Do-it-yourself grinding disc machines. Design

Grinder (English) literally - a crusher. Meat grinder is a meat grinder, rock (stone) grinder is a stone crusher; stick (wood) grinder - garden crusher of branches and rods into chips. But there is also a completely unambiguous meaning of the word grinder: in mechanical engineering and metalworking, this grinding machine. A useful household item. For example, it is impossible to guide a dull meat grinder knife on a whetstone by hand. On a manual knife sharpener - somehow possible, with a solid working skill. And on the grinder - no problem. The same - if you need to grind the part complex shape without violating her profile. Or just sharpen scissors or professional knife. different kind cutters for wood and metal are best edited on a grinder too. It is quite possible to design and assemble a grinder with your own hands without having complex equipment and skills to work on it. In terms of money, this will mean savings from 50-90 thousand rubles. up to 3-6 thousand USD.

To make a grinder yourself, you will need to order a maximum of 4-5 turned parts, and it is often possible to do without turning from outside at all. For example, how to make the simplest grinder literally from trash, see the video below:

Video: do-it-yourself tape grinder from trash

Or another option, how to make the grinder stronger and more resilient from scrap metal:

Video: scrap metal grinder

Disk or tape? And drive

Almost more varieties of grinding machines are used in industry than lathes. Emery known to all craftsmen - a motor with a pair grinding wheels(or one circle) is also a grinder. For yourself at home, it makes sense to make either a disc end (plate) or a belt grinder. In the first, the abrasive is applied to a rotating HDD; in the second - on an elastic tape running around a system of pulleys and rollers. Disc is more suitable for grinding simple wooden parts and rough or medium cleanliness - metal. On a belt grinder, it is also possible to produce precise and clean finishing of profiled parts of complex shape, incl. large, see below.

A disc grinder is very simply obtained from the same emery or a motor of suitable power, see below. It is necessary to order an adapter from the motor shaft for the shank of a cup-shaped grinding wheel on a metal base. Or under a chuck, then on the same motor it will be possible to build a mini lathe, see fig.:

A worn-out “plate” is suitable: a disc made of thin (4-6 mm) fibrous plastic is glued onto the edge of its side, and an abrasive is placed on it. How to make an end grinder, see next. video clip.

Video: homemade end grinder

The difference between a disc grinder and a belt grinder is not only in the possibilities of use. If you take ordinary home crafts, then a drive power of 250-300 W on the shaft is enough for a disk grinder. For small wooden parts - and 150-170 watts. This is an old motor washing machine, straight (ordinary) drill or screwdriver. But for belt grinder you will need an engine from 450-500 W: three-phase with batteries of starting and operating capacitors. If it is supposed to process a large size, then the motor power is from 1-1.2 kW. Moreover, capacitor banks for both will cost a little less than the engine itself.

Note: a 100-200 W drive uses a mini belt grinder (see below) for fine dressing of knives, grinding / polishing jewelry, etc.

A drill or screwdriver as a grinder drive is also convenient in that it allows you to quickly change the speed of the abrasive (see below) with a standard speed controller. It is only necessary, firstly, to make a holder for the drill, rigidly fixing the tool. Secondly, an elastic adapter from the drill to the disc shank, because it is difficult to achieve their precise centering without special equipment, and the runout will negate the accuracy of processing and can damage the tool-drive.

Drill holder drawings for using it as a home drive metal cutting machine given on the left in the figure:

Since shock and irregular alternating loads on the drive in the grinder are an order of magnitude lower than, say, in lathe, the drill holder for it can be made from solid wood, plywood, chipboard, MDF, on the right in fig. The diameter of the mounting (large) hole is along the neck of the drill. The drill is highly desirable to use without percussion mechanism and with a steel shell on the neck (for the installation of the front handle).

Coupling

For the adapter, you will need a piece of steel bar (not necessarily turned) of the same diameter as the shank of the grinder drive shaft, and a piece of reinforced PVC hose (garden irrigation) with a gap so that it is tightly pulled over the bar and shank. The length of the “free” hose (between the ends of the rod and the shank in it) is 3-5 cm. The length of the protruding part of the rod should be sufficient for a reliable clamp in the drill chuck. After assembling the coupling in place, the hose on the shank and rod is tightly tightened with clamps; can be wire. Such a coupling completely parries the misalignment of the drive and the driven shaft up to 1-1.5 mm.

Ribbon is still better.

A belt grinder allows you to do everything that a disc grinder does, and more. Therefore, further we will focus on how to make a belt sander with our own hands. Amateurs, focusing on industrial designs, sometimes make grinders very intricate, see fig.:

And this is justified: the design and kinematics of the belt grinder are very flexible, which makes it possible to successfully use improvised materials and old scrap metal. You just need to follow 3 principles:

Do not do as in the second photo from the left: the tape with the abrasive side should only touch the workpiece. Otherwise, the abrasive will eat both the bypass rollers and itself. The accuracy and cleanliness of processing during one working operation will be unpredictable;
The design of the machine must ensure uniform belt tension, regardless of the nature of the operation being performed;
The speed of the belt movement must correspond to the nature of the operation being performed.

Kinematics and design

As mentioned above, there are many designs of grinders. Thinking about what and how to build a grinder for yourself, it is better to focus on industrial designs designed for fully mechanized precision and clean grinding of large-sized profiled parts: since the propeller blade of an aircraft or wind turbine “skins” as it should, then it will cope with any other work.

Kinematic schemes of grinders for the specified purpose are given in Fig.:

Main kinematic diagrams belt grinders (grinders)

Pos. A - the most complex and perfect, with three rocker arms. If the length of the tensioning roller rocker is approx. 2 times less than the working one, then by adjusting the tension of the springs, it is possible to achieve a uniform tension of the tape when the working rocker moves 20-30 degrees up and down. By tilting the bypass rocker, firstly, the machine is reconfigured for tapes of different lengths. Secondly, in the same way, you can quickly change the belt tension for different operations. The working branch of the tape can be any, except for the one running from the drive pulley to the tension roller, i.e. a grinder with 3 rocker arms is both horizontal and vertical at the same time.

A scheme with a coaxially swinging rocker (pos. 2) is simpler, cheaper and not inferior in processing accuracy to the previous one, if the length of the rocker between the axes is at least 3 diameters of the workpiece. In order to knock down the profile by grinding, the course of the rocker arm is limited by stops within 10 degrees up and down. The clamping of the tape to the part is most often gravitational, under the weight of the rocker with a bypass pulley. It is possible to quickly change the tension of the tape within certain limits by pulling the rocker up with a weak adjustable spring, which partly compensates for its severity. The grinder of this scheme can work as a grinder for small parts from a sliding table. In this case, the rocker arm is rigidly fixed horizontally, and the running surface of the tape will be a bypass pulley. According to the scheme with a coaxial rocker arm, for example, a fairly popular BTS50 grinder was made. The disadvantages of the scheme are, firstly, the technologically complex rocker arm hinge coaxial with the drive shaft. Secondly, the need for an elastic band: if you make the bypass pulley sliding spring-loaded, the machining accuracy drops. This disadvantage when processing small parts is completely eliminated by an additional tension roller, see below.

A scheme with one misaligned rocker arm in industry is used quite rarely, because. in principle, it does not allow to achieve a uniform tension of the tape. However, it gives an accuracy that is quite sufficient at home and allows you to build a very good simple grinder.

What's good for what

Now let's see what is possible to "squeeze" out of this or that scheme from the point of view of an amateur master. And then we’ll try to figure out how to make a belt for the grinder ourselves and do without custom-made turned parts.

3 rockers

Competent amateurs build their grinders exactly according to the scheme with 3 rocker arms, on the left in fig. below. Far from all propeller blades are ground, but in this case another advantage of this scheme operates: if the grinder is used as a vertical one, then the working branch of the tape is elastic. This allows a skilled craftsman, for example, to guide cutting edges and blades with literally micron precision.

In industrial grinders for home use the 3-rocker scheme is also widely used (in the center) for the same reasons. Repetition of them independently in most cases is quite possible. For example, drawings of the popular KMG grinder abroad can be downloaded.

The dimensions, however, are inch - an American typewriter. For the drive, in any case, it is possible to use an angle grinder drill (on the right in the figure, it is quite suitable in terms of power) with homemade pulley and rollers, see below.

Note: if you are making a stationary drive, try to get a 2-3 speed asynchronous motor from a worthless washer with a horizontal tank. Its advantage is low turnover. This makes it possible to make the drive pulley of large diameter and thereby eliminate belt slippage. A slippage of the tape in the work is almost certainly a damaged part. Most washing machines with 2-3 speed 220 V asynchronous motors are Spanish. Shaft power - 600-1000 watts. If you come across one, do not forget about the standard phase-shifting capacitor bank.

Coaxial rocker

In its pure form, grinders with a coaxial rocker are not made by amateurs. The coaxial hinge is a complicated thing, you can’t make an elastic band yourself, and a purchased one is expensive. Grinders with a coaxial rocker at home are most often used in the variant for fine precision work from the table, i.e. with a rigidly fixed horizontal beam. But then the need for a yoke as such disappears.

An example is a mini grinder, the drawings of which are given in Fig.:

Its features are, firstly, an overhead bed for the tape (pos. 7), which greatly expands the possibilities of use. For example, a planer iron is straightened on this grinder with an angle stop literally by itself. AT this case the grinder works, so to speak, like a self-propelled whetstone (emery bar). After removing the bed, we get a grinder with an elastic band for precise grinding / polishing of rounded small parts. Secondly, the tension shaft (pos. 12). Clamping it with a groove with nuts, we get a relatively fixed tension of the tape for working with the bed. And having released the nuts, we put the grinder into the mode of gravitational tension of the tape for fine work. The drive is not necessarily through a pulley (pos. 11). Can be screwed directly behind the drive shaft shank (pos. 16) from the drill through the adapter, see above.

A specialized tool grinder (for example, for aiming and dressing turning tools) generally loses any semblance of the original scheme. A high-speed motor is taken for it (a power of 200-300 W is enough). The drive pulley, respectively, of small diameter. The bypass pulley, on the contrary, is made larger and heavier, for inertia. All this together allows you to reduce the runout of the tape. The tension roller for the same purpose, plus for greater uniformity of the tape tension, is taken away and spring-loaded with a long, not very strong spring. How to make a cutter grinder, see the video below.

Video: cutter grinder

One rocker

In amateur practice, grinders with misaligned rocker are good because they do not need precise details at all. For example, hinges can be made from card loops. At the same time, the accuracy of processing remains sufficient for ordinary amateur requests.

The original scheme in this case is also modified: the rocker is rotated 90 degrees, carried up and spring-loaded, on the left in Fig. It turns out a simple vertical grinder. And, importantly, it works without problems with a home-made inextensible tape. Both tension spring (in the center) and compression spring can provide belt tension. Its strength is not important, as long as the tape does not bend excessively during operation. No adjustments are required during use.

Consumables and parts

The only one consumable for a belt grinder - tape (not counting grease for bearings and joints. The tape can be ordered in the desired length (see at the end), but you can also make it yourself from emery cloth on a textile basis. It is highly desirable - flexible, unimpregnated. In general, the procedure for making a tape for a do-it-yourself grinder is this:

We cut off the workpiece - a strip of the desired length and width.
We prepare a mandrel (not necessarily round) with a length along the generatrix slightly less than the length of the tape.
We circle the mandrel with the workpiece inside out.
We bring the ends of the workpiece exactly end-to-end and securely fasten.
We put a piece of glue stick for a hot glue gun on the joint.
Gray building hair dryer until the glue melts.
We impose a patch of thin fabric on the joint.
We press something hard through the Teflon film until the glue hardens.

There are three significant points here. The first is to use a rough PET film with a thickness of 25-50 microns (sold) instead of fabric on the patch. It is very durable, but try running your finger over a PET bottle. Not very slippery? A rough PET film under tension cannot be stretched over polished metal. And instead of a patch, it is better to seal the wrong side of the tape with a continuous strip of PET film with an overlap of 2-3 cm. The beating of the tape will be no more than 0.05-0.1 mm. This is less than from the thinnest calico and even less than the error in the thickness of the skin-blank.

The second - fill the finished tape into the machine and grind something obscene with it without strong pressure. The hem on the seam will come together, and the tape will become no worse than the branded one.

But most importantly - in terms of elasticity best glue for gluing the grinder tape is not expensive and difficult to use thermal or mounting, but ordinary PVA. If the tape is pasted over with a lining along the entire length of the inside, then its strength for PVA is more than enough. How to glue a tape for a PVA grinder, see the video

Video: gluing the grinder tape with PVA glue

Pulley

Generating ( side surface section) of the grinder drive pulley must be straight. If you use a pulley-barrel, then the tape will bend like a trough along its entire length. The rollers do not allow it to slip, see below, but the pulley generatrix must be straight.

A pulley for a grinder that is not designed for particularly precise work, firstly, does not have to be turned. In the scheme with 3 rocker arms, the beating of the tape from its misalignment will go out on the rollers before it reaches the working branch. In a simple vertical grinder, the belt runout will be sufficiently damped by the tension spring. Therefore, it is quite possible to make a pulley for a grinder without a machine, see video:

Video: drive wheel on a grinder without a lathe

The second is that the pulley, rollers and, in general, all the details of a home grinder can be made from plywood. In production, this is certainly not an option, even if the plywood grinder is offered for free with an additional payment: the grinder needs a salary, and the wooden grinder in the workshop will completely wear out before it pays for itself. But you won’t drive the grinder at home day after day in 3 shifts. And no tape slips along the plywood pulley. Incl. homemade. So you can safely make a grinder pulley out of plywood:

Video: plywood grinder pulley

It is much more important to correctly calculate the diameter of the pulley according to the speed of the motor and the required speed of the belt. Too slow running belt will tear the processed material; too fast - it will be erased by itself, without really processing anything. In which case, what tape speed is needed is a special conversation, and a very difficult one. In general, the finer the abrasive and the harder the material to be processed, the faster the belt should move. How the speed of the belt depends on the diameter of the pulley and the speed of the motor, see the figure:

Fortunately, for most abrasive-material pairs allowable limits belt speeds are quite wide, so the grinder pulley can be selected easier:

Video: which wheel is needed for a belt grinder

Rollers

The rollers of the grinder, oddly enough at first glance, are its most important details. It is the rollers that keep the tape from slipping and ensure its uniform tension across the width. Moreover, there can be only one video in kinematics, see, for example, the video above about the cutter grinder. Only barrel rollers will cope with this task, see below. But the “trough” of the tape after any roller should straighten out before it reaches the working area.

Rollers with flanges (sides, edges) will not hold the tape. The point here is not only and not so much with the misalignment of the axes of the rollers: the grinder tape, in contrast to drive belt, must withstand, without slipping, the loads from the workpieces. If you make rollers with flanges, then, just touching something to the tape, it will crawl onto the flange. In the grinder, you need to use Type 3 barrel rollers (highlighted in red on the left in the figure).

The dimensions of Type 3 rollers are also given there. It is advisable to take the diameter of the rollers no more than 0.5 of the width of the tape (so that the “trough” does not go far), but not less than 20 mm of steel turned and not less than 35-40 mm of plywood. The tension roller (the probability of the tape slipping from it is greatest), if the working branch of the tape does not leave it, can be 0.7-1.2 in diameter of its width. Plywood rollers are made in the form of a thick shell into which the bearing is pressed; then the roller is mounted on the axle (in the center in the figure) and finished clean, see e.g. track. video:

Video: barrel roller for grinder

Not every turner can machine a profile barrel roller exactly according to GOST. Meanwhile, there is a way to make rollers for the grinder without significant difficulties. The same garden reinforced PVC hose will help out, on the right in fig. previously. On the roller blank with a straight generatrix, its segment is pulled tightly and cut off with a margin along the edges to the thickness of the hose wall. It turns out a roller with a complex generatrix profile, which holds the tape even better and gives it a smaller “trough”. Don't believe? Try to get into the graveyard of planes or missiles and dig into them. You will find rollers with exactly the same generatrix profile. It's just that the mass production of rollers of a complex profile is much more expensive than Type 3 barrels.

And another option

All critical parts of the grinder - one-piece belt, non-slip coated pulleys, rollers - can be purchased separately. They will cost not so cheap, but still not in thousands of foreign and not in dozens of native "leather jackets". The remaining parts of the grinder, either flat or from professional pipes, are made using a conventional bench drill or drill. Here is where you can order grinder parts:

//www.cora.ru/products.asp?id=4091 - tape. Do lengths and widths at the request of the customer. Advise on abrasives and processing modes. The prices are acceptable. Delivery time - questions to Ruspost.
//www.equipment.rilkom.ru/01kmpt.htm - spare parts (accessories) for grinding machines. There is everything, the prices are divine. Delivery - see prev.
//www.ridgid.spb.ru/goodscat/good/listAll/104434/ - the same, but foreign-made. Prices are higher, delivery is the same.
//www.pk-m.ru/kolesa_i_roliki/privodnye_kolesa/ - drive wheels. You can find suitable for the grinder.
//dyplex.by.ru/bader.html, //www.syndic.ru/index.php?option=com_content&task=view&id=36&Itemid=36 – spare parts for grinders. Ribbons are not made to order - choose from the catalog. Rollers without axles; axles are sold separately. The quality is impeccable, but everything is very expensive. Sending - within 2 weeks to the border. Then - their customs, our customs, Ruspost. Total ok. 2 months It may not reach if some local bureaucrat considers the goods to be sanctions. In this case, there are no problems with the return of the payment due to the complete absence of real opportunities for an ordinary citizen to receive one.

5,00

The working surface of the wood after cutting needs special treatment. Eliminate roughness and other imperfections for further application paintwork sanding will help.

A do-it-yourself wood sander is able to perform the final technological operations related to sizing and leveling surfaces. At the same time, the cost of acquiring such equipment will be minimized. Unlike factory models, they are small in size, so they are easy to install in the workshop, in the garage or in the barn. To work with them do not need special qualifications. It is enough to know the functional features of the device and follow the safety precautions. Grinding machines are used in everyday life, in construction and in furniture production.

Design - the initial stage

Different models of grinding devices allow you to process all kinds of wooden materials.

Before you start making a homemade wood grinder, it is important to decide for what purposes it will be needed.

The technical parameters of the tool will depend on this:

The performance of the device is affected by its power. For home use 400 watts will suffice. High efficiency is provided by machines with a power of up to 1 kW.
The quality of grinding is affected by the speed of rotation of the working tool. The maximum figure is 3 thousand revolutions per minute.
Depending on the type of surface to be treated, the working area is calculated. The width of the drums of the machine depends on it.
The size of the machine is an important indicator of where the equipment will be used: in workshops or in a small home workshop.

A simple homemade grinder

Types of equipment

Woodworking machines have the same principle of operation - the surface is ground with an abrasive material, for example, sandpaper tape or circles with a rough surface.

Grinding machines differ from each other in structure and scope of use. The purpose of the device depends on which drawings you need to use in your work.

Belt machine

The simplest of all models for domestic use. It allows you to make adjustments in different planes, clean and give desired shape products.

The basis of its mechanism is an abrasive belt stretched between the shafts, which is located in a horizontal and vertical position or at a certain angle. Beneath it is a low-friction work surface against which the tool rests.

During operation of the device, the speed of the mechanism can be adjusted. There are several models of belt sanders. They can be with a stable and movable work table, and with a free belt.

An essential element of their design is exhaust device to remove dust. To make a homemade product, you will need an electric motor that can be removed from an old washing machine, rollers and a strong frame made of metal sheet.

Work items are made of chipboard. The drive shaft is directly connected by an electric motor, while the other is free to rotate on an axle mounted on bearings.

The abrasive belt from the emery cloth is located strictly in the middle of the shaft. It should smoothly touch the surface and not slip off.

To assemble the structure, you may need the following consumables:

boards and bars made of wood;
metal pipes;
bearings;
electric motor;
pulley;
rubber belt;
fasteners;
abrasive material;
working tool for installation;
welding machine, if the frame body is made of metal.

drum device

Necessary for horizontal alignment and surface calibration. With it, you can process slats and MDF and chipboard materials. The design of the device consists of two rollers with an abrasive belt stretched in a spiral.

Under them is a smooth tabletop on which the workpiece is located. The distance between the shafts and the working surface is adjustable.

Work on the manufacture of a drum machine is carried out in stages. First, a body is made of sheet steel or plexiglass, then the engine is mounted. An abrasive belt or a cone with cutting edges is attached to the drum.

A desktop is installed at the top of the diagram. It must be adjusted in relation to the vertical cylinder. The on and off buttons are used as controls.

disk device

Another simple homemade grinder is a disc grinder. It is necessary for turning large wooden products. As a working tool, an abrasive wheel is used, which is mounted on the axis of the electric motor.

A special stand is installed in the center of the disk on a hinged mount, fixing the part at a certain angle. To improve the equipment, experts advise using wooden discs with different types sandpaper.

Combined variant

Combines circular grinding and surface grinding equipment.

You can make the device in this way. A shaft with a disc with a diameter of up to 230 mm is attached to the increased frame of the belt grinder.

It uses a belt drive. The design is complemented by a support table. The combined technology will save space and provide convenience in work.

Proper operation of the equipment is the key to success

The process of installing a wood grinder with your own hands must meet all the requirements of safety regulations. Every foreman should remember this in order to prevent injuries in the workplace:

The manufactured machine is made from quality materials and has robust design. During surface treatment, do not touch the working tool and moving parts of the mechanism with your hands.
Work on homemade grinding equipment should be in protective glasses.
For woodworking, you cannot use discs designed for metal processing, as they have a different surface structure.
Before starting work, it is important to check the serviceability of the design details.
The use of a protective cover for grinding wheels increases the safety of work.

A simple, homemade do-it-yourself belt sander: step-by-step manufacturing photo with a description.

With the help of this tape machine, you can easily and quickly perform grinding, form bevels on knives, sharpen axes and many other tools. You can make such a device with your own hands, we suggest you look step by step photos for the manufacture of grinding machines.

Materials for manufacturing:

– electric motor 220 V, 2 kW, 2800 rpm;
- square steel pipes;
- Sheet steel;
- bearings;
- nuts and bolts;
- spring;
— shock absorber trunk lid cars;
- wheels (you can carve them yourself out of wood).

The base of the machine will be made of thick sheet steel.

The manufacturing process is shown below. telescopic rack, it will be made of two square pipes. We cut off the necessary pieces of pipe on a cutting machine or grinder. Next, we weld a wider pipe vertically to the base. We use the corners to weld the pipe strictly vertically.

The manufacture of 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 assembly is made of steel plates, the process of assembly and operation of this assembly is shown in more detail in the photo. There is nothing complicated in manufacturing, we cut blanks, drill holes, cut threads where required.

This adjustment assembly is then assembled on a long steel plate that is welded horizontally to the post.

We install and fix the electric motor on the base. As a tensioner for the emery belt, this design uses a shock absorber from the trunk of a car.

Next, we install the wheels, you can turn them yourself out of wood on the simplest lathe. The drive wheel is fixed on the motor shaft, and the driven wheel rotates on the bearing. You should also install auxiliary plates under the emery tape, one plate is mounted vertically, the second horizontally.

Every person who has had to deal with wood processing knows the importance of the final polishing of the finished product.

This also applies to holders for various agricultural implements, and wooden furniture, and building elements (doors, windows, window sills) and any other wood products. Sanding allows you to remove burrs, as well as bring smoothness and shine to the wood.

Of course, grinding work can be done with a regular piece of sandpaper or a special attachment for drills or angle grinders. But this takes a lot of time and does not ensure the ideal shape of the product. Therefore, for such purposes, various grinding machines were created.

Most often in living conditions and in the conditions of small-scale production they use a drum grinding machine, the device, the principle of operation and the possibility of making it with our own hands, we will consider in this publication.

1 Drum grinder - device, principle of operation

The drum grinder got its name from the rotating cylinder - the drum, which, in fact, performs the function of grinding.

In addition to the grinding itself, which allows you to remove burrs and give wooden surface perfect smoothness, such devices also perform a calibration function. Grinder drum or any other type allows you to adjust wooden detail under the right dimensions with millimeter precision.

This machine is used for finishing sanding and grading of flat and long wood products, such as wood panel surfaces, chipboard, fiberboard, etc., doors, window sills, and so on. The use of such a device for processing cylindrical parts is not possible.

1.1 Main components

Drum grinder appearance and does not have a set of basic components fundamental differences from any other machine.

AT basic equipment Such a device includes the following elements:

The bed is the part of any machine to which all other elements are attached.
The engine performs the function of driving the moving parts of the machine. Most often, drum sanders for wood are equipped with two motors. One rotates the drum itself according to the principle of a drill, the second sets the feed tape in motion.
Grinding planer drum, on which the emery belt is wound and attached. It is necessarily equipped with a tensioning mechanism, with the help of which, when the tape is heated, it is automatically tensioned. The rotating drum with sanding belt directly smoothes the woodwork.
Feed drum with conveyor belt. This part of the woodworking machine makes its own wiring wooden product on the grinding drum. Thanks to flat surface conveyor and the same distance from the belt to the drum over its entire plane, the product is evenly adjusted to the desired dimensions.
The mechanism that regulates the speed of the conveyor belt.
Fixing racks of the grinding drum, equipped with a ruler. The ruler and screw fixation on the racks allow you to set the required thickness, under which the product must be adjusted.
The protective cover covers the grinding drum to prevent injury during operation.
Machine for removing dust and chips.

1.2 How it works

Such a grinding machine works on the principle of a drill. Its grinding part rotates the engine at high speed - an average of 2000 rpm.

The sander can have different weights, different sizes, sanding drum length, conveyor belt length and width, maximum and minimum drum installation height, etc.

The choice of technical parameters of the device depends on the functions for which it is purchased.

After installing the machine, you need to calibrate the grinding drum to avoid eccentric rotation and unnecessary vibrations. In addition, a non-centered drum will not be able to clean the products evenly.

To do this, we take two beams of the same height, install them on the feed belt, lower the drum on them and fix them in this position. Next, set the height of the mechanism, depending on the size of the part to be ground.

We turn on the installation. For the first pass it is better to set the minimum speed of the feed belt, for the final - the maximum - 3 meters per minute.

The grinding drum should gain momentum, like a drill. After that we put wooden beam to be processed onto the conveyor belt. The passage of the beam under the drum occurs automatically.

We repeat this action right amount times, until our part comes into the desired shape and acquires the specified dimensions.

If the sides of the product have different size, the height of the drum must be adjusted for each change in parameters.

2 Types of machines

If we talk about grinding machines in general, their classification is based on two parameters: the scope and the functions performed.

According to the field of application, the machines are:

circular grinding machines. Are intended for processing of the details having round section;
surface grinding. Their task is to grind flat parts. The drum machine also belongs to this type;
internal grinding. With the help of such mechanisms, the internal surfaces of the product are processed. Drills are often used for this purpose;
specialized. Designed for processing complex surfaces - threads, grooves, teeth, etc.

Various machines can perform different functions:

pruning and cleaning;
sharpening;
grinding.

2.1 We make a drum machine with our own hands

It is difficult to make a drum grinder for raw wood with your own hands, but it is quite possible.

To do this, we take a list necessary elements and looking for suitable material and spare parts.

And so, we need:

Bed. For these purposes, any stable workbench or table is suitable, to which other elements of the machine can be screwed. It is better if the bed is metal. If you have to use wooden structure, it needs to be qualitatively strengthened with your own hands.
Electric motor with a power of 200-300 watts. The speed should be 1500-2000 rpm. Better if it is single phase asynchronous motor. For these purposes, a mechanism from an old washing machine is suitable (in this case, we take pulleys with a belt from it), drills, grinders, etc.
Sanding drum for wood. This is perhaps most important and most hard part machine, on which the quality of the work performed will depend. We will talk later about how and from what to make a home-made grinding drum with our own hands.
Drum stands. The device that fixes the drum and regulates its height can be made of wooden beams. The height adjustment mechanism can be made by hand in two versions. First option - through holes on the racks through which the drum will be attached. This option is simpler, but it only allows you to work with a fixed adjustment step of about 1 cm. The second option is long screws mounted perpendicular to the drum. In this case, by tightening the screws, we will be able to raise the grinding device, releasing - to lower it. In the second variant, height adjustment is possible with an accuracy of up to a millimeter.

We will not make a conveyor belt with our own hands. It's possible, but not necessary. Submission for homemade machines is usually done manually.

2.2 Making a drum

Before proceeding with the manufacture of the drum itself, you need to clearly understand what functions our machine will perform. The point is that what smaller size cylinder, the easier and faster it will be rotated by the engine from the drill.

To make a grinding drum, we need a piece of anything that has a cylindrical shape, the desired length and diameter. It can be a wooden beam with a round section, a PVC pipe, metal pipe and much more.

We will consider as a material pvc pipe for making a drum with your own hands.

We take the segment of plastic pipe that is required in size. We will also need metal pin acting as an axis, wooden or plastic plugs that match in diameter with the inner diameter of the pipe, self-tapping screws, rubber, glue.
We take the plugs and make holes in them that correspond in diameter to the thickness of the rod.
Holes in the plugs must be exactly in the center. The slightest eccentricity of the drum will lead to incorrect operation of the machine.
We tightly plant the plugs into the pipe and fix it with self-tapping screws.
Insert the pin into the holes in the plugs. The axis should protrude from the cylinder by 2-3 cm on each side. It is she who will act as an attachment to the adjusting racks.
We glue rubber on the drum. To her it will be easier to attach the sanding belt.

2.3 Assembling the machine

To assemble the machine you need:

Install the racks on the frame.
Attach the drum to them so that the height of its rise can be adjusted.
Connect the motor to the drum using a belt or chain drive.
You can get to work.

2.4 Homemade drum sander (video)

Homemade disc grinder made by a craftsman with his own hands: detailed photos production with description.

I decided to make myself in the garage — a grinding machine. Found in the bins old engine Soviet production, power about 1 kW, 1420 rpm.

So I completely disassembled this electric motor and cleaned it of rust, sandpaper and files.

On the junction box the nut was lost, I had to put the nut from the adapter on the plastic pipe.

Polished the case with GOI paste.

Then I cleaned and painted the casing, used a primer, paint and varnish.

I ordered a plan-washer from a turner. Outside diameter- 100 mm, 4 holes and one in the center, all with a diameter of 4 mm, the thickness of the washer itself is 4 mm. However, it turned out that the plan-washer is put on the engine shaft with at least a little effort, but by hand, but it is necessary that with a slight interference. The foil does not fit, too tight, so I applied a layer of primer.

Then he made a working surface - a chipboard disk. Bought 2 pieces Chipboard thickness 16 mm, for large sandpaper and small. 5 or 6 layers of PF-170 varnish were applied around the circle.

To accurately install the disc, I did this: in the center of the plan-washer (into a pre-drilled hole during manufacture), I drove a short nail from the nail, and aligned it with the drilled hole in the center of the disc, marked and drilled 4 holes in the disc for fastening.

He drowned the screw heads and put them on epoxy resin so that they do not rotate when tightening the nuts.

The bed was made from the door of an old cabinet.

Installed capacitors.

I glued sandpaper No. 60 to the disk with PVA glue. Maximum size disk that can be used - 330 mm.