Angle grinder gearbox lubricants: how to change, what to lubricate with and when to change it
Maintenance of the angle grinder (angle grinder, or angle grinder) includes the renewal of lubrication in the gearbox. Angle grinder grease is one of the necessary consumables. At least once a year you have to renew it.
Care should be taken in choosing gear lubricant for the gearbox, or the mechanism could malfunction. The gearbox of an angle grinder is too important to let it run roughshod over.
The role of the lubricant and its characteristics
A distinctive feature of the angle grinder is the gearbox, which consists of gears that have a helical structure. This node is subject to considerable load during operation and is subject to more wear than other gears. The rotor of the angle grinder generates a torque that travels from the small bevel gear to its large counterpart. The last gear has a shaft on which the working tool (mill, emery wheel, brush) is mounted.
As it moves, the teeth of the gears friction against each other increases in temperature. And that leads to weakening of the metal and to early wear. To prevent negative consequences, special compounds are injected into the rubbing nodes, which significantly reduce deformation and prevent parts from heating up intensively.
Lubricant for gearboxes of power tools must have the following parameters:
- Its viscosity must not exceed 800.
- The tensile strength of 120 pascal.
- The compound must be in the refractory category (above 100°C).
- have water repellent properties;
- stick firmly to the parts;
- Do not cause corrosive processes;
- do not contain mechanical additives.
But in addition to the gearbox, the angle grinder has two kinds of bearings which also need to be lubricated. One helps the electric motor. The other serves as a support for the spindle of the big gear in the gearbox. These bearings operate in different conditions and need different formulations of oil.
Lubricants recommended by foreign tool manufacturers
Foreign manufacturers of tools, including angle grinder, recommend specially designed ointments as lubricants for grinders.
One common foreign lubricant is the one marked MoS2 NLGI 2 ISOL-XBCHB 2 DIN 51825-KPF 2 K-20.
- MoS2. indicates the filler material, in this case molybdenum;
- NLGI2. indicates second viscosity grade;
- ISOL-XBCHB 2. belonging to ISO standards;
- DIN 51825-KPF 2 K-20. grease made to German DIN standards;
- The numbers 51825 mean that the grease is a type K.
Lubricants produced with such characteristics are quite expensive. There are imported, less expensive lubricants on Russian market.
Every tool manufacturer, be it Bosch, Makita, Hitachi, DeWALT, Metabo, RedVerg, Interskol, E256, LEPSE, recommends their lubricants. It is the manufacturer’s policy. They insist that when performing maintenance, the lubricants used are those specified in the instructions. over, non-compliance with these recommendations does not allow warranty repairs.
Makita angle grinder gear lubricant is available in tubes. Its high cost is commensurate with its high quality and long service life.
What kind of grease can be used for joints?
NLGI 2 consistency lubricants with additional extreme pressure additives in the form of molybdenum disulfide particles MoS2 are used for ball joints. This grease prevents weld friction and accelerated wear due to shock loads and ball travel in the metal guide of the joint body.
Snowplow manufacturers recommend using only gear oils. Do not use “Lithol” and similar inexpensive liquids as grease, because they do not provide adequate protection and freeze at low minus temperatures. The grease must have the following properties. Be frost-resistant.
The correct process for stuffing grease into angle grinders
Filling grease into the units of angle grinders has its own rules. It is necessary to know not only the order of its application, but also how much and where to put it.
When to change the grease in the angle grinder
Lubricant on the angle grinder is changed according to the maintenance plan of the tool, when replacing the failed gearbox parts or rotor bearings.
Old grease has a dirty, dark color. This is due to foreign metal particles or dust.
How to properly remove old grease from an angle grinder
Old grease must always be completely removed, regardless of its color. There must be no traces of old grease on the parts and no particles of broken parts in the housing cavities.
Old grease can be removed using a variety of flushing liquids used by motorists to wash the engine and parts. At home, it is recommended to use kerosene or a solution of kerosene and gasoline.
All parts and their cavities must be thoroughly cleaned and dried.
Lubrication of the angle grinder gearbox
New grease is mixed well before application and applied in a thin layer. The bearings are lubricated by packing. If grease is in a plastic tube, the neck of the tube is placed against the side of the bearing cage and pressed out until it flows out the back side.
How much grease should be used when replacing in the gearbox of an angle grinder
If the amount of grease in the bearings is controlled by the grease flowing out from the back, then a certain amount of grease is put into the gearbox of the angle grinder. Excess grease will leak out during operation. A small amount of grease does not ensure proper functioning of the gearbox.
Leave as much lubricant in the gearbox as is needed to cover the gear teeth.
For guidance, apply as much lubricant as is needed to fill a little less than half of the gearcase cavity.
Check that the grease is properly applied to the gearbox of the angle grinder
Control the amount of accumulated in the gearbox grease by testing the assembled angle grinder for a short time at idle.
If the gearbox begins to warm up, and there are signs of grease leakage from the seals and gaskets, then the conclusion is clear. You have relubricated. Open the gearbox housing and remove the excess grease. Any excess grease will be deposited on the gearbox housing covers. Insufficient lubricant in the gearbox is indicated by increased gearbox noise.
With prolonged use of angle grinder grease in the gearbox is distributed on the walls of the housing and from external influences loses its properties.
After opening the gearbox cover, carefully inspect the condition of the lubricant, the profile of the gear teeth. If you know how, check the contact patch of the gears.
The presence of dry or dried lubricant particles in the gearbox area or on the housing indicates that it is time to change the lubricant.
Gearbox lubricant for angle grinder. selection, application
Any power tool has a heavily loaded mechanical part, on the serviceability of which depends the performance of the whole device. As a rule, it is a gear reducer, which in an angle grinder (in common parlance. angle grinder) also changes the angle of rotation axis.
Any moving mechanism needs to reduce friction, and the lubricant for the gearbox of the angle grinder also contributes to the cooling of the unit.
The owner of a home tool is interested in the fact that the device worked long enough and after the warranty period, when the breakdowns can be eliminated at the expense of the manufacturer (or store). For this, the product must be properly and timely maintained.
Get Another Angle Grinder
Why do you need grease in the gearbox of an angle grinder??
From a technical point of view, the gearbox of an angle grinder is not too complicated. Two gears and shafts:
- leading is located on the shaft of the electric motor, in 90% of cases without transitional steps, it is connected directly;
- the driven one is a crown of teeth connected to the shaft to fix the working disc.
Shafts rotate in support bearings, which can be with a pressed cage (the grease inside, laid in the factory), and with an open cage. In the second case, lubrication can be changed and laid down during maintenance.
Gears are permanently engaged and run at variable speeds and loads. As a result, pressure occurs on both sides of the tooth with the same intensity. If a gearbox and bearings run dry, the metal will wear out very quickly and backlash will occur.
- First, there will be an increase in operating noise, which will increase in proportion to the wear.
- Tooth misalignment can lead to jamming of the gearbox mechanism.
- Then, each time the backlash occurs, the teeth bump into each other.
- From overheating caused by increased friction, the gear metal will lose strength.
- The case will end with the breakage of one or more cogs, and the failure of the tool.
Unpleasant finale? And all you had to do was spend some time and money on consumables and lubricate the gearbox of the angle grinder.
In addition to its main purpose: reducing friction, the grease acts as a heat conductive paste. Gears get hot and only the metal gear housing can dissipate the heat. Since oil has a high thermal conductivity, the temperature effectively dissipates on the outer walls of the tool.
How to service the gearbox of an angle grinder?
The lubrication intervals can be found in the service instructions, but this is quite arbitrary. You can never calculate the number of operating hours per service interval.
That’s why we recommend that you change the lubricant at least once a year if you use your machine a lot. It is not complicated at all. It is enough to unscrew the 4 screws on the gearbox housing, remove the old grease and put in fresh grease.
Do not wait for unusual noises to occur. If this happens, it means that the mechanism is already worn.
How to lubricate the gearbox of an angle grinder?
To reduce friction, use the grease for the angle grinder recommended by the manufacturer. As a result, we get a situation familiar from servicing a car in dealership service stations: only the brand specified in the maintenance booklet.
As long as the tool is under warranty, the service center performs maintenance exactly according to this recommendation. And what grease to use for the gearbox of an angle grinder, if you perform routine work yourself?
Of course, only products with the manufacturer’s logo of the angle grinder are specifically marked.
Grease of the same name for bolsters is ideal for maintenance, but its cost is usually higher than analogues. For example, grease oils for car gearboxes work under loads that are many times higher than the working conditions of the angle grinder.
And the cost of such product can be lower. In addition, if you have a car, for sure there are oils for its maintenance. So why buy another tube when you can just use a ready-made grease?
For the right choice it is enough to look at the characteristics, and compare them with the requirements for the lubrication of the angle grinder:
- high adhesion because there is a possibility of centrifugal splashing of lubricant from the driven gear
- water resistance: the angle grinder is often used outdoors, it is possible for moisture to get into the gearbox
- Resistant to emulsion formation;
- high drop point, high speed again: heated oil can splash from the work surface
- stability of parameters at high temperatures (this characteristic is more important than the ability to work in the cold);
- ability to bind abrasive particles that enter the gear housing.
The last characteristic is especially important if you use an angle grinder to grind stone. Abrasive dust is a major problem for the gears of bolt cutters and causes premature wear.
Therefore, if the tool is operated in a dusty environment, grease should be replaced more often and the gearbox cavity should be completely flushed.
This video details what lubricants to use to maintain the angle grinder’s gearbox
The alternative to brand-name grease
If you do not have a suitable automotive grease in your garage, and you do not want to spend money on “Makita” or “Bosch” (especially since these plants do not have oil refining facilities anyway), go to the well-known universal manufacturers.
Castrol, Mobil or Huskey offer good formulas. Of course, you should not buy a jar weighing 1-4 kg, for two or three service angular grinder is quite enough 100-250 ml.
The use of gear lubricant for the maintenance of angle grinder
The angle grinder, like other tools used in household and professional activities, requires regular maintenance. Efficient operation and a long service life are ensured by timely maintenance.
Angle grinder grease is a key component in maintaining the device. In order to improve performance, the right formulation should be chosen.
Rules of replacement
The main module of the angle grinder is the gearbox. It assumes the bulk of the load during operation. It consists of helical gears, which transmit the torque from the rotor to the working element. Angle grinder gearbox lubricant provides friction reduction in the gears. Also contributes to reducing the temperature that occurs during operation.
When to replace the lubricant? During operation, the lubricant is dispersed on the sides of the gear unit housing. After a short time, it begins to dry out and lumps are formed. Clumps can accumulate dust and metal particles generated during operation. If during disassembly of the angle grinder, lumps are found, then you need new grease for the gearbox of the angle grinder.
There are situations when it is necessary to replace parts of the angle grinder gearbox or rotor bearing. In this case it is necessary to disassemble the unit. Accordingly, the lubricant layer will be removed. New material is applied instead.
The gearbox of the angle grinder warms up during long periods of work. Accordingly, the coating used also begins to warm up. Lubricant becomes liquid when heated and may leak. As a result there is little lubricant left inside. This can be seen by examining the gears. They should have a thick layer on them. Thus, if the lubricating coating is small, it must be replaced.
Properties of the lubricant
Lubricating coating for gearboxes is characterized by the following properties:
- The viscosity is no more than 800 Pas;
- The droplet drop temperature should not be less than 120°C;
- strength is at least 120 Pa;
- The absence of mechanical impurities;
- Corrosion resistance;
- High melting point;
- water repellency.
It is necessary to choose a lubricant that does not contribute to the formation of seizures in the areas of contacting parts.
When selecting a coating, it must be remembered that the lubricating coating for gearbox bearing parts is not the same as the lubricating coating for the motor bearings.
Many people are interested in the question. how to lubricate the gearbox of angle grinder in order not to damage the tool and increase its efficiency. These types of lubricants are possible:
Angel Grinder repair and greasing | grinder replace gear 6-100 by knowledge king
Many tool manufacturers strongly recommend the use of a suitable lubricant for maintenance in order to avoid negative consequences during operation. If you use a composition of another manufacture, the tool is not subject to warranty repair.
Many people may find it expensive to lubricate a gearbox with a manufacturer’s compound. After all, the cost of such materials is quite high. In addition, there are manufacturers who do not produce lubricants.
In this case you can buy the grease for CV joints, which can be found in wide assortment on the shelves of auto shops. This material allows to achieve positive results in operation. And a lot of people use this kind of lubricant. However, it is worth noting that this option is the worst, compared to the first.
If you choose grease or lithol as a lubricant, there is a risk of rapid tool breakage. This is because these substances are not intended for use at high temperatures and high friction. Therefore, after some time problems may arise in the work of the tool.
Thus, the optimal lubricant for the angle grinder is considered to be the one that corresponds to the brand of the tool manufacturer.
Stages of the lubrication process
Lubrication can be done in special workshops or by yourself. When performing lubrication by your own efforts, remember that a lubricant that does not match the brand of the tool can cause tool breakage. The process of treating with new lubricants involves the complete removal of the old layer of grease. parts and housing walls must be free of residues of the old coating.
Steps for lubricating the angle machine gearbox
- disassemble the angle grinder;
- wash with kerosene or a solution of kerosene and gasoline on the sides and cavities of the gearbox
- dry the washed parts;
- stir in the new lubricant;
- apply a coating to the bearings and cavities;
- assemble the tool.
During application the question arises: how much grease is needed? Applying large amounts of lubricant will cause excess to leak out during operation. With a small content, the functioning of the gearbox will be difficult and lead to rapid failure. Hence how much material is placed in the housing so that the gear teeth are hidden beneath the surface of the layer applied. Approximate coverage of gearboxes angle grinder is less than ½ of the volume of the whole gear.
Checking the accuracy of application
Lubrication of the angle grinder, namely its abundance, is checked in idle mode during a test run for a short period of time. After start-up, the gearbox begins to warm up. If, when the gearbox is warmed up, some of the lubricant leaks out, it is necessary to disassemble the tool again and remove the excess.
If you notice signs of rattling or noise after a short period of idling, increase the amount of grease.
Getting quality grease with your own hands
If you want to use a good lubricant composition of the gearbox angle grinder, and there is no possibility to buy it, then you should make it yourself on the basis of grease for C.V. joints. Do not forget that the material used should have good adhesion.
Situations where there was an urgent need to lubricate the elements of the angle grinder, not uncommon. And, as luck would have it, there is no way to get a suitable lubricant for this purpose. Then the owner can try to make a remedy with his own hands from available materials.
In order to provide the required level of adhesion, a lubricant for CV joints is taken as a basis. In addition to its excellent penetrating properties, it can also be used for operation in conditions
- considerable loads;
- high humidity;
- temperature fluctuations in a wide range;
- significant heating;
- exposure to solid contaminating particles.
Adding oil MS-20 is recommended to thin the material and obtain the desired consistency for the gearbox. The liquid is added to the base gradually, preferably in drops, while constantly mixing the resulting mixture with a mixer.
No less effective is the use of homemade material based on “Citiam-221” with the addition of TAD-17.
And what kind of gear lubricant do you use?? Have you ever made your own lubricant?? Please share your experiences with us.