Belt sander: we study and do it ourselves. Budget belt sander DIY sander

Hand-held power tools at the moment have become widespread, which no master craftsman can do without them. However, sometimes this toolkit is not enough, and there is a need for serious equipment for your workshop. So, in my practice, the period came when a belt sander became necessary, which would allow processing the surfaces of large parts.

Industrial models of grinding machines are too expensive. Therefore, I had to come up with something myself. A conventional hand-held belt machine, in which a continuous sanding belt moves along the rectilinear surface of the sole with the abrasive side outward, seemed to me the ideal constructive prototype of a home-made machine. Naturally, my machine will turn out to be much larger, and it will be installed permanently.

It so happened that I needed to process a large number of parts about two meters long. This determined the dimensions of the table and the future machine itself. (photo 1).

The electric motor did not have to be chosen. I installed a 2.5-3.0 kW motor I have on the machine with a speed of 1500 revolutions per minute. If the belt speed is chosen to be about 20 m / s, then the drum diameter should be close to 200 mm. Thus, it turned out that at the speed of our engine, a gearbox is not required for the machine.

Of the two drums, one plays the role of the lead. It must sit rigidly on the motor shaft, and the other - tensioner - rotate freely on bearings around a fixed axis. To adjust the belt tension, it is enough to shift this axis along the working table in one direction or another. (photo 2)... I built the table from thick pine logs, but now I think it should have been made of sheet metal. "

It is quite obvious that the distance between the shafts and the length of the sanding belt depend on the length of the table. The size of the entire platform on which the machine parts are mounted (an electric motor with a driving drum, a working table, a driven drum with a tensioner) is also decisive. On the side of the driven drum, the table must have a bevel (photo 3)... providing a smooth touch of the tape (especially its glued joint) to the surface of the desktop.

Make a leading sanding belt (photo 4) and tension (photo 5) drums can be made of chipboard. To do this, it is enough to saw billets with dimensions of 200x200 mm from the slab and assemble a package of 240 mm from them. Square tiles - each separately or (if the lathe allows) together, folding the workpieces on the axis, - grind to a diameter of 200 mm. The latter option is preferable, since the drum can be made in one setup. It should be borne in mind that the diameter of the drum in the center should be 2-3 mm larger than at the edges. It is known that with this surface geometry, the flexible tape will be held in the middle of the drum. In my opinion, the optimal belt width is 200 mm. From one roll of emery cloth 1 m wide, 5 such tapes can be easily glued.

If at the very beginning I expected to process exclusively wooden blanks (photo 6-10), then in the process of operation, he opened and additionally quickly and efficiently sharpened special tools, for example, various profile full-assembly cutters.

It turned out that the longer the working table, the more opportunities for imagination when choosing a technological method for processing a product. Personally, I had to work with a belt of about 4.5 m, while the length of the processed parts reached 2 m. This does not mean that the length of the workpieces cannot be even greater. Under certain conditions, the length of the workpieces to be ground may not matter. If they are narrow, then any of them are the capabilities of the machine. Now I do not need to go to specialized workshops for sharpening cutting tools: planers, jointers, planers and others (photo 11-13)... The quality of sharpening axes (photo 14), knives, chisels and various chisels, I could not achieve before on any universal grinding equipment. And if you remove the wooden table and make it out of iron, then it will be easy, you can put it on an abrasive belt (photo 15). But when the length of the workpiece is equal to or less than the length of the table, it is much easier to achieve perfect grinding of the entire surface than when moving a large workpiece.

The belt is used in cases where it is necessary to perform finishing of parts, that is, as equipment for the implementation of finishing technological operations. Most often, such machines are used in the furniture industry, with their help they process parts made from wood of various species. But a belt sander can also be used for processing metal parts, for which a belt with an appropriate abrasive material is used.

Applications of the machine

The main tasks that the belt machine of the grinding group performs are: final leveling of the processed surface, bringing the surface roughness to the required level, bringing the processed surfaces to the level of smoothness before they are coated with varnish and other finishing materials. Also, a tape machine is used to eliminate minor defects in the processed surface: depressions, elevations and burrs, finishing treatment: removing slugs of primer and varnish, burrs, grinding internal surfaces, processing curves on the surface of a part.

A factory-made version, the drawings of which can be used to create a similar home-made device.

The band machine can be used to process parts made of various materials: wood, simple and non-ferrous metals. What is convenient, you can process parts with a band machine that have various shapes: quadrangular, round and flat. With the help of such equipment, it is possible to process round and tubular parts with a large diameter of their cross-section.

Design features of the machine

The working tool of any tape is a tape on the surface of which an abrasive powder is applied. It is made in the form of a ring and is placed between two rotating drums, one of which is the master and the second is the slave.

Rotation to the drive shaft of the band machine is transmitted from an electric motor, which is connected to it by means of a belt drive. The speed of the belt mechanism can be adjusted, thereby changing the modes of processing parts. The belt of a surface grinder can be positioned horizontally or vertically, as well as at a certain angle, which is allowed by some models of equipment in this category.

When choosing a model of a belt sander for processing a particular part, it is important to take into account the length of the surface that needs to be sanded. It is much more convenient to process parts on such machines, the length of the surface of which is less than the length of the abrasive belt and the working table. If these conditions are met, the processing quality will be much higher.

The belt sander can have various designs: with a movable and fixed working table, with a free belt. Wide-belt equipment belongs to a separate category, the peculiarity of which is that their working table, which is at the same time a feeding element, is made in the form of a caterpillar. In those models of equipment in the design of which a working table is provided, the abrasive belt is located in a horizontal plane, and in equipment with a free belt in which a working table is not provided, it can have a different spatial position.

An indispensable structural element of any belt sander, including a table-top one, is an exhaust device, which is necessary to remove dust generated in large quantities during processing. Whether professional or any homemade sander used in a home workshop or garage is powered by an electric motor.

Principle of operation

The main parameters of the belt sander are the feed rate and the force with which the belt is pressed against the workpiece. Parameters such as the degree of graininess of the abrasive belt should be selected depending on what material the workpiece is made of, as well as on the degree of roughness that the surface of the workpiece should have.

The characteristics of the material to be processed, in particular its hardness, primarily affect the grain size with which an abrasive belt should be selected. The processing modes, which are directly related to each other, are feed rate and belt clamping force. So, if you grind at high speed, but with a slight pressure of the abrasive belt, then some parts of the surface of the part may be untreated. If, on the contrary, you increase the clamping force and reduce the feed rate, you may encounter the fact that burn-through and blackening of the material may appear in certain areas of the treated surface.

Another variation of the machine is a view from the side of the working surface of the belt

The sanding results are also influenced by how well the abrasive belt is glued. To get a high quality finish and not to encounter malfunctions in the operation of the belt machine, you should not use abrasive belts that are not glued correctly or have torn edges. When putting the tape on the equipment shafts, position it so that the overlapping end of the seam does not lift up against the surface of the workpiece, but slides over it. Learn more about gluing tape in the video below.

Anyone, including a hand-held grinding machine, should provide for the possibility of adjusting the belt tension, which is ensured by moving the movable shaft, which is not a drive shaft. Belt tension is a very important parameter, when choosing which one should be guided by the “golden mean” rule. If the belt of the grinding machine is pulled too tight, it can lead to its breaking during operation, and too weak belt tension causes slippage and, as a result, its excessive heating. The main characteristic for determining the degree of belt tension is its deflection arrow, which is measured by lightly pressing on its surface in a taut state.

The manual belt machine of the grinding group can be operated by one operator, who moves the working table with the workpiece and rotates it so as to bring all sections of its surface under the abrasive belt.

How to make a belt sander

Many home craftsmen and professionals are wondering how to make a grinding machine with their own hands. The reason for this question is quite simple: the high cost of serial grinding equipment, which, with irregular use, not everyone can afford. In order to make such equipment, you will need several basic components: an electric motor, rollers and a reliable bed. Naturally, drawings of such a device or its photo will not be superfluous. Also, at the end of the article, you can watch videos on assembling a band machine on your own.

The motor for belt sander is easy to find and can be removed from a used washing machine. The bed will have to be made independently, for this you can use a sheet of metal with dimensions of 500x180x20 mm. One side of the bed should be cut very evenly, since it will be necessary to attach a platform to it, on which the electric motor will be mounted. The platform for the electric motor should also be made of a sheet of metal with dimensions of 180x160x10 mm. Such a platform must be fixed to the bed very securely with a few bolts.

Another version of the bed

The efficiency of a belt sander directly depends on the characteristics of the electric motor that is installed on it. If you are going to make a grinding machine with your own hands, then an electric motor with a power of 2.5-3 kW, which develops about 1500 rpm, is quite suitable for you. In order for the sanding belt to move at a speed of 20 m / s when using such a motor, the drums must have a diameter of the order of 200 mm. What is convenient, if you choose a motor with such characteristics, then you do not need to make a gearbox for your grinder.

The drive shaft is directly connected to the motor shaft, and the second, the driven shaft, must rotate freely on the axis, which is installed in the bearing assemblies. In order for the abrasive belt to touch the surface of the workpiece more smoothly, the section of the bed on which the driven shaft is installed should be made with a slight bevel.

It is possible to make shafts for a belt sander with minimal financial costs from a chipboard plate. Just cut square blanks 200x200 mm in size from such a plate, drill central holes in them and put them on the axis with a package with a total thickness of 240 mm. After that, you just have to grind the resulting package and make a round shaft with a diameter of about 200 mm out of it.

Drawings and detailed analysis of some parts of the machine made of wood.

Wood belt sander (click to enlarge)

Table Tilt Adjustment Mechanism Plate Block Belt Tensioner Machine Assembly

When the work with the wooden surface comes to an end, the stage of finishing sanding begins. To perform grinding without burrs, scratches, beautifully round off sharp corners of any part, you need to use a wood sander. This tool will help to perform professional grinding, even for a beginner who first took the device in his hands. If you wish, you can make a sander yourself, using only available tools.

The industry produces several types of machines that differ both structurally and in purpose. Here are the main ones:

Eccentric or orbital, in this case the sole of the instrument simultaneously rotates around its axis and in a certain orbit. It turns out that each time it passes a little in a different place, so scratches and burrs are rubbed down more and more with each pass.

Vibration model. Here the work sole performs reciprocating movements with a frequency of about 20,000 movements per minute. It is due to these movements that grinding occurs.
Angle grinder, which is popularly called "grinder". With this tool, rough processing of parts, large logs, etc. is carried out. For processing, abrasive wheels of the required grain size are used.
Belt sander that is usually used for working on large surfaces. Structurally, it consists of rollers driven by an electric motor, on which an emery tape is put on.

Making a belt sander with your own hands + (Video)

It is not at all difficult to make a belt sander yourself, you must complete the following steps:

select suitable materials and parts;
make a solid foundation for fixing the tool;
install a suitable countertop;
fix the vertical struts with a tensioner and a drum;
mount the motor and drums;
fasten the sanding tape.

To process fairly large parts and elements, it is necessary to make a large copy of a serial grinder. For example, if we take an electric motor with a power of 2 kW or more powerful with a rotor speed of 1500 rpm, then the gearbox can be omitted. The power of such an engine is quite enough to rotate a drum about 20 cm in diameter and process parts about 2 m.

You can also use an electric motor from an old washing machine. In this case, the frame is made of a thick sheet of iron, preparing a place for installing the motor and carefully fixing it with bolts to eliminate vibration. The design of such a machine is 2 drums, and one of them is fixed, and the second can be pulled and rotated on bearings around an axis. It is advisable to make the basis for the machine from metal or several sheets of thick plywood. The drums are made on a lathe from chipboard. The tape is cut from sandpaper sheets with a width of about 20 cm and fixed on the bed. The larger the table size, the larger the parts can be stacked and processed in the future. Drawings of finished products can be found online.

https://youtu.be/vDs1gBM_MW4

We make a grinder from a grinder

Many may say that the "grinder" is the same is an angle grinder, but there are some subtleties hidden here. It should be borne in mind that angle grinders have very high revs and often quite a decent weight. To polish the surface with a grinder, you must have considerable experience in this matter and use special polishing discs and wheels. The sander has a much lower engine speed and weight. To work with a factory grinder, no particular experience and dexterity is required.

It is possible to independently make a good grinder out of a grinder, which is not inferior in its parameters to a factory machine, only by finalizing its electrical circuit, by mounting the regulator at lower speeds and by using special grinding nozzles.

We make a grinder from a drill

To turn an ordinary household electric drill into a grinder, you need to equip it with a special attachment - a working drum or a special support plate, depending on the task at hand.

The backing or sanding pad is a plastic or rubber base with sandpaper glued on and a shank for clamping into a drill chuck. Trays with a flexible shaft are suitable for working with a loose drill, while with a rigid one it is better to use only for a well-mounted drill.

Grinding drums for household drills are structurally a conventional cylinder, a shank and sandpaper glued to the cylinder. When using drums, the working surface of the grinder is parallel to the axis of rotation.

Making an orbital sander

Currently, making an orbital machine with your own hands is possible only from a broken orbital machine. This is due to the complex device for rotating the working disk, which is quite problematic to repeat on your own. It should also be borne in mind that a machine made by a specialized company will not cost too much, and making it with your own hands will be very difficult and take a lot of time.

Making a grinder from a computer hard drive + (Video)

Any old hard drive can be converted into a miniature sander. To do this, follow these steps:

completely disassemble the hard drive and remove from the case everything that is located to the left of the magnetic disks;
cut out the working circle from sandpaper, make a hole for the spindle in the center of the circle;
stick several strips of double-sided tape on the rotating disk of the hard drive and fix sandpaper on it;
make a protective screen that protects the eyes from the possible departure of the manufactured emery disc;
connect the finished structure to the power supply from the computer and use.

Of course, this design does not have high power, but it is quite possible to sharpen a small knife or scissors.

Grinding machines from the manufacturer are expensive and therefore if they are used infrequently, then you involuntarily wonder whether to buy it or not.

And if, in addition, there is no free money available, then you have to make something with your own hands. So it happened with this homemade grinding machine.

The simplest hand sander was taken as a sample (read how to choose an eccentric sander). In such a grinder, the abrasive belt moves along the surface of the sole, with the rough side outward (abrasive).

That is, in the future belt sander I laid down the same principles in advance, changing only the dimensions in the plans - I need a large machine so that it can be processed by grinding parts at least 1.9-2 meters, and must be installed permanently.

The whole design of the grinding machine is based on an electric motor with a power of 2.8 kilowatts and a speed of 1500, I already had one, so I didn't have to buy anything.

There was no need to install a gearbox, because with an electric motor of such power, in order to achieve a normal belt speed (which will be quite enough for grinding) of 20 meters per second, the drum diameter should be only about 20 centimeters.

There are 2 drums in the design: one, which is rigidly fixed on the shaft, is the driving one. The second is a tension one, it rotates around an axis on bearings.

To tighten or loosen the sanding belt, it is enough to adjust this axis in any of the 2 sides.

The table of the machine is made of thick boards, if possible in the future I will redo it and make it out of metal sheets.

The length of the working part of the machine, as well as the belt itself for grinding, depends, first of all, on the length of the working surface of the table. The second shaft is equipped with a bevel as shown in photo # 3, this is necessary in order to ensure the smoothest possible touch of the tape to the edge of the table.

Both drums can be made from ordinary chipboard. To do this, cut square tiles 20 by 20 centimeters and assemble a workpiece of 24 cm from them and then grind them on a current machine to a diameter of 20 centimeters. When making a drum, take into account the fact that the tape will stick to it better if it is a couple of millimeters larger in diameter at its center.

About the sanding belt. Through trial and error in practice, I have established that the best sanding belt width is 20 centimeters - with this width, you can complete all the tasks facing the machine and, moreover, cut 5 such belts from a meter roll of sandpaper, without any residue.

In addition to grinding wooden parts, for which it was originally intended, on such a homemade machine it is very convenient and quick to sharpen any tools with cutting surfaces - knives, chisels, axes, knives, secateurs, etc. The sharpening quality is excellent.

In principle, if the design provides for the manufacture of a table not from wood, but from metal, then more complex, special tools can be sharpened, which no universal device can handle.

I emphasize once again - in this machine, a lot depends on the length of the table. It is she who gives you scope for opportunities, because when the part is less than the length of the working surface of the machine, it is much more convenient to process it and the processing will be of higher quality. For example, with a sanding belt length of four and a half meters, you can easily process wood pieces with a length of 200 cm.

Another plus of such a do-it-yourself grinding machine is that with some skill, you can also work with parts that have curved surfaces (as shown in photo 16) - for this, it is enough to remove the wooden table and, putting the workpiece on the bed, grind the part the back, underside of the working belt.

DIY belt sander: photo

Below are other entries on the topic "How to do it yourself - a householder!"

How To Make A Homemade Grinder Recently ...

Woodworking is a highly efficient machine for processing material planes. Using such units, you can quickly and efficiently process wood, getting perfectly flat surfaces.

Classification

The wood sander is used at the final stage of wood processing. In the course of work, special rough circles, tapes, powdery pastes are used.

Currently, based on the purpose, the following units are distinguished:

Circular grinding automatic devices.
Devices designed for processing the internal surfaces of parts and workpieces.
Surface grinding machines.
Specialized models that are used to implement highly targeted tasks.

Applications

The areas in which a wood sander can be used are extremely varied. The latest advances in the field of carpentry processing of parts make it possible to replace large turning units with more convenient mobile devices in operation.

Common solutions such as a drum and belt sander for wood can be successfully used for:

Rough rough grinding of workpiece surfaces.
Precise processing of wood surfaces.
Obtaining refined surfaces.
Cleaning bar and panel parts, their side and end edges.
Intermediate sanding of paints and varnishes.

Due to the wide range of operation, the wood grinding machine is one of the most demanded units among professional carpenters. Manufacturers are constantly improving popular models and offer the consumer a whole host of additional tools for performing complex, specific tasks.

How to assemble a wood sander with your own hands

We propose to consider the features of self-assembly of a drum device for processing the outer surface of wood. This will require several functional structural elements. Some of them can be found in the household.

Engine

The easiest way to assemble a wood sander is to remove the engine from your old washing machine. Fortunately, Soviet-made models are gathering dust idle in many closets. From here you can also take belts, pulleys and electrical parts.

However, any motor with a power of 200 to 300 W is suitable for assembling a grinding unit. It is desirable that its design be compact in size.

If you need to obtain maximum efficiency indicators, you will have to find an asynchronous motor capable of delivering 1500-3000 revolutions.

Drum

This structural element can be made using all sorts of leftover building materials. Sometimes, in order to assemble a drum sander for wood, it is enough to take a pipe covered with old linoleum, rubber rings glued together or cylindrical bars fixed on a metal axis. Let's take a look at the first of these options.

To make a drum, it is enough to use a piece of PVC pipe, a metal rod, a solid board, screws, glue and linoleum. Plugs are cut out of wood, corresponding to the section of the existing tube, in which holes are drilled for the rod. Such locking elements are inserted into the pipe and secured with screws.

A metal rod is passed through the plugs and sits on the epoxy adhesive. A layer of dense linoleum is glued on top of the PVC pipe. Alternatively, you can use rough rubber. Such a shell will act as the basis for securing the sandpaper. You can fix the latter on the finished drum using double-sided tape or staple staples.

Frame

For the manufacture of the case, where the homemade wood sander will be placed, ordinary plywood will do. You can make a structure of a rather unassuming structure. It is enough to install side panels, work table and additional reinforcement struts. If desired, a metal sheath can be made.

Mounting

The motor is securely mounted on a static-mounted base. The torsion shaft is threaded through a previously prepared hole in the wall of the housing. The grinding drum is installed in the upper part and rests on bearings in cages, which are fixed on the side walls of the structure.

Pulleys are attached to the axis of the drum and engine. The drive belt is tightened. Wiring and switches are connected. Clamping bolts are screwed in on the sides of the body, and adjusting bolts in the lower part of it.

To give the structure a complete and attractive look, you can paint the surfaces. Naturally, it is necessary to take on such work before assembling and installing the unit. To increase the safety during the operation of the device, the design can be supplemented with a protective casing located above the drum.

Finally

Thus, we tried to consider the main classes of grinding machines, their areas of application, and also gave an example of self-assembly of a drum-type unit. Ultimately, the decision to buy a factory-made device or assemble it from available materials depends on the budget, the goals set, the available funds, and the needs of each individual user.

Greetings to all those who work with metal and not only, I present to your attention a simple, convenient, powerful grinding machine. With this, you can easily and quickly form bevels on knives, sharpen axes and many other tools, perform grinding and so on. As a power unit, a 220V engine with a power of 2 kW is used, the speed of which is 2800 per minute.
The belt on the machine is installed with dimensions 1000x50, and the speed is 20 m / s.

This is very convenient to use, the belt changes quickly. It is also reliable, there is practically nothing to break, such a powerful engine is difficult to overload. The machine is also easily assembled from available materials. The most important thing is to find the right engine for your DIY. So. Let's consider in more detail how to assemble such a machine.

Materials and tools used by the author:

List of materials:
- motor 220V, 2 kW, 2800 rpm;
- square steel pipes;
- Sheet steel;
- wires;
- nuts and bolts;
- shock absorber (will work as a tensioner);
- finished wheels (or they can be carved out of wood yourself);
- dye.

Tool list:
- cutting machine or grinder;
- drilling machine;
- grinder;
- vice;
- welding machine;
- chisels, hammers, wrenches, etc.

Belt sander manufacturing process:

Step one. Base and stand
And as a base, we need thick sheet steel. The metal must be strong, since this is where we will mount the engine, as well as weld the strut. Choose a suitable piece of metal and mark it out. The author drills holes in the corners of the sheet, they are needed in order to screw the legs. You will need rubber legs, we fasten them with bolts and nuts, so our machine will not walk on the floor and will be securely fixed.

Next, we prepare blanks for the manufacture of the rack. Our stand is telescopic, that is, it is a pipe of larger and smaller diameters, they fit into each other. We cut off the necessary pieces of pipe on a cutting machine or grinder. Next, weld the wider pipe vertically to the base. The pipe must be welded evenly and as tightly as possible. We use corners to weld the pipe strictly vertically. That's all, the rack is ready, let's move on.

Step two. Adjustment unit
Making the adjusting unit is the longest in this homemade product. This node is needed in order to change the angle of the upper driven wheel. Thanks to this parameter, we center the belt on the wheels. This unit is made of steel plates, in more detail the assembly and operation of this unit is shown in the photo. There is nothing complicated in manufacturing, we cut blanks, drill holes, cut threads where required.

This adjuster is then assembled on a long steel plate that is welded horizontally to a thinner steel tube that slides out.

Step three. Assembly
The author showed us only the main points on the assembly of the machine, other details were behind the scenes. So, for example, you need to install some kind of spring that will "move" the telescope and thereby tighten the sanding belt. For the author, this is a shock absorber, something similar can be found in some washing machines. You can also adapt an old Soviet aluminum pump for this by installing a spring inside.

You will also need to install work planes on the frame, this is the table itself and the thrust platform. This is all made of sheet metal of a suitable thickness and shouldn't be a problem.

As for the wheels, you can carve them yourself out of wood, plywood is suitable as a material, several layers must be glued to obtain the desired thickness. We grind wheels on a lathe or on the engine that you found for the grinder. We fix the driving wheel on the motor shaft, and the driven wheel rotates on the bearing.

Everyone who was engaged in repair, reconstruction, manufacture of parts and fixtures faced finishing work. It is very difficult and time-consuming to carry out them manually; the process can take several hours, or even days. The grinder will perfectly cope with the task. There are devices for various purposes - from roughing to polishing. If it is not possible to buy a tool, it is made with your own hands.

Grinding machines - types and features of units

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

large layers are removed from large areas with tape;
surface grinders are used for finishing;
the eccentric ones work to the brink of polishing.

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

Tape machines - "tanks" among similar devices

Such a grinding unit with its working body in the form of an endless ring resembles a tracked vehicle, and is similar in shape. It is comparatively powerful, its construction is simple but reliable. The skin belt is driven from the engine through a gearbox and a V-belt transmission.

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

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

Fast machines are usually low-powered. 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. With high-speed, lightweight machines, it is easy to process large areas in a short time. If the impending load on the grinder is unknown, professionals recommend choosing a slower speed for the home, which can be pressed down (the usual range of devices is 150–550 m / min.). Even more convenient is the tape option with a preset speed mode, for example, Dewalt DW433.

Surface grinding units - the importance of the platform in the design

The devices occupy an intermediate place between tape and orbital instruments in terms of processing purity. They are popular because of their affordable cost, the presence of additional equipment, the ability to finish fairly large areas, including corners. The motor is usually 150-300 W, but the power is sufficient.

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

1. The amplitude of the sole stroke, 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. Frequency of the platform stroke. The thicker layer is removed at high rates, but when they are lower, grinding is more accurate. Some devices, for example, Bosch GSS AEL-BOXX, have a speed of 20 thousand strokes 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 made of porous polymer with low vibration.

Emery is attached in different ways. Velcro is more convenient, but they are more expensive. Spring loaded clamps are more complex, but you can use your own cut paper.

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

They work both with a flat surface and with a profile, volumetric, curved, except for angular ones. The design is similar to the PSHM, but the plate moves not only along the axis, but also orbital with a small amplitude, which is set by the eccentric. Sophisticated movement and high speed ensure high-quality surface finish. The 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: the higher the speed, the larger the processing area per unit of time, but the worse the quality. The eccentric sander is rich in electronics, which are used to perform various functions: frequency control, brake, inrush current limitation.

The simplest grinders based on low-power electric motors

Somewhere in the far corners of the garage, a weak motor may be stored, which was forgotten as unnecessary. And it can be turned into a small section. a device that will come in handy in some cases. The alteration is simple, the main thing is the grinding wheel. In its role, the factory is used, 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, is now no surprise. But there is a node in it that will still serve in the household - this is a hard disk. It is equipped with an electric drive, which is used for the manufacture of the simplest ESM.

Winchester sander - installation sequence

The actions are simple:

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

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

Polisher made from a car electric motor

There may be fan motors in the garage. It can be used to make cosmetic repairs in the car and for other household purposes. A small, neat sander will eliminate the need to buy an expensive orbital unit in order to smooth out a small scratch or chip with your own hands, then paint it.

There is a power source in the garage - it is a car battery. Stranded copper wiring is required long enough to reach anywhere on the machine. Power the engine by throwing crocodile 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 ESM

The working body is a circle. It is better to use the ready-made one with Velcro, which is sold for the grinder. Only the fastening needs to be done differently. There are many options, but in any case, you need to grind the sleeve. Its inner diameter must match the size of the motor shaft, and the mating must be the same - key or thread.

When it is planned to use the device not only in the garage, they make a portable version. 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. With such a device, you can grind wood and metal surfaces, and carry out body work.

Alteration of household power tools

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, bodywork, it is not suitable - too high revs. One careless movement - and a hole in the car. If equipped with a voltage regulator, which is on professional models, then a household angle grinder will become possible for delicate grinding.

Anyone who knows at least a little about radio engineering will assemble the device with his own hands. You will need running parts that are easy to buy or solder from old products. One who knows how to read electrical circuits does not need explanations.

Diagram of a homemade speed controller for a grinder

The order of work is as follows:

soldered using a printed circuit board or surface mount;
thyristors are installed on radiators;
testing with a 40-60 W light bulb (it should smoothly change brightness when the trimmer is turned);
after a successful test, the device is mounted under the tool cover.

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

Belt sander from a grinder - device ideas

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

Schematic 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 bed with reliable fasteners.

The principle of the device of the tape attachment

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

Industrial model

There are factory-made tape attachments for grinders on sale. They give the impression of solid, powerful designs, but users complain about poor fastening, excessively long belt that requires a powerful motor to drive. So for purely practical reasons, and not only because of the high cost, many people prefer to make the set-top box themselves.

Homemade car ideas

There are many ingenious options for recycling household power tools to expand their functionality. How to make a belt sander from a grinder is shown in the drawing below.

The second idea is more difficult to implement. It is required first to make a bracket for the drive - the shape and dimensions may be different. They 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 unit is to securely hold the grinder.

The bracket is attached to the frame with hinges

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 the spring between the base and the bracket, which is used to tighten the working band. There are also bolts in the mount. They are needed to change the angle of the grinder. This is necessary in order to achieve a position where the abrasive belt is centered on the drive wheel and does not fly off it.

Then they make driven rollers - there are two of them. They take closed bearings, which are put on a bolt of a suitable diameter and length, and fixed with a nut. Cover from above with a piece of plastic pipe. A bicycle footrest is used as a guide, which is installed to perform various tricks.

Lead roller

The following photo shows a general view of the product. In front is a table made of a piece of sheet iron, welded to the base. Parts are processed with fixation on it.

stretch out, but remain whole.

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

It is quite possible to make a grinding machine yourself. The implementation of the options is not particularly difficult, the main thing is to choose the right drive.

I decided to assemble this device to simplify the cleaning of the legs of radio components and other surfaces that need prepare for soldering.

Here is the actual detail that prompted me to come up with this idea:

You can get it from a Soviet cassette recorder.

We glue to it fine-grained emery:

Working part grinder ready, let's get down to creating a drive... We need any motor with a shaft diameter of 1.5 mm, it will ideally fit the attachment.

And a button of this type:

We bend the button mounts for subsequent fastening to the engine:

And we solder it to the electric motor in any place convenient for you:

One of the button pins is also soldered to the body.

We bend one leg of the motor and close it with solder to the body:

Now you need to deal with nutrition. I used a 7 volt AC adapter:

We begin to connect the adapter to the motor. Solder one contact of the adapter to the free leg of the switch, the other to the free leg of the electric motor:

That's all! The machine is ideal for cleaning seams and other small jobs. By the same principle, you can do small drill using a collet chuck. If a drill is already available, then you can leave the nozzle on the native shaft and simply clamp it into the chuck.

When carrying out construction and repair work, men often need to process wood, stone or metal. For quality work, it is advisable to purchase a belt sander. But what if the finances do not allow making 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 wide variety of manufacturing organizations. Many different parts and products are made from wood. 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 grinding equipment, as a rule, is used in the final stages of production, when parts are subjected to finishing machining. Such devices are conveniently used in the manufacture of furniture and various consumer wood products. Depending on the material used, belt grinders work with wood or metal.

The main purposes of using wood grinding machines are the final leveling of the surface, bringing their level of roughness to the required value, obtaining even and smooth surfaces of wood and wood products before veneering or after coating with varnish and other finishing materials, removing local irregularities in the form of recesses and elevations, deburring and removal of local build-ups of varnish and primer, deburring, internal grinding and grinding of curves.

Belt grinders for metal work with various materials and formats that are popular in metalworking: plain and alloy steel, non-ferrous metals in the form of rectangular, round and flat workpieces. Grinding machines allow you to grind round timber and large-diameter pipes efficiently and with minimal time expenditure.

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

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

Belt sander design

Belt grinders 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 in a ring and placed between rotating drums.

One drum is the master 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, with the help of which the torque from an electric motor is transmitted to it. Any belt sander is designed so that the speed of the driving drum, and therefore the speed 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 the bed, on which the workpieces are usually located. The workpieces can be held manually by the operator, or with the help of special devices that facilitate the work of consumers 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 from metal, then it will turn out to sharpen more complex products. The length of the working part of the belt sander and the belt itself for grinding primarily depends on the length of the products that will be grinded 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 be of higher quality. For example, with a sanding belt length of 4.5 meters, wood blanks that are 200 centimeters long can be processed with ease.

Belt grinders 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 at the same time a feeding device. For machines with tables, the tape is placed horizontally, for constructions with 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 process itself. 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 is 20 meters per second.

Abrasive belts for grinding machines

The cutting tool of belt sanders is a sanding belt, which consists of a cloth or paper base and abrasive grains that are attached to it with adhesives. Abrasive belts are made by two methods: mechanical and electrical. The first method consists in evenly pouring abrasive grains onto the base, which is covered with glue, and the second method takes place in an electric field, which orientates the grains upward with the sharpest edges to improve the cutting properties of the grinder.

Abrasive grains are poured onto the base in a bundle tightly or sparsely. An abrasive belt with a sparse backfill is considered the most effective, when the grains occupy less than 70% of the area, because wood dust generated during the grinding process is not able to clog between the grains. Natural minerals or artificial materials with high hardness can be used as abrasives, such as green and black silicon carbide, white and normal mono-corundum, and normal fused alumina.

For the purpose of gluing the grains, synthetic resins and skin glue are used. As a basis, they use a fabric such as coarse calico and twill, or special grade 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.

For woodworking enterprises, the sanding paper comes 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 belts 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 when gluing end-to-end at an angle of 45 degrees and then glued onto a linen lining with a width of 80 to 200 millimeters. At one end of the tape, when gluing with an overlap, the abrasive grains are removed with hot water for 80 to 100 millimeters, then the other end of the tape is applied to the exposed base greased with glue. Squeeze the joined ends and dry them using a special tool or a size press.

Sheet skins are used for combined belt grinders. For grinding discs, it is customary to cut the skin in the form of a circle according to a template, the diameter of which is 60 - 80 millimeters larger than the diameter of the disc. Using a rectangular template, the blanks are cut out for the bobbin. After cutting, they have smooth edges without tears. The presence of loose 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 made of plywood or aluminum sheet. The skin is cut in such a way that the edges are smooth, and the difference in the length of the side edges is no more than 1 millimeter. One of the beveled edges is cleaned by removing the abrasive at a width of 20 millimeters. The peeled edge and longitudinal edges are pasted over with a strip of tracing paper, which has a width of 40 millimeters, which protrudes from the edge of the skin by about 10 millimeters.

Lubricate the beveled edge with tracing paper with glue and stand in air, depending on the viscosity and type of glue. Then the beveled edges are connected and a strip of skin is applied to the joint, the joint is squeezed and held in the press. It is customary to hang finished endless belts on special brackets and keep them for at least 24 hours in a dry room before being installed on a grinding machine.

The operating principle of a belt sander

The belt sander consists of a table top with a work 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 25 millimeters thick. The working table on rollers is moved manually or in the transverse direction by means of a mechanical drive along round guides that are attached to the calipers.

Above the table there is a working belt, put on the non-drive and drive pulleys. The sanding belt is tensioned and adjusted by means of a screw device with a pneumatic cylinder. Double 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 carried out with the transverse movement of the working table and the longitudinal movement of a short iron, which presses the belt to the material being processed. The sanding belts are driven by an electric motor through a belt drive. Waste generated during grinding is captured by a dust collector, which is connected to the exhaust 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 grain size of the sandpaper, the feed rate and the pressure of the belt to the product. It is customary to choose the grain size of the skin, depending on the hardness of the materials being processed and the required surface roughness. The clamping force and the feed rate are interdependent quantities. With a small effort and a high feed rate of the sandpaper, some parts of the surface are not able to be sanded, with high pressure and low feed, burn-through and blackening of the material are possible.

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

The belt tension can be adjusted by moving the belt sander idler or non-drive pulley. It is not advisable to over-stretch the tape as this will cause it to break. But the sanding belt slips along the pulleys at low tension and heats up very quickly. The tensile force is set, depending on the strength of the base of the cutting tool and is determined by the arrow of its deflection with slight pressure on it.

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

Manual belt sander can be serviced by one worker. Moving the product relative to the cutting tool in the longitudinal direction, and turning the part around the axis, the operator in contact with the tape sequentially enters all the areas that form the surface to be machined. Slowing down or careless movement may result in sanding.

It is customary to grind individual parts of the part in several passes. Achieve high-quality alignment is possible with the correct regulation of the pressure that is applied to the iron handle, and the speed of movement of the table and iron. The pressure when approaching the edges must be reduced to prevent them from grinding. To increase the quality and productivity of grinding, small blocks 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 guides the product under the clamping elements of the machine. When gripping the conveyor, parts must not be moved laterally.

It is not allowed to feed into the machine workpieces with unequal thickness and parts with rough surface defects. The feed rate and pressure of the clamping beam are usually not controlled during processing. The second operator is engaged in the reception of finished parts and makes sure that there is no unacceptable rounding of the edges and grinding.

Belt sander manufacturing

The price of belt grinders from an industrial manufacturer is quite high, therefore, with their infrequent use, the 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 bed, rollers and the engine.

The motor can be removed from the old washing machine. Cut the bed out of thick iron measuring 500 by 180 by 20 millimeters. Cut one side evenly on a metal milling machine, it is required to mount the platform with the motor. The dimensions of the working platform are approximately 180 x 160 x 10 millimeters. Mark and drill three holes at the end of the flat-cut bed. It is necessary to tighten the platform to the bed with three bolts.

Remember that the longer the working table is, the more options you will have when choosing a technology for grinding and processing a product. If the length of the workpiece is less than or equal to the length of the work table, then you can achieve perfect grinding much easier than moving a large workpiece.

The motor must fit snugly on the bed. It should have a power of about 2.5-3.0 kW and a rpm of about 1500. If you choose a speed of the sanding belt of about 20 m / s, then the diameter of the drums should be about 200 millimeters. Thus, with sufficient engine speed, a gearbox is not required for the grinding machine.

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

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

Remember that the diameter of the drum should be 2-3 millimeters larger in the center than at the edges. With this surface geometry, the flexible sanding belt will be positioned in the middle of the drum. The optimal tape width is 200 mm. From a roll of emery cloth, which is 1 meter wide, you can easily glue 5 such tapes.

It is necessary to glue the cutting tool end-to-end, placing a thin dense material, for example, a tarp, from below. It is recommended that you use the highest quality glue you can get hold of. Be sure to pull rubber on the rollers, the width of which reaches 30 millimeters. Rubber can be taken from the cameras of a moped or bicycle.

On a homemade belt sander, in addition to 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 with the back of the working belt.