How to make a speed grinder with your own hands
If you have an old angle grinder in your arsenal, do not rush to write it off. Using a simple electrical circuit, the device can be easily upgraded by adding to it the function of changing the frequency of turns. Thanks to a simple regulator, which can actually be assembled with your own hands in a few hours, the functionality of the device will increase significantly. Reducing the speed, the grinder can be used as a grinding and sharpening machine for various types of materials. There are new opportunities for the use of additional attachments and accessories.
- 1 Why is the Bulgarian low revs?
- 3 How to assemble a regulator with your own hands
- 3.2 Scheme of the disciplineVideo: soft start plus and engine speed control
- 4.3 Features of mounting the finished unit
- 5 User manual for the device
- 5.1 Video: a homemade speed controllerComrade LBM
Why low speed grinder?
The integrated disk speed control feature allows you to delicately handle materials such as plastic or wood. At low revs, comfort and safety is increased. This function is especially useful in electrical and radio installation practice, in car-care centers and restoration workshops.
In addition, among professional users of power tools there is a strong opinion that the simpler the device is, the more reliable it is. And additional service "stuffing" is better to bring out of the power unit. In this scenario, the repair of equipment is greatly simplified. Therefore, some companies specifically produce remote individual electronic regulators that are connected to the power cord of the machine.
Speed controller and smooth start-up - what are
Used in electromechanical instruments, the design of which uses a collector motor. Help reduce the wear of the mechanical part of the unit during start-up. Reduces the load on the electrical elements of the mechanism, putting them into work gradually.
As studies of the properties of materials have shown, the most intensive development of friction nodes occurs during an abrupt transition from a state of rest to a fast movement mode. For example, one start of an internal combustion engine in a car is equal in terms of wear of the piston group to 700 km of run.
When the power is turned on, there is an abrupt transition from the state of rest to the rotation of the disk at a speed of 2.5–10 thousand revolutions per minute. Those who worked with the grinder are well aware of the feeling that the machine is simply “breaking free”.It is at this moment that an overwhelming amount of damage occurs associated with the mechanical part of the unit.
The stator and rotor windings are also under pressure. The collector engine starts in short circuit mode, the electromotive force is already pushing the shaft forward, but inertia still does not allow it to rotate. There is a jump start current in the coils of the motor. And although they are constructively designed for such work, sooner or later there comes a moment( for example, during a voltage surge in the network) when the winding insulation does not withstand and an interturn lock occurs.
When the soft start and change engine speed circuits are included in the tool's circuit, all the above problems automatically disappear. Among other things, the problem of the “failure” of voltage in a common network at the time of launching a hand tool is being solved. This means that the refrigerator, television or computer will not be exposed to the danger of "burnout".And the automatic circuit breakers on the meter will not work and turn off the current in the house or apartment.
The soft start scheme is used in the middle and high price grinders, and the speed adjustment unit is mainly used in professional angle grinders.
Speed adjustment allows the grinder to process soft materials, perform fine grinding and polishing - at high speed, wood or paint will simply burn.
Additional wiring diagrams increase the cost of the tool, but increase the service life and safety level at work.