2023 Author: Philip Bishop | [email protected]. Last modified: 2023-08-25 07:54
- Design features of LBM Sparky
- Sparky grinder repair tool
- Mechanical malfunctions of Sparky grinders
- Gearbox repair
- How to change gears in a Sparky gearbox
- How to replace bearings in a gearbox
- Malfunctions of the electrical part of the Sparky grinder
- Repair of control circuits of the grinder Sparky
- Rotor repair
- How to replace bearings on the Sparky grinder rotor
- Stator repair
- The procedure for disassembling the Sparky grinder
- The choice of lubricant and the procedure for applying it to the gearbox of the Sparky grinder
- Helpful hints.
- Sparky grinder repair video
The Russian consumer prefers the Sparky grinders not only because of the high operational convenience, but also the ease of repairing the Sparky grinder, favorable price-quality ratio, the presence of a speed control device, an anti-vibration handle, and an original protective casing.
Sparky grinders are available in three classes: small, medium and large. The class is determined by the dimensions. In the small class, 15 (fifteen) models are produced, the weight of which ranges from 1.2 kg to 2.4 kg. The middle class is represented by three models, the weight of which lies in the range of 2.5… 3.3 kg. In a large class, 10 (ten) models are produced, the weight of which reaches 6.3 kg. The recognizability of the Sparky grinders is given by a bright appearance: the housing is purple, the gear housing is bright red or silver.
Design features of LBM Sparky
The features of the Sparky grinder include:
- Multifunctional switch, which provides for the function of blocking the spontaneous start of the grinder;
- The body is double insulated;
- There is a soft start device, setting and maintaining a constant rotor speed;
- The design of the brush holder does not allow dust to linger and carbon brushes get jammed;
- The grinder uses automatically switching off carbon brushes;
- Complete with anti-vibration handle;
- Application of a protective cover with the possibility of quick installation and removal;
- The gear housing is made of durable, lightweight magnesium alloy;
- Intelligent ventilation system for improved cooling performance.
Sparky grinder repair tool
In order to perform a high-quality repair of a Sparky grinder of any modification, one cannot do without a high-quality and necessary tool. There are no special requirements for the tool.
Since bearings are used in the Sparky grinder, it is advisable to use pullers to remove them. A Russian craftsman can do without pullers, but at the same time he cannot perform high-quality repairs.
Repair of Sparky angle grinders is conventionally divided into electrical and mechanical repairs.
A tester is needed to repair the electrical part. If you have the opportunity to buy or rent a device for detecting short-circuited loops, we recommend using a simple IK-2 probe. Such a device allows you to find an open or short circuit of turns without dismantling the electrical parts. It is indispensable for the repair of the rotor, stator grinder.
Prepare screwdrivers of various sizes. You can't do without wrenches.
Of the auxiliary materials, you will need grease for gearboxes and bearings, rags or cleaning material, washing liquid. It is recommended to use a mixture of kerosene and gasoline at home.
If you plan to repair the rotor or stator of the angle grinder, you will need varnish or paint to impregnate the windings.
Do-it-yourself grinder repairs must be performed in a prepared, well-lit workplace.
Mechanical malfunctions of Sparky grinders
All malfunctions in grinders are divided into mechanical and electrical.
Mechanical faults include:
- Destruction of the gearbox, failure of the gears;
- Seizure or destruction of bearings;
- Destruction of the grinder gearbox housing.
The reducer of the Sparky grinder is a gear pair enclosed in a robust housing. Various tools are attached to the spindle of the driven gear, allowing you to work with metal, stone, wood.
Most often, a gearbox failure is associated with the failure of one of the gears. At the gear, a tooth is chipped or licked, the support needle bearing is destroyed. In addition, the support bushing or the needle bearing fails.
The design of the gearbox of the Sparky grinder of various models is slightly different depending on the power.
The driven gear in the gearboxes of the Sparky grinder is attached in two ways: by pressing or using a keyed connection. The keyed connection is most often used in low-power Sparky grinders. A small diameter ball is used as a key.
Repair of the gearbox of the Sparky grinder provides not only the replacement of a failed part, but also a change of lubricant.
In grinders with a power of over 1000 W, the driven gear is pressed onto the spindle shaft and is removed only with a press. But with a certain skill, this procedure can be performed without the use of a press. You just need to remember that caution and accuracy are the main success factors in doing this work.
Removing the driven gear is easy. It is necessary to unscrew the screws securing the housing cover, pull out the cover with the mounted bearing and spindle. Pull the spindle shaft out of the bearing. If the driven gear is attached with a key, then the retaining ring must be removed before the gear is removed. Some low power models use a small diameter ball as the key.
By removing the retaining ring, you can gently disassemble the key and release the driven gear. The gear is replaced when the percentage of tooth wear is exceeded. And this is determined only by the area of the contact patch of a pair of teeth. The contact patch is the main characteristic of the performance of a gear pair.
The drive gear in Sparky grinders is even easier to remove. On all Sparki grinders, the drive gears are attached to the rotor shaft with a key and are clamped with a nut with a right-hand thread.
To dismantle the pinion gear, the reducer must be removed from the stator housing. Always remove the carbon brushes that prevent the rotor from being pulled out before removing the rotor. The carbon brushes in the low power Sparky grinder can be obtained by removing the stator housing cover. To do this, unscrew the screw at the end of the housing handle and pull the cover.
In Sparky grinders of high power, the carbon brushes can be removed without disassembling the handle.
How to change gears in a Sparky gearbox
To remove the drive gear, it is necessary to clamp the freed rotor in claims, having previously laid a protective gasket. Choose a gasket of soft material to avoid damaging the rotor housing.
Using an S = 12 wrench, unscrew the nut securing the pinion to the rotor by turning the wrench counterclockwise. If you can't unscrew the nut the first time, pour VD-40 liquid into the threaded connection. Letting the liquid act for a while, try again to unscrew the fixing nut. This usually works.
When the nut is released, the rotor shaft can be pulled out of the gear housing. The drive gear is fixed to the rotor shaft with a key.
It is enough to remove the retaining ring, if provided in the design, pull out the key, as the gear is simply removed from the rotor shaft.
Remember the golden rule. The gears in the gearbox always change in pairs.
By the way, in Sparky grinders of low and high power, there is a possibility of a gap between the gears in the gearbox using special shims.
How to replace bearings in a gearbox
One of the gearbox malfunctions in the Sparky grinder is manifested in the occurrence of backlash in the spindle shaft. This can occur both in the event of a failure of the shaft bearing and the support needle bearing. The appearance of play indicates the destruction of the needle support bearing in the gear housing. It is especially difficult to remove the outer cage of the needle bearing from the seat in the gear housing.
The easiest way is to remove the clip from the housing using a machine tap of a suitable diameter and a screwdriver. Hold the tap in the screwdriver chuck and try to screw the tap into the bearing race. When the tap reaches the bottom of the socket, it will begin to lift the clip.
Bearings are removed from the spindle shaft using a puller or folk remedies.
Sparky grinders of low power up to 1000 W use a needle bearing of the NK0709 type. Some low power models use copper graphite bushings.
The spindle shaft of Sparky grinders up to 1000 W rotates in a 6300-2RS type bearing.
In the gearboxes of Sparky grinders over 1000 W, more powerful bearings are used: support needle type NK-1212, sleeve bearing type 6206-2RS. Bushings in high power grinders are not used.
Malfunctions of the electrical part of the Sparky grinder
With proper use of the Sparky grinder, the uptime can be several thousand hours.
Basic rules for the trouble-free operation of the power tool:
- Timely replacement of carbon brushes;
- Regular grease change;
- Prevention of using the tool under heavy loads;
- Prevention of overheating of the tool;
- Using the tool as directed.
Repair of control circuits of the grinder Sparky
Control circuits of grinders of various capacities have their own characteristics. In grinders with a power of less than 1000 W, the ARV-2114 Defond switches are used, an electronic device for regulating the spindle speed.
Photo of the control circuit diagram
Control circuits of Sparky grinders over 1000 W are equipped with KD10 switches, a capacitor, carbon brushes with a contactor, which are part of the brush holder.
Most often, Sparky grinders fail for the electrical part due to a break in the supply cable. This occurs where the cable enters the tool and plug.
The second reason for the exit of the tool for the electrical part is wear or breakdown of carbon brushes. Carbon brushes should be replaced when the worn out brush is no more than 5 mm long.
The rotor of the Sparky grinder fails due to overload and overheating, wear or untimely replacement of carbon brushes, breakage or short circuit of windings, destruction of the collector or destruction of bearings, leading to rubbing of the rotor against the stator.
The rotor is a complex part, which is not easy to repair without certain skills, skill and equipment. It is preferable to buy a new rotor or go to a workshop if you see a rotor for the first time. If you want to repair the grinder rotor with your own hands, refer to the materials already posted on the site. But the breakdown of the rotor is associated not only with the failure of its electrical part. Most often, the cause of its output is the destruction or jamming of bearings. The rotors of the Sparky grinders are equipped with two bearings. One on the fan side and one on the collector side.
How to replace bearings on the Sparky grinder rotor
On grinders with a power over 1000 W, the following bearings are installed on the rotor.
Bearing near manifold type 6000-2ZP63LDS18.
Fan side bearing type 6202 ZTNHP63LDS18.
Grinders up to 1000 W are equipped with such bearings.
Bearing near manifold type 6262ZP6E LDS18 SKF
Fan side bearing type 6092ZP63LDS18.
Bearing failure is indicated by difficulty in scrolling, jamming, discoloration to dark, destruction of the bearing race. The bearings are removed using pullers. The operation is not particularly difficult and can be performed by any user.
The stator design in Sparky grinders is no different from the stators of other grinders. Repair consists in finding the causes of the breakdown and rewinding. To determine an open or short circuit in the stator windings, it is preferable to use a tester and a short circuit detection indicator.
Stator rewinding is much easier than rotor repair and can be done at home.
The stator repair algorithm is simple and has been presented more than once on the pages of our site. To wind the stator on your own, you must not only be able to correctly count the number of turns, their winding order, but also be able to properly soak the winding with varnish.
The procedure for disassembling the Sparky grinder
Regardless of the power of the Sparky grinders, the disassembly procedure is almost the same.
Disassembly begins with the removal of the carbon brushes. They are easy to reach when you remove the housing cover or protection on the brush holders.
The thing is that to remove the rotor from the stator housing, the carbon brushes prevent the rotor from being pulled out by rubbing over the collector lamellas.
In the next step, the gearbox housing and stator housing are disconnected. It is only necessary to unscrew the four screws securing the gearbox housing and the stator housing.
To disassemble the gearbox housing, remove the cover by unscrewing four screws. The driven gear shaft assembly is mounted in the gearbox cover. We have already examined the disassembly of the driven gear shaft assembly.
The electrical part is even easier to disassemble, since the number of parts in its composition is even less.
Carbon brushes are mounted in brush holders and fixed with special pressure springs. When taking out brushes for repairs, remember the places and directions of their installation. Brushes wear unevenly. And the angle of rotation of the rotor affects the wear of the brushes.
The choice of lubricant and the procedure for applying it to the gearbox of the Sparky grinder
The manufacturers of the Sparky grinder recommend using Liver T-0-1.00 kg grease for lubricating the tool. But it is allowed to use domestic lubricants specially developed for lubricating gearboxes of grinders. Today the choice of lubricants for grinders is quite wide.
In addition, high-quality grease for the grinder gearbox can be made at home.
You just need to take as a basis a lubricant that adheres very well to metal surfaces and
comes off with difficulty at high speeds. Scientifically, a base lubricant should have increased adhesion.
Automotive pivot joint grease is best suited as a satisfying base. Take the SHRUS-4 grease as a base.
Add TAD-17 grease to it with a syringe and mix thoroughly until you get the consistency of thick sour cream. It is better to mix the lubricant with a drill armed with a homemade mixer.
Apply as much grease to the gearbox housing as will fit in half the gearbox volume.
The grease is applied after thoroughly removing the old grease. To thoroughly and completely remove old grease, it is recommended to use a hair dryer, with which the old grease heats up and easily flows out of all hard-to-reach cavities
- After 700 hours of operation, check the condition of the carbon brushes;
- For any heating of the grinder body, service the tool;
- Better to change carbon brushes more often than to buy a new grinder;
- Monitor the condition of the lubricant and replace it if it significantly changes color;
- To reliably turn on the low-power Sparky grinder, periodically lubricate the power button lever with silicone grease;
- Listen to the sounds of the gearbox (a working machine does not make extraneous loud sounds);
- Check gear clearance often. When increasing it, use special shims. (There are three of them in the construction of the Sparky grinders);
- Do not skimp on grease or carbon brushes, the more often you change grease and install new brushes, the longer you will last;
- If the design of your Sparky grinder in the gearbox uses a copper-graphite bushing as a support bearing, replace it with a needle bearing of the appropriate size.
If you decide to purchase a grinder of the Sparky family, you will receive a quality tool that will bring you joy while working, but will create some problems during repair
Sparky grinder repair video
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