In everyday life, situations often arise when something needs to be sharpened. Electric sharpener with his own hands - this is the solution to many household problems with sharpening tools. It can be household items: knives, scissors or construction tools. Most often in this case it is necessary to grind drills, axes, shovels. It is difficult to work with a blunt instrument, the process is progressing slowly, a lot of energy is being spent. In this case, one cannot do without a special device, since not every tool can be sharpened with a bar manually.
Electric motor homemade machine for sharpening.
Elektrotochilo can be bought in the store, but you will have to pay an impressive amount for it. And it is possible to collect from improvised material, all the more so as the necessary men from time to time get into the hands of all the necessary materials. To adapt them for useful work is also not difficult. The result will be emery, not inferior to the store, but almost free.
Required materials and tools
For the manufacture of the device you need a little:
- electric motor;
- flange or trimming pipes and electrical tape;
- tap for threading;
- metal thickness of 2-3 mm for the manufacture of protective cover;
- bolts, nuts;
- rubber for lining.
Which electric motor is suitable
The main element, without which it is impossible to assemble a device, is an engine.
Commonly used motors from old household appliances. For example, from the Soviet washing machines "Siberia" or "Volga". The engines they reverse, have sufficient power and speed. On the shaft, you can install any necessary attachments.
Electric scheme of grinding grinder.
The number of revolutions per minute should not exceed 3000 in industrial conditions, and 1000-1500 is sufficient for home use. If rotating too fast, the emery wheel may break. For industrial work using grinding stones of great strength and special flanges. Home craftsman is unlikely to find such materials. High speed is needed not so much for sharpening, as for leveling and polishing the product. Again, for living conditions it is not useful.
Do not chase and for too much power. In the manufacture of the machine with their own hands the top bar - 400 watts. On average, the engines used by washing machines, whose power does not exceed 200 watts. To produce sharpening knives, hoes, drills, more than enough. Moreover, with such power, one does not have to fear that too much speed will develop. Therefore, it is not necessary to worry about the safety of the disc (and your own health).
For electrostatic suitable single-phase and three-phase motors. Both can be connected to a single-phase network. A capacitor may be required for proper connection. Asynchronous electric motors are commonly used.Back to table of contents
How to choose a flange
At first glance, everything is simple: the engine is taken, a sandpaper is pushed onto the shaft, the device is turned on into the network and starts to sharpen. However, at the stage of installing a grinding stone, a difficulty arises: the diameter of the sharpener, as a rule, does not coincide with the diameter of the shaft. Yes, and there is no thread, that is, to fix the emery is not possible. To fix this problem, you need a flange - a special part that is machined to the size of the shaft and the internal diameter of the abrasive disc.
To grind the flange, you have to use the services of a turner. In the electric drawing drawing, you need to specify the internal diameter of the grinding wheel and the size of the shaft. You need to specify in which direction the axis rotates. Perhaps the special flange is the only part that needs to be made to order. But it can be replaced by scrap materials.
The finished flange is mounted on the shaft and secured with a nut, washer and bolt. The nut will have to cut the thread. If the shaft moves clockwise, then left-handed thread should be used. When rotated counterclockwise - right. Compliance with this rule is strictly mandatory. With such threading, the nut will gradually tighten, and the circle will become more securely fixed. If you do the opposite, then the nut will gradually unwind. As a result, the sharpener may fall off the shaft. This is very dangerous, since it is unknown which way a rapidly rotating stone will fly. It can cause serious damage or injury.Back to table of contents
Analogue flange sharpened
However, not everyone has a familiar turner or suitable equipment. In this case, you can make an analog flange. The case will be more complicated, but the result is reliable.
In this case, you will have to use a sleeve system. For work, you need trimming pipes of the required length and suitable diameter. The gaps are eliminated using cotton insulation tape. If necessary, the sleeves are inserted into each other.
When winding tape must go very smoothly. If there are noticeable bumps, the disk will beat while rotating. The sleeves are selected in such a way that the inner diameter of the sharpener and the tube coincide. The ideal option would be the one in which the stone will sit on the sleeve without electrical tape is very tight, vnatyag. The winding will provide a tighter connection, the disk will not scroll on the pipe.
The system of sleeves is very firmly and tightly mounted on the shaft, but fixing with the help of bolts is necessary, since only it can ensure an adequate level of reliability and safety.
You can cut the thread yourself at home. For this you need a tap.Back to table of contents
Direction of work
Diagram of a universal converter.
Before proceeding to the manufacture of electrostatic, you need to see which way it will turn. The device, assembled from scrap materials, you can change the direction of rotation without much hassle. The engines that are most often used are taken from Soviet washing machines. And they are asynchronous. This means that when switching some windings, the direction of movement changes easily. Older motors have several conclusions (3 or 4) that will be useful if you change direction.
The direction will change if you change the leads of the starting winding. Such a technique can be useful for problems with threading, unscrewing nuts, etc.
You can do without a starting coil. Then it turns out work directly: the working winding simply turns on the network, you need to push the grinding wheel in the right direction, and it will begin to rotate.
To correctly determine where the working and where the starting winding, you will need a tester. The resistance level of the first is about 12 ohms, the second is all 30 ohms.Back to table of contents
Protective cover device
When all major parts are selected, care must be taken to comply with safety regulations.
Electric out of the generator.
It is no secret that when grinding metal products sparks fly. In order not to burn yourself, not to get injured, and also to protect the working surface from beatings, it is necessary to make a protective cover. You can make it from scraps of tin or metal. The optimum plate thickness is at least 2 mm. Iron can be screwed directly above the grinding wheel or fixed with a clamp. The shield will also reduce the amount of dust.
Additional safety when working will provide a folding canopy of plexiglass, which is attached to the casing and, if necessary, reclines.
Do not interfere and handcuff. When working, it is much more convenient to rest on it than to keep the part on weight all the time.Back to table of contents
When elektrotochilo collected, you can begin to install it. It is necessary to fix the sharpener very firmly and reliably, since when working there are large vibrations.
You can install the engine on the working surface using the same bracket that holds the motor in the washing machine. This will require bolts. The opposite side of the engine will rest on the angle. Thanks to this mount the motor will be in a horizontal position. At the corner you can install a rubber lining: it will reduce vibration.
Other installation methods may be used. For example, to fix the device on a stand, then it will be more mobile, since it will not be screwed to one place.
Everything, the machine is ready to work. You can sharpen various parts, tools, drills, etc.Back to table of contents
Safety rules at work
When working with machines it is very easy to get injured, and electric wastes are no exception to this rule, therefore, observance of safety precautions should be given special attention.
Types of flanges.
- Before work it is necessary to check whether the nut is tightened. Otherwise, the grinding disc can fly off and cause great damage.
- You should also make sure that the device itself is exactly and securely fastened. Otherwise, when vibrating, it may budge, fall, etc.
- It is necessary to ensure that the hands, in particular, the fingers, are located at a considerable distance from the rotating disk. Sharpening is fast, so there is a risk of injuring fingers.
- All work should be carried out with gloves and special glasses that protect the eyes from the ingress of chips.
- When working with dusty materials, you must use a respirator to protect the lungs from dirt and dust.
- Do not manually stop the rotating disk. This should happen, of course, after shutdown.
- Sharpen need on the end side of the stone facing the worker. No need to push the part under the casing or on the far side.
- You need to firmly hold the item to be sharpened, as they can fly out of your hands, break something, cut a person or break.
- You can not change the circle on the included device.
- It is necessary to monitor the state of the grinding disk. It must be changed when it detects cracks, large chips. The stone must be replaced in case of uneven abrasion and violation of symmetry. Such a sharpener will cause the entire structure to be loose.
Drill sharpening technology
Type drill diagrams.
The drills get dull very quickly, but it is a pity to throw them out. It is possible to sharpen tools using an electric grind. Someone is trying to make it a bar, but this procedure will take a very long time.
Sharpening the drill begins with the formation of cutting edges. The drill must be held parallel to the axis of rotation. The chips need to be removed until the reflection of light becomes noticeable. The same procedure must be repeated with the second edge. When grinding, you need to form the right angle. Drills, which are sold in stores, sharpened by 120 °. This is a universal indicator, but it may vary slightly. For work with soft materials, a more acute angle of 90-100 ° (wood, copper, plastic, aluminum) is used, for materials of medium hardness - 110-120 °, and for steel - 140 °
It’s impossible to get the necessary sharpness of the angle by eye, so you need to check the drill sharpening pattern from time to time. As a result of processing, the length of the edges of the drill should remain the same.
Then you need to handle the back surface of the edges. Their correct form is conical. You can control the process with the help of a washer. It is necessary to pick it up so that its diameter is 1/3 smaller than that of the drill.
The tapered edges need to make the rear corners, chips need to be cleaned so that the clearance between the washer and the drill increased by 0.2 mm.
When the edges are made, you need to act very carefully, otherwise you can blunt the cutting surfaces of the drill, so small strips should be left at the edges, the metal will be removed from them at the very end of the work, during finishing.
Elektrotochilo - a simple device that can be made independently. It is easy to assemble it, if there is a suitable engine.