DIY wood grinder. Do-it-yourself belt sander accessories. How to make a belt sander with your own hands. Tools and materials for assembling a grinder

During construction and repair work men often need to process wood, stone or metal. For quality work, it is advisable to purchase a tape grinding machine. But what to do when finances do not allow you to make such a purchase? To do this, it is enough to build a belt sander with your own hands.

Purpose of the belt sander

Wood is widely used in a variety of industrial organizations. Wood is used to make many kinds of details and products. In order to properly process a wooden blank and give it the appearance of a finished product, it is customary to use various equipment, including belt sanders.

Belt sanders are generally used for final stages production, when parts are subjected to finishing machining. Such devices are convenient to use in the manufacture of furniture and various consumer wood products. Depending on the material used, belt sanders work with wood or metal.

The main goals of using grinders for wood are the final leveling of the surface, bringing their level of roughness to the required level, obtaining even and smooth surfaces for wood products and wood-based material before veneering or after varnishing and other coatings. finishing materials, removal of local irregularities in the form of depressions and elevations, deburring and removal of local varnish and primer deposits, deburring, internal grinding and grinding of roundings.

Metal belt grinders work with various materials and formats that are popular in metalworking: plain and alloyed steel, non-ferrous metals in the form of square, round and flat billets. Grinding machines allow you to grind round timber and large diameter pipes rationally and with minimal time.

Depending on the type of processing and type of feed, belt grinders are intended for:

for sanding curved surfaces with free sanding belt;
for processing a flat surface with a fixed table, manual movement of the iron and table, as well as mechanized movement of the work table and manual movement of the iron;
for processing panel and bar parts, their ends and side edges;
for intermediate sanding of paint and varnish coatings.

The design of the belt sander

Belt grinding machines are produced by modern foreign and domestic manufacturers in a wide range. Grinding machine prices vary considerably. They also differ in their possible performance and their design. However, they also have something in common. They are united by the fact that absolutely all machines have an abrasive belt as a working body, which is most often connected into a ring and placed between rotating drums.

One drum is the leader and the other is the slave. This means that the first of them is equipped with a mechanical transmission, which is most often based on a belt drive, through which torque is transmitted to it from an electric motor. Any belt grinder is designed so that the speed of the driving drum, and therefore the speed of movement of the abrasive belt can be changed, providing different modes of surface treatment.

The abrasive belt can be positioned vertically or horizontally. In addition, there are equipment modifications on sale in which the working body is installed at a certain angle. The abrasive belt is mounted on a bed, on which the workpieces are usually located. Workpieces can be held manually by the operator, or with the help of special devices that facilitate the work of users and make the processing procedure more efficient and safe.

The machine table is made of metal sheets or thick boards. If the design provides for the manufacture of a table precisely from metal, then it will turn out to sharpen more complex products. The length of the working part of the belt grinder and the grinding belt itself primarily depends on the length of the products that will be sanded on the machine.

If the part has a shorter length than the working surface of the machine, then it will be much more convenient to process it, and the processing will turn out to be of better quality. For example, with a sanding belt length of 4.5 meters, wooden blanks can be easily processed, which have a length of 200 centimeters.

Belt grinding machines are divided into equipment with a fixed and movable work table and devices with a free belt. A special group is wide-belt grinding machines, in which the table, which is made in the form of a caterpillar, is also a feed organ. On machines with tables, the tape is placed horizontally, on designs with a free tape, it is installed in different ways.

Since a lot of dust is inevitably generated during the grinding process, all belt grinders are usually equipped with special powerful hoods that remove most of it during the very technological process. Grinding machines are powered by an electric motor, which has a power of about 2.8 kilowatts. With a high power motor, the normal belt speed reaches 20 meters per second.

Abrasive belts for grinding machines

The cutting tool of belt grinders is a sanding belt, which consists of a fabric or paper base and abrasive grains that are attached to it with adhesives. Abrasive belts are produced by two methods: mechanical and electrical. The first method consists in uniformly pouring abrasive grains onto the base, which is covered with glue, and the second method occurs in electric field, which orients the grains upwards with the sharpest edges to improve the cutting properties of the grinder.

Abrasive grains are poured onto the base in a bundle densely or rarely. The most effective is an abrasive belt with a rare backfill, when the grains occupy less than 70% of the area, because the wood dust generated during the grinding process is not able to clog between their grains. Can be used as an abrasive material natural minerals or artificial materials, which have high hardness, such as green and black silicon carbide, white and normal monocorundum, and normal electrocorundum.

For the purpose of gluing the grains, synthetic resins and skin glue are used. As a base, use a fabric such as calico and twill, or a special grade of paper. The size of the abrasive grains is indicated by a number that corresponds to the mesh size of the sieve in which these grains are retained, and is displayed in hundredths of a millimeter.

If you are interested in how to make a belt sander, then you should pay attention to the following sizes of grinding powders and abrasive grains and their classification: grinding grain - from 2000 to 160 microns, grinding powders - from 125 to 40 microns; micropowders - from 60 to 14 microns, very fine micropowders - from 10 to 3 microns.

Sanding paper is supplied to woodworking enterprises in sheets or rolls. On the non-working surface of the skin there is a marking with the specified characteristics of the skin and the manufacturer. For a belt sander, skins are used in rolls and cut into strips of a certain length and width. The length of the cutting tool is determined, depending on the method of its connection - overlap or butt at an angle.

The ends are cut off at a 45 degree butt joint and then glued onto a linen backing 80 to 200 millimeters wide. At one end of the tape, when lapping, abrasive grains are removed hot water for 80 to 100 millimeters, then the other end of the tape is applied to the bare base smeared with glue. Compress the connected ends and dry them using a special tool or size press.

Sheet skins are used for combined belt sanders. For grinding discs, it is customary to cut the skin in the form of a circle according to a pattern, the diameter of which is 60 - 80 millimeters larger than the diameter of the disc. Using a rectangular template, blanks are cut out for a bobbin. After cutting, they have smooth edges without tearing. The presence of unglued ends or seals when gluing the tapes can cause the tape to break prematurely.

The skin is cut for wide belt sanders into sheets according to a template that is made of plywood or aluminum sheet. The skin is cut in such a way that the edges are even, and the difference in the length of the side edges is no more than 1 millimeter. One of the beveled edges is cleaned, removing the abrasive at a width of 20 millimeters. The cleaned edge and the longitudinal edges are pasted over with a strip of tracing paper, which has a width of 40 millimeters, which protrudes beyond the edge of the skin by about 10 millimeters.

Lubricate the beveled edge with tracing paper with glue and keep it in the air, depending on the viscosity and type of glue. Then the beveled edges are connected and a strip of skin is applied to the junction, the junction is compressed and held in a press. Ready-made endless tapes are usually hung on special brackets and kept for at least a day in a dry room before being installed on a grinding machine.

The principle of operation of the belt grinder

The belt sander consists of a worktop with a working table for attaching the cutting tool. This table is fixed in different positions relative to the table top. The material for the countertop is usually laminated chipboard with a thickness of 25 millimeters. The working table on rollers moves manually or in the transverse direction by means of a mechanical drive on round guides that are attached to the calipers.

Above the table is a working tape, put on non-drive and drive pulleys. The sanding belt is tensioned and adjusted using a screw device with a pneumatic cylinder. Twin belt sanders have two identical sanding tools that are placed in series on the bed and have sanding belts that move towards each other.

Grinding is performed with the transverse movement of the working table and the longitudinal movement of a short iron, which presses the tape against the material being processed. Sanding belts are driven by an electric motor through a belt drive. Waste that is generated during grinding is captured by a dust collector, which is connected to the exhauster network.

When assigning a grinding mode, it is recommended, according to a certain roughness and properties of the material that is being processed, to choose the grit of the skin, the feed rate and the force of pressing the tape to the product. It is customary to choose the grain size of the skin, depending on the hardness of the processed materials and the required surface roughness. Clamping force and feed rate are interdependent quantities. With a small effort and a high feed rate of the skin, some places on the surface can not be sanded, with high pressure and low feed, burns and blackening of the material are possible.

Before installing the tape, check the quality of its bonding. Do not use incorrectly glued and torn sanding belts with an uneven edge. Using the handwheel, you can reduce the distance between the pulleys and put on the tape. The place of gluing is placed so that the outer end of the seam on the side of the abrasive is directed against the working movement of the sanding belt.

The belt tension can be adjusted by moving the tension roller for the belt grinder or the non-drive pulley. It is not advisable to stretch the tape too much, because this leads to its rupture. But the sanding belt slips over the pulleys at low tension and heats up very quickly. The tension force is set, depending on the strength of the base of the cutting tool and is determined by the arrow of its deflection with a slight pressure on it.

How correctly the tape runs can be checked by turning the pulley manually or briefly turning on the electric motor. The axis of the pulley, when the tape slips, is turned by the handle at a small angle and fixed with a locking device. After setting up the belt grinder, the dust extraction system is turned on, trial processing of parts is carried out and their quality is checked.

The manual feed belt sander can serve one worker. By moving the product relative to the cutting tool in the longitudinal direction, and turning the part around the axis, the operator sequentially brings into contact with the tape all the sections that form the surface to be machined. When slowing down or moving carelessly, grinding may form.

It is customary to grind individual parts of the part in several passes. It is possible to achieve high-quality alignment with the correct regulation of the pressure that is exerted on the ironing handle, and the speed of movement of the table and ironing. The pressure when approaching the edges must be reduced to prevent their grinding off. To increase the quality and productivity of grinding, small bars are placed on the table in a row, several pieces at a time.

Belt grinders with mechanical feed of products are served by two operators. One of them places the part on the conveyor, orients it along the width of the working table and directs the product under the clamping elements of the machine. Parts must not be moved sideways when being picked up by the conveyor.

It is not allowed to feed into the machine blanks that have an unequal thickness, and parts with gross surface defects. The feed rate and pressure of the clamping beam, as a rule, are not regulated during processing. The second operator takes care of receiving the finished parts and ensures that there is no unacceptable chamfering or grinding.

Production of a belt sander

The price of belt grinders from an industrial manufacturer is quite high, so when they are used infrequently, craftsmen involuntarily think about whether to buy equipment or not. An alternative to buying an expensive machine is to assemble it yourself. The main parts of the machine are the frame, rollers and engine.

The engine can be removed from the old washing machine. Cut out the bed from thick iron measuring 500 by 180 by 20 millimeters. Cut one side evenly milling machine for metal, it is required to mount the platform with the motor. Dimensions of the working platform - approximately 180 by 160 by 10 millimeters. Make a markup and drill three holes in the end face of a flat-cut bed. It is necessary to pull the platform to the frame with three bolts.

Remember that the longer the desktop is, the more options you will get when choosing a technological method for grinding and processing the product. If the length of the workpiece is less than or equal to the length of the worktable, then you can achieve perfect grinding much easier than when moving a large workpiece.

The engine must be tightly placed on the frame. It should have a power of about 2.5-3.0 kW and a speed of about 1500 revolutions per minute. If you choose a speed of about 20 m/s for the sanding belt, then the diameter of the drums should be about 200 millimeters. Thus, with sufficient engine speeds, a gearbox for a grinding machine is not required.

One of the two drums will play the role of a leader, which should be rigidly fixed to the engine shaft, and the other tension drum should rotate freely around a fixed axis on bearings. The table on the side of the driven drum must have a certain bevel, which will ensure a smooth touch of the sanding belt on the desktop surface, this is especially true for a glued joint.

You can make a tension drum and a drum that leads the sanding belt from chipboard. To do this, you need to saw blanks from the plate overall dimensions 200 by 200 millimeters and from them assemble a package of 240 millimeters. Square tiles or their package should be folded on the axis and machined to a diameter of about 200 millimeters.

Remember that in the center the diameter of the drum should be 2-3 millimeters larger than at the edges. With such a surface geometry, the flexible sanding belt will be located in the middle of the drum. The optimal width of the tape is an indicator of 200 millimeters. From a roll of emery cloth, which has a width of 1 meter, it is easy to glue 5 similar tapes.

It is necessary to glue the cutting tool end-to-end, placing a thin dense material from below, for example, a tarpaulin. Glue is recommended to use the highest quality that you can get. On the rollers, without fail, stretch the rubber, the width of which reaches 30 millimeters. Rubber can be taken from the cameras of a moped or bicycle.

On a homemade belt sander, except for grinding wooden products, for which it is actually intended, it is very convenient to sharpen tools with cutting surfaces - chisels, knives, axes, secateurs. Another advantage of this grinder is the ability to work with parts that have a curved surface - for this you need to grind the workpiece reverse side working tape.

One of the main ways to process wood (after sawing, of course) is sanding. Manual way known for a long time wooden block wrapped in sandpaper, and with the help of such a simple device, the workpiece is given the desired shape.

The method is unproductive, and requires a fair amount of physical effort. Masters who work with wood regularly use small-scale mechanization.

Types of grinding machines

On sale are a variety of ready-made fixtures with which you can process wooden blanks of any size. To understand the mechanism of work, consider some of them:

Based on the name, the working surface is made in the form of a disk.

The design is quite simple - a circle with good rigidity is put on the axis of the electric motor. The outer surface has a Velcro coating on which sandpaper is attached. No gearboxes or drive mechanisms are required. The grinding force is small, the rotor axis copes well with the loads.

In the transverse plane, at the level of the center of the disk, a handrest is installed. It can be hinged, which allows you to process workpieces at a fixed angle.

A feature of disk machines is the adjustment of the processing speed without changing the number of revolutions of the axis. You simply move the workpiece along the radius of the circle. With a single angular velocity, the line speed at the periphery is higher.

A strip of sandpaper connected in a continuous band is stretched between two shafts.

And in the working area does not sag under the pressure of the workpiece. A persistent working plane is installed under the tape, made of a material with a low coefficient of friction. Pressing the material being processed to the plane, the operator gets an endless abrasive surface.

The quality, and the ease of processing, cannot be compared with hand tools. In the mass production of wooden products, such a sledge is an indispensable attribute of any workshop.

main feature- predictable result throughout the entire plane. You can level the ends of a sufficiently large length.

The working surface can be horizontal or vertical, as well as the direction of the tape.

Such a device can be attributed to grinding units with some stretch. The main application is the horizontal alignment of planes using the jointer method.

The principle of operation is as follows - sandpaper is fixed on one or two drums. The most common method is spiral winding. Below, under the drum, there is a flat table. The distance between the processing surface and the table is adjustable. By setting a fixed height, you can calibrate the same type of products, aligning the thickness of the workpieces.

Grinding machine two in one

To save space (and monetary resources), manufacturers often combine two types of fixtures in one design.

This not only reduces acquisition costs, but also improves user experience. When processing one part, you can enjoy the advantages of two grinding units at once: disc and belt. In this case, the engine is used alone, and the load on it does not increase much.

Everyone who was engaged in repair, reconstruction, manufacturing of parts and fixtures, faced with finishing work. Performing them manually is very difficult and time consuming, the process can take several hours or even days. Will do a great job Sander. There are devices for various purposes - from peeling to polishing. If it is not possible to buy a tool, it is made by hand.

Grinders - types and features of units

There are 3 types of grinders, which differ in specialization and functionality:

tape remove large layers from vast areas;
surface grinding is used for finishing;
eccentric work on the verge of polishing.

Many craftsmen who are professionally engaged in grinding have the entire set of these tools in their arsenal. The overwhelming majority of devices operate from 220 V. They are heavy and overheat. A pneumatic machine is lighter than an electric one, but a source of compressed air is required. Such units are produced by a few companies, the most famous being Bosch.

Tape machines - "tanks" among similar devices

Such a grinding unit with its working body in the form of an endless ring resembles a caterpillar machine, and is similar in shape. It is relatively powerful, its design is simple but reliable. From the engine, the skin belt is driven through a gearbox and a V-belt drive.

Works with all kinds of materials: wood, metal, polymers, minerals. Removes a few millimeters from the plane, performs rounding, edges. The quality is not the best - an orbital (eccentric) or surface grinder (vibration) machine is required for finishing.

Performance directly depends on the power of the motor. LSHM have engines of 0.5–1.2 kW. Another important indicator in technical specification of these units is the speed. A fast machine will do more, but it will not be possible to press it down due to the high torque. In addition, in this case, there is not enough power. For responsible manufacturers, the indicators are as balanced as possible, often the possibilities are regulated by electronics.

Fast machines are usually low power. If they are still given strength, it will be difficult to manage, the cost will increase significantly, with inept use it is easy to spoil the part. High-speed lightweight machines can easily process large areas in a short time. If the upcoming load on the grinder is unknown, professionals recommend for the home to choose a lower speed that can be pressed down (the usual range of devices is 150-550 m / min.). Even more convenient is the tape version with pre-set speed, for example, Dewalt DW433.

Surface grinders - the importance of the platform in the design

The devices occupy an intermediate place between tape and orbital tools in terms of processing cleanliness. They are popular due to their affordable cost, the availability of additional equipment, and the ability to finish fairly large areas, including corners. The motor is usually 150-300 watts, but there is enough power.

The main thing in such an ESHM is a plate moving in a forward-reverse direction with a high frequency. The most important characteristics:

1. The amplitude of the sole, which is mainly 1-3 mm. There are models where it reaches 5-6 mm. An increase in the indicator leads to faster processing, but less quality.
2. The frequency of the platform. A thicker layer is removed at high rates, but when they are lower, sanding is more accurate. Some devices, for example, Bosch GSS AEL-BOXX, have a speed of 20 thousand moves per minute.
3. Plate material and dimensions. According to the latter indicator, there are standard and mini (100 mm2). Budget models have a steel or plastic platform. Better from porous polymer with low vibration.

Emery is attached differently. Velcro is more convenient, but they are more expensive. Spring-loaded clips are more complex, but you can use paper cut by yourself.

Eccentric (orbital) machines - a guarantee of high-quality processing

They work both with a flat surface, and with a profile, volume, curvilinear, except for the angular one. The design is similar to the PCM, but the plate moves not only along the axis, but also orbitally with a small amplitude, which is set by the eccentric. Difficult movement and high speed provide high-quality surface treatment. Motors are usually 200–900 W: the more powerful, the more the sole is pulled.

Velocities (amplitude and orbital) are also different. The same rule applies here as for other types of aggregates: higher speed mode - more processing area per unit of time, but worse quality. An eccentric sander is rich in electronics, which is used to perform various functions: frequency support, brake, limiting starting currents.

The simplest grinders based on low-power electric motors

Somewhere in the far corners of the garage, a weak motor can be stored, which was forgotten as unnecessary. And it can be turned into a small section. device, which is useful in some cases. Alteration is simple, the main thing is the grinding wheel. In its role, they use the factory one, adapted to the device, or made independently from a suitable material.

Winchester from the computer in an unusual role

The old obsolete PC, which is covered with dust as unnecessary, now does not surprise anyone. But there is a node in it that will still serve in the household - this HDD. It is equipped with an electric drive, which is used to manufacture the simplest ESHM.

Hard drive grinder - installation sequence

Actions are simple:

1. Disassemble the device, remove the cover and remove everything that is on the left side of the disks.
2. Draw a circle of 9 cm on abrasive paper, cut it off. Where the leg of the compass stood, a hole is made according to the size of the spindle. Stick double-sided tape on the pancake of the hard drive, fix the sandpaper.
3. An aluminum can shield is installed to protect the operator's eyes. Connect to the computer's power supply.

The design will not surprise you with its power, but you can sharpen a knife with a small drill.

Polishing device from a car electric motor

Fan motors can be found in the garage. It can be used to do redecorating in the car and for other economic purposes. A neat little sander will eliminate the need to buy an expensive orbital machine to smooth out a small scratch or chip with your own hands, then paint.

There is a power source in the garage - this is car battery. Requires stranded copper wiring long enough to reach anywhere in the machine. The engine is powered by throwing alligator clips onto the battery terminals or through the cigarette lighter socket. A toggle switch is screwed to the motor with electrical tape to control the device.

A car electric motor is useful for a small ESHM

The working body is a circle. It is better to use ready-made with Velcro, which is sold for grinders. Only the mount needs to be done differently. There are many options, but in any case, it is necessary to machine the sleeve. Its inner diameter must correspond to the size of the motor shaft, and the interface must be the same - key or thread.

When it is planned to use the device not only in the garage, they make a portable option. A household battery is used as a power source. Both the motor and the switch are fixed on a piece of plywood, the wires are fixed with staples from a stapler. This machine can grind wood and metal surface to perform body work.

Reworking a household power tool

Almost every owner has a grinder. It can be used for rough finishing - to clean metal from rust, walls before plastering. For delicate work, for example, body work, it is not suitable - too high speed. One careless move - and a hole in the car. If you equip it with a voltage regulator, which is on professional models, then delicate grinding will become possible for household angle grinders.

Anyone who is at least a little versed in radio engineering will assemble the device with their own hands. You will need running parts that are easy to buy or solder from old products. Those who can read wiring diagrams do not need explanations.

Scheme of a homemade speed controller for a grinder

The order of work is as follows:

solder using printed circuit board or hanging installation;
thyristors are mounted on radiators;
test with a 40–60 W light bulb (it should smoothly change brightness when turning the tuning resistor);
after a successful test, the device is mounted under the tool casing.

The proposed scheme is simple, it is connected to the mains supply of the angle grinder.

Belt grinder from a grinder - device ideas

A small angle grinder is used as a drive, which costs a little, and almost everyone has it. The manufacturing work is simple: you need to make a frame for attaching the tool. They are different, so the bed in each case will be different. Other important components: the drive shaft and sandpaper wheels are all made from waste materials, no turning work is needed. It takes a little profile pipes, sheet metal, welding machine and grinder.

Circuit diagram and operation

The emery belt in the device moves on rollers, which are transmitted by rotation from an electric motor. In this case, the grinder acts as a drive, but you can just as well use a drill or any suitable motor. They are attached to the frame with reliable fasteners.

The principle of the tape device

To prevent the belt from sagging, a tensioning mechanism with a spring is used, which is pulled over one of the rollers. The stationary one differs from the manual unit by a table for fixing the workpieces. Safety is ensured by a transparent acrylic screen.

Industrial model

There are factory-made tape attachments for angle grinders on sale. They give the impression of being solid, heavy-duty designs, but users complain about poor fastening, an excessively long belt that requires powerful engine. So for purely practical reasons, and not just because of high cost many people prefer to make the prefix themselves.

Homemade car ideas

There are many original variants recycling of household power tools in order to expand the functionality. How to make a belt grinder from a grinder is shown in the drawing below.

The implementation of the second idea is more difficult. It is required first to make a bracket for the drive - the shape and dimensions may be different. Measure the tool, think over how to fix it. For manufacturing, steel plates are used, which are bent with the letter "P". Details are welded. The main task of this knot is to securely hold the grinder.

The bracket is hinged to the frame

The following photo shows a general view of the product. Here it is important to pay attention to 2 details that serve to adjust the tool. This is a spring between the base and the bracket, which is used to tension the working tape. There are also bolts in the mount. They are needed to change the angle of the angle grinder. This is necessary in order to achieve a position where the abrasive belt will be in the center of the drive wheel and will not fly off it.

Then they make driven rollers - there are two of them. Closed bearings are taken, which are put on a bolt of suitable diameter and length, fixed with a nut. From above they are closed with a piece of plastic pipe. A bicycle stand is used as a leader, which is installed to perform various tricks.

Lead Roller

The following photo shows a general view of the product. In front - a table made of a piece of sheet iron, welded to the base. Processing of parts is carried out with fixation on it.

stretch, but stay whole.

The sizes of the factory emery tape can be larger, but for a home-made device you should not take longer than 1230 mm. Otherwise, the dimensions of the product increase significantly, and these are unnecessary problems.

Self-manufacturing of a grinding machine is quite possible. The implementation of the options is not particularly difficult, the main thing is to choose the right drive.

If you need a grinder for occasional woodworking and do not want to spend money on professional equipment, you can assemble a power tool yourself using improvised materials, as in this project.

materials

To make a grinder with your own hands you will need:

suitable electric motor;
fasteners;
grinding disc;
pieces of plywood;
sandpaper;
drill;
saw;
roulette.

In this project, the basis of the tool was an old electric motor from air compressor. It is powerful enough to make the finished product work as well as special woodworking equipment.

Step 1. Be sure to attach the purchased grinding disc to the existing engine. This will help you decide on the parameters of the pedestal for the motor.

The base, after carefully making calculations, assemble from boards or pieces of plywood. Be sure to mount the motor on it.

Step 2. Cut out the base for the disk from plywood, carefully sand the edges of the cuts with sandpaper. Using the motor pulley, mark the holes in the center of the disk. Drill them with a drill, and bolt the pulley and the round plywood base together with bolts.

Step 3. In fact, the grinding tool is ready, you will need to fix the disc itself on the plywood base, and you can work in peace. Or you can, as in this project, assemble a box from the remnants of lumber so that the power tool looks nice on the outside, and also display the tool start button on its front part. Before assembling the box, be sure to make careful calculations.

Work with the received tool should be extremely careful and in compliance with safety rules. The speed of rotation of the disc is high and the likelihood of grinding off nails or injuring hands during processing small parts, high.

A do-it-yourself grinder is made from really very necessary “junk” that is in every workshop or pantry. The tool is used for final processing details, grinding, rounding corners.

There are several types of such a device. The most common is a grinder with a vibration principle of operation. One of its main elements is a flat sole fixed on the base. It transmits movement from the motor to the abrasive surface. The harder you press the device, the more powerful the vibration movements will be. Such a machine has a low speed, it is noisy, hands get tired quickly with it, but at the same time, such a tool is cheap and compact.

A subspecies of such a device is a device with a deltoid sole, which is brought forward.

Grinding machines types and purpose

Tape devices. Such a machine works on a different principle. A tape of abrasive material (sandpaper), glued into a ring, rotates on spindles. When working with it, you do not need to apply great efforts, since the rotation of the tape is quite fast. Such machines have speed control functions, a soft start system. For more precise work, tape machines have a support frame. When working with such a tool, a lot of dust arises, so they often have a dust collector or the ability to connect to a vacuum cleaner. Various attachments can be attached to the spindles.

eccentric device. This is the most versatile type among grinders. It can process almost any surface and materials. For curved planes, such a device is ideal. It has a round platform. The rotating abrasive is fastened with special clips or Velcro. The sole of the machine performs both rotational and vibrating movements at the same time.

Angle grinders. They are electromechanical and pneumatic. They are quite versatile, they can cut, grind, clean surfaces made of stone, metals. The device is very similar to the grinder, basically it is the grinder, but with special circles.

Polishing machines differ from angle polishers only with polishing nozzles.

Straight grinders perform fine work with high precision. The spindle is parallel to the frame, like the shaft of a pen. Such machines are small in weight and size, they can be manipulated with one hand. Their main purpose is the grinding of corners, the processing of edges and small planes, such as planks and lintels. They look like a thick pen, they are used to engrave, cut and polish small objects.

Multifunctional grinders. They can combine several types of devices in one device, for example, a vibrating and tape machine, using replaceable nozzles.

DIY grinder video

Tools and materials for assembling a grinder

wooden bars, metal elements for the base table;
sheets of plywood, chipboard;
old motor, computer hard drive, power supply;
bolts, screws, bearings, self-tapping screws;
screwdriver, screwdrivers, drill;
spring, steel, metal, textolite plate;
welding inverter, if such work will be carried out;
abrasive tape, circle, glue.

Making a grinder from a hard drive

Now it's not a problem to get a broken hard drive from the computer (but the circle should spin up) and an old computer power supply. If there is no house, then at any repair point they will be sold for a penny.

Such a device will be oversized, for small parts. It is done simply: the disk is disassembled, an abrasive is glued onto the rotating plane, connected to the power supply - the device is ready. It must be mounted on a workbench for stability, it can be equipped with a regulator, a servo tester for speed control and a switch.

Do-it-yourself angle grinder is made from a grinder, it is enough to make the necessary nozzle-circle from an abrasive. You can, of course, make it from scratch by selecting the necessary electric motor, placing it in a casing, attaching handles. But you need to remember about the safety of working with such a tool.

Belt grinder machine. Such devices consist of:

working body: abrasive, two drums, leading and driven. There may be more drums in the machine;
electric motor;
casing, machine base, frame, table.

The do-it-yourself machine is equipped with a speed change function, the tape can be placed both vertically and horizontally.

Stages of manufacturing a grinder-machine of a tape device

Preparation;
equip the base-frame for the machine, it is rigid and stable;
pick up the countertop, the larger it is, the larger parts can be processed;
fix racks with tension parts and rotating drums;
fixing the engine and drums, installing an abrasive belt.

To process large parts, they make an overall machine. To do this, take an electric motor, well suited from old, powerful enough household appliances like a washing machine.

The bed is made from a thick metal sheet.

Do not indicate the dimensions of the sheet, since in any case they come from individual preferences and the availability of materials, it can be, for example, 500x180x30 mm, more or less. A cutout for the motor is milled in the sheet, all this is attached to the frame, the necessary holes for the fasteners are drilled. All parts, and especially the engine, must be tightly fastened so that there is as little vibration as possible.

The motor can not be equipped with a gearbox if it is powerful enough. The do-it-yourself machine is created from two drums, one is firmly fixed on the shaft, the other is tensioned with it, you can adjust the degree of tension.

The frame is made up of thick wooden parts, but it is possible with metal ones. If there is a suitable metal and an inverter for welding, it can be welded. The plate for the support is made from thick plywood, I take several sheets, textolite is also suitable.

The second shaft is beveled, so the tape will smoothly touch the table. For drums, several sheets of chipboard are taken, they are glued and turned to the required diameter, in the center they are made several mm thicker, so the tape will hold well. Single row ball bearings are used for drum spindles. The abrasive belt makes its movement along the frame on which it is attached.