How To Attach The Disc To The Trimmer

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.

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:

How To Attach The Disc To The Trimmer
  • 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:

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.

How to attach a saw blade to a 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 the 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.