.

The main material for making trimmer knives can be plastic or metal. The use of such consumables largely depends on two parameters:

• Lawn mowers type;
• Mowing areas.

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

Straight bar for petrol trimmer and curved for electric

To put a metal knife on an electric trimmer is not allowed by its design features.

• The curved bar of the machine reduces the distance from its working part to the mower’s feet. In the event of a collision of the blades with a stone or other solid object, the scythe is thrown to the feet.
• The high torque we mentioned above, in the event of a metal blade hitting a hard object, transfers a large load to the trimmer flex shaft and its motor. What causes them to fail prematurely.
• The handle of the electric scythe most often does not have a limiting bar acting as a stop. Which does not exclude injury to the legs.

It is these features that make it possible to use exclusively plastic knives on trimmers with electric motors. When colliding with an obstacle, the blades are destroyed, thereby protecting the mower’s legs from possible injury.

The use of metal knives only on gasoline trimmers is also due to design features.

• Straight bar design increases leg clearance for complete safety.
• Comfortable U-shaped and J-shaped handles provide a firm grip. D-shaped handles of lawn mowers are equipped with a limiter that rests on the leg of the mower, which does not allow the head to come close to the feet when the cutting disc meets a solid obstacle.
• The clutch of the gasoline engine allows for smooth acceleration to the optimum level. And when the blade hits a hard surface, it is able to absorb part of the impact.

Thus, petrol trimmers with a metal blade installed are best used in large areas. They will successfully cope not only with high coarse grass, weeds, burdocks and nettles, but also shrubs, as well as young trees.

The shape of the blades of the disc supplied to the trimmer does not in any way affect the quality of the work performed. Speed ​​does not depend on them either. Triangular, trapezoidal, rectangular shapes are all marketing ploy of manufacturers.

Why you need to put the knife on the trimmer

A trimmer with a knife mounted on it is most convenient to use for more comfortable mowing of tall and coarse grass in the country. The line on the lawn mower fails in such cases. Thin breaks very quickly. Using 2.3mm thick cord or homemade rods with cables causes the vegetation to wrap around the spool. This increases the load on the engine. As a result, the piston group and other moving parts of the unit wear out very quickly.

If the weeds are mowed with an electric trimmer without a knife, only a fishing line, even a thick one with a curly section, will not solve the problem. There is always a risk of overheating the motor and damaging the flexible shaft. And it’s all about the large torque of the electric motor. Grass wrapped around the spindle creates strong resistance to the shaft, which resembles a speedometer cable, which does not withstand and twists.

In order to protect equipment from premature wear, manufacturers have provided for the possibility of installing special knives on the trimmers. The design and shape of the existing cutting elements allows you to easily cope not only with coarse and overgrown grass, but also successfully deal with young shrub growth.

How to put the knife on the trimmer

With the arrival of summer, many owners of personal plots are worried about the question of how to put the knife on the trimmer. No less relevant are the questions of why and when it is advisable to replace the line on a lawn mower with a more durable cutting element. In our article we will try to disassemble all this and give useful recommendations to summer residents.

How to put a knife on the trimmer correctly

Putting the knife on the trimmer is not that difficult. The manufacturer completes its tools with a special pin that allows you to block the gearbox and a wrench with which the spool and fishing line are unscrewed. The most important thing is to observe safety precautions and the sequence of assembly and disassembly when changing cutting elements.

The algorithm for setting the knife to the trimmer is as follows:

• Remove the protective cover;
• We block the drive. To do this, it is necessary to align two holes. in the shaft hub and in the gearbox cup. After combining them, insert a pin into the holes;
• We unscrew the spool with line or the fastening nut holding the boot (if the trimmer has not been used yet) from the hub clockwise;
• Next, install the cutting knife so that the slots on the hub washer coincide with the recesses in the hole of the cutting disc;
• Install the boot;
• We tighten the fastening nut (counterclockwise) while holding the locking pin;
• We tighten it using a tubular wrench;
• Putting back the protective cover.

As you can see, there is nothing complicated. Now you can safely start mowing weeds on the site.

Trimmer disc installation procedure

Attaching the blade to the trimmer is easy. For this, a complete wrench is used that disconnects the cutting attachment and a pin that blocks the gearbox. The procedure is as follows.

• First of all, the electric trimmer should be disconnected from the network, the petrol trimmer should be simply turned off. Detach and move the protective cover to the side.
• Next, you need to align the holes on the gearbox and the shaft in order to insert a pin into them and block the drive.
• If a spool with line was used, it must be unscrewed clockwise.
• Then you need to find a nut to twist the knife.
• The next step is to install the knives. Trimmer owners often wonder which side to put the disc on. This must be done so that the marking with numbers and letters is on top.
• Then you need to put a boot on top, and above it. a fixing nut, which must be tightened tightly with a wrench.
• The last step is to install the protective cover.

As you can see, the procedure is very simple and the same for many brands, whether it is Stihl or Husqvarna.

Material

It is not recommended to put metal knives on electric scythes, since the design features make their use dangerous for the user. This is due to the curved shape of the rod, the absence of stops on the handles, as well as the high rotation speed.

On gooseneck trimmers, plastic blades should be used for safety reasons. Their purpose is to mow soft grasses, dead wood. Whereas metal discs do an excellent job with tall, dense, hard shoots, shrubs, and tree shoots.

Lawn mower disc features

Knife discs are produced in plastic and metal, as well as in various shapes to perform diverse tasks.

• Two-, three- and four-bladed knives with pronounced blades are used for mowing grass and tree growth. However, they are not suitable for making hay, as they grind the shoots, chopping them several times.
• The massive four-blade discs are designed not only for clearing the ground from grass, but also for mowing hay. They prevent repeated cutting of the shoots, thus making them suitable for harvesting for the winter.
• Discs with cutting edges around the perimeter are relevant for beveling reeds and reeds. These knives are very heavy. a necessary quality to cut through thick stems.
• Professional saw blades for brush cutters and lawn mowers for cutting small trees and bushes.

Plastic knives are used as an alternative to metal discs. They do not need to be firmly fixed in the head, but they rotate as a result of the action of centrifugal force. The strength of plastic knives is high, so the service life is quite long.

Blades

The number of blades is important when solving diverse tasks. So, two or three pieces are enough to grind the grass. To harvest hay, it is necessary that the disc has four to eight blades. To destroy small shoots of trees and shrubs, instead of blades, the discs should have a large number of small teeth.

When is the use of knives relevant?

When using lawn mowers in summer cottages, the fishing line is the most popular attachment. It has a low price, is suitable for different trim heads, and is safe to use. The disadvantage of using a fishing line is that it is convenient only for mowing low growth. In other situations, the string will hit immediately, regardless of whether a petrol or electric trimmer is used. In addition, vegetation is wound around the spindle, which creates significant resistance on the shaft and leads to its breakage. It can also cause the piston system to fail in lawn mowers or to burn out the motor in trimmers.

Therefore, for mowing tall or hard vegetation, various attachments are used. So, for harvesting tall and coarse grass, thin shoots of trees and shrubs, it is better to install and use a disc. This nozzle clogs up much less frequently, which contributes to greater wear resistance of the equipment.

Rules for replacing knives on the grass trimmer

If the trimmer disc is used regularly, it will need to be removed from time to time and sharpened or replaced with a new one. This part can be made of metal or plastic, have a different number of blades, but the replacement process remains the same. over, this procedure is similar for the equipment of different manufacturers, be it Carver or Huter, but slight differences are possible. It is quite easy to change the knife on the trimmer if you follow the safety precautions and know the correct procedure, which can be found in the user manual. The entire replacement process step by step, as well as the method of self-sharpening knives, will be described in this material.

DIY trimmer coil repair

The trimmer, whether petrol or electric, is the only solution for cutting grass in hard-to-reach places that a wheeled lawnmower cannot handle. As a cutting tool in trimmers, metal knives or special fishing line are used, which is tucked into the trimmer coil. But, unfortunately, the trimmer heads become unusable over time during operation. Some malfunctions can be eliminated by hand, and some require a complete replacement of the mowing head.

How to remove the spool and replace the line

Trimmer owners, mostly beginners, find themselves in confusion, bordering on panic, when they need to change the cutting tool or line in the reel. Very often, when trying to unscrew the mowing head, users simply render it unusable, not suspecting that it is unscrewing in the opposite direction. To prevent this from happening, if you need to replace the tool, we recommend that you read the step-by-step instructions below.

• Stop the mowers engine or power off the trimmer before placing the line into the spool to avoid injury from accidentally starting the cutting tool.
• Unscrew the nozzle attached to the gearbox shaft. To do this, the shaft must be fixed by aligning the holes on the washer and on the axle, and inserting a metal rod or screwdriver into them.
• Unscrew the nozzle. You should be aware that the thread on the shaft is left-hand. Therefore, turn the trimmer coil to the right, that is, clockwise.
• Disassemble the mowing head. Most often, the head cover is attached to the clips. To remove it, you will need to sink these latches into the case, squeezing the edges of the cover. If your trimmer has a semi-automatic mowing head with a button on the bottom, then the disassembly of the attachment should be done carefully, since you can lose the spring, which sometimes flies out when the cover is removed.
• Cut off the required amount of line. Usually its length is 5 meters. Use a cord of the same diameter as indicated in the instructions for the tool. It is not recommended to exceed the maximum line diameter as this will result in increased engine stress and higher gas mileage.
• Find the midpoint of the line by folding it in half. You will have a loop.
• Special grooves are cut inside the coil (there may be holes). Insert a loop of line into this groove.
• Wind the line around the spool by turning it counterclockwise. It is necessary to fill in the cord as evenly as possible, the turns should lie down without overlap and with good tension. When winding is finished, leave free ends of the line about 20 cm long and fix them in the grooves on the sides of the reel.
• Assemble the mowing head. Be sure to insert the spring and washer (if applicable) before final assembly of the accessory. Place the spool in the body and thread the ends of the cord through the holes or eyelets.
• Put on the cover and secure it with the snaps.
• Screw the adapter back onto the gearbox shaft, also securing it with a screwdriver. You will need to twist the trimmer coil to the left (against the arrows).

Major coil faults

Trimmer users and lawn mowers often encounter a problem with the semi-automatic mowing head. Coil malfunctions can be as follows:

• The line does not lengthen automatically;
• The cord spontaneously comes out of the reel.

Line does not lengthen automatically

If the line does not lengthen when you lightly hit the trimmer button on the ground, then the reasons for this may be the following.

Option 1. a bite has occurred, i.E. Clamping the cord between turns. This problem usually appears if the user has been winding the line on the reel unevenly, with intersecting turns, or winding it with insufficient tension. In the latter case, when the mowing head rotates at high speeds under the influence of centrifugal force, the cord begins to tighten, as a result of which inter-turn clamping of the line is possible. To fix the problem, you will have to disassemble the coil on the trimmer and rewind the cord correctly, that is, in even turns with good tension.

Option 2. too short ends protrude from the head. The line may not come out when hitting the ground if the ends sticking out of the head are not long enough (short). In this case, the centrifugal force is not enough to stretch the line. Therefore, it is required to stop the unit (turn off the engine or disconnect the trimmer from the mains) and pull the line manually, after pressing the button.

Option 3. the line is soldered inside the mowing head. This causes the coil to lock and not spin when the button is pressed. Basically, this happens for several reasons: poor quality of the cord, overheating of the coil during prolonged operation of the unit, hitting the line against hard objects.

• In the first case, third-party cord can be made of low-quality and low-melting materials that cannot withstand mechanical and temperature stress. Therefore, you should give preference to "branded" lines.
• But, if you nevertheless purchased a fishing line of unknown quality, and it is often soldered during operation, then you can follow the example of some users who, after filling the cord into the reel, moisten it with either silicone grease (from a can) or mineral oil. This procedure greatly reduces the likelihood of the coils of the fishing line being soldered together.
• Also, the line can become soldered if it strikes a hard object (stone, fence, dry branch, etc.) during mowing. As a result, it stretches slightly and is pulled back into the head at high speed. From friction, the cord heats up, and its turns stick together. The only thing that can be done to eliminate this malfunction is to open the trimmer spool and rewind the line.

Trimmer coil device

Trimmer mowing heads come in a variety of designs, both simple and complex. The picture below shows an exploded view of the Husqvarna (Husqvarna) semi-automatic trimmer head.

This type of head is present on most lawn mowers and trimmers such as Stihl (Stihl), Patriot (Patriot), Champion (Champion), Bosch (Bosch), Huter (Huter) and others. The device of the mowing head is quite simple. It includes the following details:

• Mowing head base;
• Button for semi-automatic cord feed;
• Spool (spool) into which the line is tucked;
• Spring;
• Eyelets. through them the line comes out;
• Trimmer head cover;
• Line (cord).

There are also simpler trim heads shown in the following photo.

All these attachments do not allow changing the length of the line in a semi-automatic mode (after pressing a button). If the cord breaks, you have to stop the mower and change it manually.

The cord lengthens spontaneously

There are times when the trimmer user notices a very fast line flow. At the same time, he never hit the ground with the button to lengthen the line. The reason for the fact that the line spontaneously lengthens, being cut on a special knife on the casing of the device, may be the absence of a spring in the mowing head. Often novice users of mowers, trying to load the line into the reel, forget to install the pressure spring in the head, or completely lose it when opening the cover, and in the future, do not even suspect of its existence.