That the lawn pleased you with a pleasant color and was healthy and well-groomed, it is necessary to sharpen the knife periodically. How often you need to sharpen a knife, it is very difficult to say for sure, the time between sharpening is different for all lawns, knives and lawn mowers. It is enough to put the question in another way: “how often do you need to sharpen a kitchen knife?”, There is only one answer: “as soon as you think that it has become dull”. The same goes for lawnmower knives.
How to sharpen a lawn mower knife:
3. Sharpening machine
Some more craftsmen sharpen knives with an angle grinder (angle grinder), but we strongly recommend this, for security reasons.
To sharpen the knife, you must first remove it. The knife is removed quite easily. For this it is necessary put the mower in the service position Decks, tilting back to the handles, previously loosening the mounting bolts of the handle.
note that do not tilt the gas mower to the right side, towards the carburetor, as oil from the crankcase will enter the carburetor and cause undesirable consequences, such as contamination of the fuel system, sticking of the carburetor needle and may even be required lawn mower repair in the service center. Also, we do not recommend tilting the mower to the left side, towards the muffler, since when cranking the shaft there is the possibility of oil getting from the crankcase into the muffler, which can also have not very pleasant consequences, such as intense white smoke from the muffler.
So, turn off the knife counterclockwise, in 99% of lawnmowers the knife is turned off exactly counterclockwise. Be careful and attentive, many lawn mowers are equipped with friction protective devices, do not lose the washers and bushings of the knife drive system. Try to remember the installation order of all elements.
Next is necessary clean knife from adhering grass and earth. Since excess grass we will interfere with further balancing.
Fix the knife for the convenience of sharpening, when using a file, or a donkey.
Need to sharpen a knife in the direction of the last sharpening, at an angle of 30 degrees from the horizontal mowing line. All knives for lawn mowers are sharpened from above, a flat platform remains below. You should not sharpen the knife on both sides, as we usually sharpen household knives, or sharpen it from below, as this can degrade the quality of cutting and collecting grass.
Sharpening length it is necessary to do 11-13 cm, for ordinary knives and 15-20 cm for mulching knives. You do not need to sharpen more, since this length is working, closer to the middle of the knife, grass is not cut, this is due to the frequency of rotation of the knife.
If this is not the first time you have sharpened a knife, remember that maximum depth, at which all the dynamic properties of the knife are preserved, is 10 mm. Do not sharpen a knife if the depth exceeds 1 centimeter, if you value the beauty and health of your lawn.
After you have sharpened a knife it is necessary remove excess metal on its back. With a slight enough movement, without effort, hold it with a file or a donkey.
Next you need balance the knife, to avoid unnecessary vibration of the mower. To make the correct balancing, you must have a special balancer for the knife of the lawn mower, but if you do not have it in the arsenal, you can use a conventional screwdriver, or an iron rod. We insert a screwdriver into the central hole of the knife, in the center, and if one of the wings slopes down, then we remove the excess metal from that side. We achieve a balance so that no wing of the knife outweighs.
Everything, the knife is ready for operation. Next, install it back, do not forget to install all the fasteners in place. If you have a torque wrench, then tighten the knife mounting bolt need with an effort of 51-68 N.m., or 5.2-6.97 kilogram-force meter. If there is no special key, then on the Internet you can easily find an article on how to translate these numbers into a simpler designation: hand. steelyard. meter pipe.
We wish you a pleasant mowing and a beautiful, healthy lawn.
And if you need knife sharpening by professionals, or lawn mower prevention, you can contact our service center, you can familiarize yourself with services and prices in the section of our website: lawn mower repair.
Video: Lawn Mower Gasoline How To Sharpen Knives
Creating a beautiful lawn and maintaining it in order is not an easy task. And to make it easier, you need a reliable assistant. a lawn mower. There are many good and different models on sale. And although everyone has the same purpose, in a number of parameters they differ from each other. Let’s try to figure them out.
What are lawn mowers?
By the way of moving lawn mowing machines are divided into:
- manual (trimmers) that are held in hand when mowing,
- wheeled hand, which you need to carry on the lawn,
By type of drive motor distinguish mechanical, gasoline and electric lawn mowers.
Mechanical Wheel Mowers easy to operate, it does not need electricity or gasoline, but significant muscular effort is needed. They are environmentally friendly, silent and allow you to adjust the height of mowing the grass. The cutting mechanism is a cylindrical knife driven by wheels. Such a tool is good for caring for a young lawn, as the low speed of rotation of the knife prevents pulling out grass with a fragile root system.
Mechanical Wheel Mower
And we will consider gasoline and electric lawn mowers below.
Hand Lawn Mowers (trimmers) fit for regular lawn mowing in a small area even with an uneven surface, as they can mow at any angle. The trimmer is a holder bar, at the lower end of which is a cutting device with fishing line. And with high power. additionally with a circular knife. The mower hangs on a belt on the operator’s shoulder, literally making it easier for him to work.
Trimmer can be equipped electric or gasoline engine. Electric is located on the lower or upper end of the rod, and gasoline. only on the upper.
A protective cover limits the mowing edge and protects the legs of the mower from injury. During operation, the left hand holds the handle of the bar (adjusting, if necessary, the height of mowing the grass), and the right hand holds the handle with the engine control button.
The main advantage of trimmers. the ability to mow grass in uneven areas and close to bushes and trees. But maintain the same mowing height at the same time will not work.
The electric trimmer is powered by a household power outlet. To his merits can include:
- light weight
- environmental friendliness (there are no exhaust gases and noise).
Disadvantages of the electric trimmer:
- binding to a network (outlet),
- the presence of a stable voltage,
- forever disturbing cable on the lawn
- low power.
And the cable itself has a limited length: you can’t squint far from home.
Battery Trimmer. the same as the electric one, but the engine does not work from the outlet, so you can mow at any distance from the house. This is his basic convenience. However, the mowing area is determined by the capacity of the battery.
The gas trimmer is designed to work in large areas. Therefore, it is especially in demand by summer residents, and owners of country estates, and workers in urban utilities. However, working with it requires some preparation.
This type of lawn mower is distinguished by an enviable mobility, increased power and practicality. It can be used for mowing not only lawn grass, but also weeds and bushes. And professional models are able to cut stems up to one and a half centimeters thick.
However, even with a small fuel tank, such an assembly:
- weighs quite a lot,
- requires a mixture of gasoline with oil,
- pollutes the environment with exhaust fumes,
- makes a noise.
But it can work in any weatherat.
The convenience of mowing grass with a trimmer is determined by several points, and one of them is the location of the engine.
Trimmers engine bottom on sale a lot. Most often they rechargeable low power. They overheat quickly, so they require frequent interruptions in work. Protection against moisture and mechanical stress is poor. They cannot work on morning dew and immediately after rain, otherwise a short circuit may occur.
Trimmers engine top more practical, more balanced and more powerful, require less mowing effort, and therefore more comfortable in operation. They have good cooling (less overheating), and, therefore, greater performance.
Engine Top Trimmer
Among the trimmers with an upper engine, I especially want to highlight knapsacks. Their engines are secured behind their backs (like a schoolbag), which significantly reduces the load on the hands and much less restricts movement.
Knapsack petrol trimmer
A nice trimmer option is anti-vibration system. It allows you to reduce the vibration load on the shoulders and hands, protects the arms and back of the mower.
Powerful gas trimmers to reduce the burden on the hands equipped with ergonomic handle, similar to a bicycle wheel. On the right handle are buttons to control the operation of the tool. When buying a trimmer, make sure that the handle and button layout on it are comfortable for you.
Comfortable bicycle handle