Do-it-yourself vertical grinding machine. DIY wood sander

Nowadays, there are no surfaces that are not smooth. Smoothness is achieved through various grinding devices. Professional equipment costs a lot of money and not everyone can buy it, moreover, such machines have a fairly high weight and dimensions.

Fortunately, the skilful hands of our country have adapted to produce analogues of equipment for such a modest budget. The grinding machine also did not stand aside and was subjected to a modernization of manual craftsmanship. It is with this homemade machine that we will continue to get acquainted.

There is a huge amount of sanding equipment that makes any wood surface very smooth. It is a frame on which a special frame with an electric motor is located (motors of washing machines are used for homemade products) and a mechanism. The mechanism itself, in turn, includes shafts, pulleys and an abrasive belt.

Application area

They are used in all industries where wood is processed. Often, any draft products have an uneven and rough surface. Such blanks cannot simply be painted and put up for sale or installed anywhere. Therefore, for further processing of wood, all its surfaces can be sanded.

Grinding machines are also used for processing sags and chamfering, rounding corners. In addition, the grinding tool gives any surface smooth alignment and calibration.

Types of wood sanding machine

Depending on the surface to be treated, the following types of grinders are distinguished:

Belt sander

This equipment uses an abrasive belt, which is pulled by two shafts. These shafts are driven by an asynchronous electric motor. The abrasive belt does not sag during wood processing, but rests against the working plane, which has a low coefficient of friction. The tape can be placed both horizontally and vertically. The advantage of this equipment is the processing of long workpieces.

Universal grinding unit

In this case, the machine has two working grinding surfaces. One is tape surface and the other is circular (disk). This universal machine was created for the convenience of working on it. By the way, such equipment will significantly save the budget. In such a device, only one engine is used. Based on this, when working on two working surfaces, the load on the motor will not increase much.

Drum grinding tool

In this case, the abrasive tape is wound on two rollers in a spiral manner. Under the rollers is a tabletop with a smooth surface. The gap between the tabletop and the rollers is adjustable to the required distance. With the help of such a machine, it is possible to calibrate the surface of a wood blank.

Disc grinding tool

The working area of ​​this equipment is an abrasive wheel. A circle with Velcro is attached to the axis of the electric motor, on which the abrasive is attached. After starting the motor, the abrasive wheel rotates around its axis, thereby carrying out grinding. This type of machine has the ability to adjust the processing speed, and the number of revolutions of the axis will not decrease.

Each of the four types of machines can perform certain operations. Now that we have an idea of ​​what the grinding equipment looks like, it's time to disassemble the design of the machine.

In addition to the above machines, there are also portable ones. grinders. And that's not all, so as not to spend money on machines, people came up with grinders from a drill, from Bulgarian. The fact is that nozzles are fixed on these tools and the same grinding is carried out.

Tip: If you still decide to purchase a factory grinder, then decide in advance on the work and loads that your machine will undergo, and only then make a purchase. The same applies to homemade tools.

Motor power calculation

Important! Before creating any homemade brainchild that performs grinding functions, it is extremely important to correctly calculate the power of the electric drive. After all, if the motor power is weak or vice versa strong, then you cannot do any work.

The calculation of power is carried out according to a special formula, which belongs to the category of complex mathematical calculations.

The formula looks like this

P=q*S*(K+k)*U/1000*n

Where each designation means the following

1. q - Means the pressure of the processed wood part on the plane of the abrasive cloth (N / square centimeter).
2. k - The index of friction of the wrong side of the abrasive on the working surface.
3. n - The efficiency of the entire system.
4. K - An indicator of the working plane of the abrasive relative to the workpiece. The priority is the density of the tree and its graininess. The limits of this indicator range from 0.2 to 0.6.
5. S - The area of ​​the workpiece that is in contact with the abrasive, measured in square centimeters.
6. U - The speed of rotation of the abrasive, measured in meters per second.

When you calculate the required power of the electric drive of your future unit using the formula, you can safely begin to assemble the machine as a whole.

It's time to get acquainted with the design of a homemade machine. Blueprints all four types of equipment can be found in free access for viewing and download, as well as download all kinds of Photo scheme. As an example for visual study, consider a belt sander.

The design of the machine and its schemes

Any assembly of home-made equipment begins with the construction of a frame or foundation for future machine equipment. This can be done with a metal material, or with a wood material. The following dimensions of the frame are used as standard 500 mm x 180 mm, while the thickness should be 2 cm.

After making the base, you can proceed to the next steps. An asynchronous motor can be installed in several places so that its operation is complete. Prepare a plane on the bed itself or make a platform for the motor, which will be attached to the end of the bed. The other side of the bed is designed to accommodate the shaft, with a pulley for a belt and rollers for an abrasive belt. The tape itself is installed with a slight slope. This is done so that the abrasive smoothly and gently comes into contact with the machined plane of the workpiece.

Tip: Before installing the abrasive strip on the rollers, it is necessary to wrap a thin strip of rubber around them. This will reduce strip slip during operation.

As we can see from the diagram and drawing, the design of the grinding equipment is quite simple. All varieties of these machines are assembled according to the same scheme.

Tip: In the process of assembling your future grinding unit, you must comply with all the necessary dimensions, and you must also calculate all the parameters very seriously.

When the design is familiar to us, we can proceed to the assembly process.

The assembly process of the grinding machine

To assemble the grinding tool, you will need the following items:

1. Wood board.
2. Wooden bars or metal profile pipe.
3. Ball bearings.
4. Electric motor.
5. Rubber strap.
6. Rubber belt.
7. Metal pulley.
8. Self-tapping screws, fasteners.
9. abrasive element.
10. Working tool (drill, grinder, screwdriver, jigsaw, etc.).
11. Welding machine (if the frame structure consists entirely of metal).

After we have decided on the materials and working tools, we can begin to assemble all the parts and elements into one mechanism. For this, the frame is assembled. It can be metal (consist of a metal-profile pipe) or wood (consist of wooden bars and solid wood).

When the frame is ready

You can start installing the motor. The motor power must be at least 2.5 kW and not more than 3 kW, with the engine speed between 1200 and 1500 rpm. A pulley for a belt is installed on the motor shaft. The motor is mounted on one side of the frame. Motors are often used from washing machines used at home.

On the other side

A shaft with bearings is located, on one side of which a pulley is fixed, and on the other side a roller, an abrasive belt will be put on it in the future. Shaft pulley and motor pulley must be in a flat horizontal plane. The belt tensioner should be located in the same area.

Coming from wood

Either a stand is constructed from plywood or metal, on which the remaining rollers will be placed and an emery tape is worn. There must also be a tension mechanism. In addition, the presence of a working bar is mandatory, on which the abrasive belt will rub.

On the frame, as a rule, from the end, a start button is installed. The electrical circuit of the machine must be grounded.

After that

Once everything is done, you can make the first start and configure the equipment properly. When the setting is done, the first workpiece is run and the result of the work is checked. If everything worked out, it means that you did everything right.

For visual clarity and a complete understanding of the entire assembly process, you can download video instructions.

General feedback and summing up

As a rule, there are only positive reviews about this type of equipment on the Internet. Indeed, when in everyday life it is necessary to give this or that wooden thing a smooth surface, then the presence of grinding tools is indispensable.

Video reviews

Video review of a homemade grinding machine:

Video review on the choice of grinding equipment:

Video review of the belt sander:

Video review of eccentric sanders:

I have been making knives for several years now and always use 2.5 x 60 cm and 10 x 90 cm belt grinders in my business. For a long time I wanted to get another one with a 5 cm tape, as it would make my work easier. Since such a purchase would be an invoice, I decided to make it myself.

Problems in the design of the future machine:
Three limitations had to be overcome. Firstly, there was no tape 10 cm wide at the place, it could only be ordered online. For me, this option seemed not very acceptable, since there is no greater disappointment than to find that the tape has worn out and needs to be replaced, and you have to wait a week or two for a new one to arrive. Secondly, there was a problem with the rollers. I searched but couldn't find any suitable 10cm tapes. Thirdly, the motor. A belt sander needs a fairly powerful electric motor, and I didn't want to overspend on this project. The best option for me was to use a used motor.

Solutions to design problems:
The first tape problem found a simple solution. Since the 20 x 90 cm belt was freely available in hardware stores at a reasonable price, I could make two 10 cm from it. This imposed restrictions on the size of my machine, but due to cost effectiveness, this option was the best. The second problem was solved using a lathe. To do this, I watched a video on the Internet, and realized that I could make the videos I needed myself. With the motor, the task was more difficult. I had several electric motors in the garage, but for some reason I had to abandon them. Finally, I settled on an old tile cutter that had a 6 amp electric motor installed. At that time, I realized that this power may not be enough. But since the work was at the experimental stage, I decided to first achieve a working version of the machine, and the motor can be replaced later. In fact, for a small amount of work, the motor is suitable. But if you are going to be doing more intensive sanding on it, I would recommend a 12 amp minimum.

Tools and materials

Tools:

• Angle grinder with cutting discs.
• Drill and drills.
• Wrenches for 11, 12 and 19.
• Lathe.
• Vice.

Materials:

• Electric motor (6A minimum, or 12A recommended).
• Various bearings.
• Nuts, bolts, washers, lock washers of various sizes.
• Metal corner.
• Sanding belt 20 cm.
• 10 cm pulleys.
• Powerful spring.
• Steel bar 4 x 20 cm.
• Timber 2.5 x 10 x 10 cm made of wood or MDF.

Electric motor for machine

I had a choice of several motors, but the electric motor that was on the tile cutter had a more suitable casing. To some extent, working on the machine was like an experiment, because I was not sure about the sufficient power of the motor. Therefore, I settled on a modular solution with a belt frame as a single element that can be removed and rearranged to a more powerful base. The speed of rotation of the motor suited me quite well, but I was worried that 6 A would give weak power. After a little testing, I saw that for simple work, this electric motor was suitable, but for more intensive work, you need to choose something more powerful. When designing your machine, pay attention to this point.

As I mentioned, the motor housing was very suitable, as it allowed the creation of a vertical machine that would be easy to move.

First you need to release it by removing the desktop, saw, protection, water tray, leaving only the electric motor. Another benefit of using this motor was the threaded core and nut to hold the saw in place, allowing the pulley to be mounted without the use of a key (what a key is, I'll explain later).

Since I had a pulley that was too wide, I decided to use the large pressure washers that usually secure the saw, turning one upside down so that there is a wedge-shaped groove between them. I found that the space between them was too narrow, and to widen it, I put a lock washer between them. The advantage in this method is that the pressure washers have a flat edge, which is fixed with a flat edge for simultaneous rotation with the core.

Belt

The drive belt I used was 7 x 500mm. A standard 12mm can be used, but a thinner one is more flexible and will put less strain on the motor. He does not need to rotate the grinding wheel.

Belt sander device

The device is simple. An electric motor drives a belt that rotates a 10 x 5 cm "master" pulley that drives the abrasive belt. Another pulley 8 x 5 cm is located 40 cm above the main one and 15 cm behind it and is mounted on a bearing. The third 8 x 5 cm pulley rotates on a lever and acts as a tension roller, holding the abrasive belt tight. On the other side, the lever is attached to the frame by a spring.

Determining the drive type

The main issue was to rotate the main pulley directly with an electric motor or with the help of an additional pulley and a drive belt. First of all, I chose a belt drive because I wanted to be able to change the engine to a more powerful one, however, there was another reason. When you do intensive metalworking, there is a risk of running into some problems. Belt drive in such cases will slip, while direct drive will create big problems. With a belt, the device will be more secure.

Frame fabrication and installation

It is important to mention that using a metal angle as a frame can have both advantages and disadvantages. The obvious advantage is that it is convenient to assemble it, like a designer in childhood. But the main drawback is that it is strong only in two directions, but weak when twisting. So, you need to take into account this weakness and calculate what torque can be transmitted from the pulleys to the frame, and compensate for it with the help of additional jumpers.

Cutting:
You can use a hacksaw to cut the corner, but an angle grinder with a cutting disc will make the job faster. After cutting off all the elements, I would recommend sanding all their sharp edges so as not to cut yourself during assembly. Holes can be drilled with a conventional drill and cutting fluid.

Main roller

The main roller is the most important part of the project, as it receives torque from the motor and transmits it to the belt. I used an old bushing to mount it, but I recommend using a bearing instead. The bushings do their job, but they constantly overheat and require regular lubrication. Moreover, they can scatter dirty grease, which is annoying during operation.

Shaft:
There are threads on the sides of the shaft with different directions so that the fixing bolts do not unscrew during rotation. If you cut off the threaded side, as I did, leave the one that goes counterclockwise, otherwise you will have to make a lock bolt (I will describe how to do it later) and a cotter pin. The main pulley will be put on the cut edge.

Pulley:
Continuing the theme of reuse, I found an old pulley from another project. Unfortunately, I prepared it for the threaded pin that it was supposed to hold on, but, in fact, this is not a problem. In this pulley, I made a rectangular cutout. Then, using an angle grinder, I cut a groove into the end of the shaft. By placing the key in the hole formed by the groove of the shaft and the rectangular cutout of the pulley, I securely fixed them relative to each other.

Production of rollers for a grinding machine

I made the rollers out of several pieces of hardwood 2.5 cm thick. But you can use MDF, plywood or other material. When laying the layers, it is necessary to make sure that the fibers are perpendicular, this will give the rollers additional strength and the layers will not split.

It is necessary to make three rollers: the main roller, the upper roller and the tension roller. The main roller is made from two 13 x 13 cm pieces 2.5 cm thick. The top and idler rollers are made from two pieces of wood measuring 10 x 10 cm.

Process:
Start by gluing pairs of 13 cm and 10 cm pieces of wood, clamping them with clamps. After the glue has dried, cut the corners with a miter saw, then find the center of each piece. Fix them in a lathe and machine them until they measure 5 x 10 cm and 5 x 8 cm.

Top and tension rollers:
Next, you need to install the bearings in rollers measuring 5 x 8 cm. Select a core or spade drill, and drill a recess in the center to the width of the bearing. The inner ring of the bearing must rotate freely, so a hole must be drilled through the roller through the inner ring of the bearing. This will allow the bolt to pass through with a minimum opening.

Main video:
This detail is done a little differently. There are no bearings on it, however, if the shaft is less than 5 cm out of the roller, it will be necessary to grind the roller in width. Measure the diameter of the shaft and drill the same hole in the center of the roller. Try to insert the shaft, it must hold tight, otherwise the roller will shake.

Bolting rollers

Next, you should fasten the two halves of the rollers with bolts, you should not rely only on glue. Remember that the bolt heads must be sunk into the wood as the roller rotates in close proximity to the frame.

Tension lever

The lever is made of a metal bar measuring 10 x 30 x 200 mm with rounded edges. It needs to drill fairly large holes, so I recommend using a drilling machine and a lot of lubricant for this. You will need 4 holes in total. The first is at the pivot point. It is not in the center of the bar, but 8 cm from its edge. The second hole will be on the edge closest to the pivot point. It will serve to attach the spring. Two additional holes must be drilled at the opposite end, approximately 5 cm apart. They should be a little wider in diameter as they will be used for the setup I'll cover next.

When all the holes are made, you can fix the shoulder on the vertical corner between the top roller and the base. The end where the spring will be attached is directed towards the main roller. It should rotate freely, so I recommend using two nuts for fastening, not completely tightening the main one, and using the second one as a lock nut.

Installing rollers

The top roller is fixed statically and must be clearly in the same plane as the idler roller and the main roller. You can do everything by eye, but I recommend checking everything well with a level. To align the roller, you can add a washer, or, if it is not enough, a bolt. They are inserted between the frame and the roller.

It is not necessary to fully install the tension roller. Still need to make a stabilizing device.

Tape stabilization

Wear on the rollers or an uneven surface can cause the abrasive belt to gradually come off the rollers during operation. The stabilizer is a device on the idler that allows it to be angled to keep the abrasive belt centered. Its arrangement is much simpler than it looks and consists of a fixing bolt, a little free play on the idler pulley and an adjusting bolt.

Drilling holes in bolts:
For this purpose, I made a device, in the form of a wedge-shaped cut in the board, which will help to hold the bolt in place at the time of drilling. You can do it manually, but I don't recommend it.

fixing bolt

A fixing bolt is a simple bolt with a hole drilled in it, and which is installed on the bar through a wide hole that is closer to the pivot point of the lever. Since it is located between the lever and the roller, its head must be ground off so that the roller does not cling to it. The bolt must be fixed as shown in the figure.

Bolt holding roller

It needs to be loosened a little so that the tension roller has a little play. But so that it does not unwind, you need to make a castellated nut. To do this, you just need to make cuts on the edges of a regular nut so that it looks like a crown. There will be two drilled holes in the bolt itself: one for the adjusting bolt, and it will be aligned with the hole of the fixing bolt, and the other for fixing the castle nut with the cotter pin.

Bolt for setting:
Once the idler is in place, the adjusting bolt can be installed, which will pass through the holes of the fixing bolt and the bolt on which the idler rotates. The system works by tightening the adjusting bolt, causing the idler wheel's axis of rotation to shift its angle of rotation outward, thus causing the belt to move closer to the mechanism. A spring at the other end of the arm adjusts the tension in the opposite direction. I recommend securing the adjusting bolt with a locknut, as vibrations can loosen it.

Note: It is possible to add a spring on the back of the idler, but I have not found any reason why this is worth doing. A slight advantage is that in this way the roller will have less play. But I will add that I did not do this, and I did not have any problems.

Completion of work on the manufacture of the machine with your own hands

When everything is done, you need to check all the bolts again, and make sure that the stabilization mechanism is assembled correctly. Then you need to turn on the device for the first time, which can be scary. It's like driving a car where the steering wheel and transmission don't work. I recommend turning the motor on and off for a very short time so that the machine does not spin at full speed.

In fact, the hardest part for me was the spring setting. If you pull too hard, the tape will not be able to rotate ... Too weak - and it is impossible to hold it, it flies, which in itself is dangerous.

Ready!

That's all. You should end up with a decent medium power belt grinder that can be converted to a more powerful one if desired.

Hope you enjoyed this tutorial. Thank you for your attention.

Grinding equipment is used for finishing parts. The machine performs finishing technological operations in the manufacture of wood and metal products. A significant plus of such a device is the possibility of self-assembly. A home-made unit is somewhat inferior in performance to factory models, but it will cost much less.

The working principle and characteristics of the grinding machine

Grinders differ from each other in design and scope. The general characteristic of the tool is a similar principle of operation. The working mechanism rotates and the abrasive material grinds the surface of the part.

When choosing finished equipment or making a machine with your own hands, it is necessary to take into account the main characteristics of such equipment:

1. Power. When using the machine at home, a power of 400 watts is enough. To perform production tasks, high efficiency and productivity of the unit will be required - at least 1 kW.
2. The speed of rotation of the working mechanism. The grinding abrasive element performs up to 3000 revolutions per minute per minute. The higher the rotation speed, the better the processing quality. Experts recommend using units with an indicator of at least 500.
3. processing area. This parameter is determined based on the scope. The larger the width of the drums or sanding belt, the larger the products will be sanded.
4. Device dimensions. Dimensions are an important parameter, which largely depends on the area of ​​\u200b\u200bthe workshop or workshop. When self-manufacturing, the machine is designed so that after its installation there is enough space for placing tools, blanks, consumables and other equipment.

Features of different grinding machines

Depending on the configuration of the abrasive unit, the following types of machines are distinguished.

tape device- grinder. The machine is equipped with an abrasive belt, which wears out over time and requires periodic replacement. Using the unit, you can remove a layer of rust from metal, correct the dimensions of the product in some planes, clean and shape wooden parts.

Positive aspects of tape machines:

• universality;
• small dimensions and light weight;
• the possibility of self-production;
• Adjustable belt length for sanding and polishing items of various sizes.

Advice. When equipping belt grinding equipment, it is better to choose graphite abrasives - they are the most wear-resistant.

drum machine works on the principle of a drill. The grinding part of the device rotates from the engine at a speed of about 2000 rpm. The main purpose is the calibration of flat long workpieces. A drum-type unit is more difficult to manufacture, but such a home-made wood grinding machine will allow you to process slats, shield surfaces made of MDF, chipboard, veneered material and wood.

disk device(dish machine). It is quite possible to assemble the unit yourself, as it has a simple device. Disc machines are characterized by the following features:

• compact dimensions and ease of use for domestic purposes;
• good performance with a powerful electric motor;
• the possibility of polishing workpieces of cone-shaped, spherical and cylindrical shape.

Combined grinding machine - a combination of the functions of flat and cylindrical grinding equipment. One device is equipped with a grinding wheel and an abrasive belt. This option is best suited for small workshops and garages, where the installation of two units at once is problematic.

Homemade belt sander

Accessories for belt type devices

Homemade grinding machine for metal or wood has the following design:

1. The bed is the base of the machine. The working base of the structure is usually made static - it is screwed to the floor. Sometimes the equipment is additionally equipped with wheels for ease of movement.
2. Working platform for the subsequent placement of the electric motor.
3. Electrical engine. As a rule, the drive is installed near the larger diameter drive roller.
4. Leading and driven tension roller. In self-manufacturing, you can use improvised materials made of metal or high-density wood. To prevent the tape from rolling off the shaft, the diameter of the central part of the rink should be 2 mm smaller than at the edge. To prevent slippage of the tape on the drums, it is desirable to wind a thin layer of rubber.
5. The belt tensioning mechanism consists of a lever and a clamping spring. The lever is fixed to the frame and the driven tension roller.

Important! For processing steel or wood, paper-based or fabric-based tapes are used. Tape width - 5-31 cm, length - from 11 cm, grain size from R-80.

Manufacturing technology of the belt assembly

Homemade belt grinders for wood or metal can be made from the following materials:

• electric motor with a shaft speed of about 1300-1600 rpm;
• steel pipes not less than 2 mm in thickness;
• corners with a section of 50 * 50 * 5, 25 * 20 * 1.5 - the number is determined by the dimensions of the equipment;
• magnetic stand for fixing metal blanks;
• bearing supports, ball screws;
• shafts for fastening the tape;
• rail guides.

Work sequence:

The described type of machine is more suitable for grinding flat metal workpieces.

Homemade drum sander

Drum-type equipment device

The drum grinder belongs to the class of calibration models. The main element of the device is a grinding drum that gives smoothness to wooden surfaces.

Elements of the basic configuration:

• bed;
• engine;
• planer drum with emery tape;
• feed drum with conveyor belt;
• mechanism for adjusting the speed of the drum;
• stands for fixing the position of the grinding drum;
• protective cover;
• dust extractor.

Homemade wood grinder: drawing

Step-by-step instructions for creating a machine

Stage 1. Motor selection. An old engine from a washing machine will do. Remove the pulleys, belt and electrical part from the equipment. It is desirable to give preference to an asynchronous single-phase electric motor of 200-300 W, 1500-2000 rpm.

Stage 2. Drum making. To create it, a PVC pipe, wooden rings and other improvised items are suitable. A PVC drum kit is made as follows:

1. Cut a piece of the desired length from a plastic pipe with a diameter of 10 cm.
2. Prepare end caps from wood with holes in the center of 2 cm.
3. Fasten the end elements to the pipe with screws.
4. Pass a steel bar 15-20 mm thick through the hole.
5. Stick a rubber sheet on top of the pipe.
6. Using a stapler, fix the sandpaper on the drum.

Stage 3. Preparation of the desktop and bed. The body is made of wood:

1. “Cut out” the wooden canvas into side panels (2 pcs.), spacer, details of the worktop (base and movable component).
2. Assemble and strengthen the structure with a cross member. The internal spacer will additionally act as a support for the adjustment screw.
3. To be able to control the course of the working surface, its movable element is fixed with a piano loop to the base. An adjusting screw is installed on the feed side of the workpiece.

Stage 4. The assembly is performed in the following sequence:

Stage 5. Fixing the protective cover and commissioning.

DIY grinding tools

In addition to overall machines, small practical devices for polishing metal products or grinding some parts can also come in handy in everyday life. Many of them are quite possible to do with your own hands.

Mini grinder and "polishing" for metal

A mini-grinder is useful for home craftsmen and lovers of alterations - the device is used for high-quality cleaning of surfaces before soldering. The necessary details can be taken from an old Soviet tape recorder.

Glue fine-grained sandpaper onto a wooden round plate. This will be the working part of the grinder. To start the machine, you will need a small motor with a shaft diameter of 1.5 mm and a button. Solder the start button to the electric motor.

A 7 V AC adapter is suitable for power supply. One contact of the adapter is soldered to the switch leg, and the second to the electric motor. Fill the soldering points with hot glue. After it dries, wrap the body with heat shrink or electrical tape. The final stage is the fixation of the working grinding element.

Homemade disc grinder

A disc grinder of low power is useful for turning small-sized wooden products. For the machine shown in the photo, a 90 W three-phase transformer was used, launched through a capacitor. An engine with a speed of 2750 per minute is connected in a triangle with a starting capacitor and reverse. Connections are soldered and hidden in heat shrink.

The base is fixed on four steel rods - if necessary, quickly installed and removed. A mandrel for M14 is attached to the shaft, it is possible to install different nozzles from a grinder.

Safety precautions when working on homemade grinding equipment

When performing work on the machine, it is worth adhering to a number of rules that will help protect yourself and others from possible injuries:

1. Do not touch work surfaces and moving parts with your hands.
2. Protective goggles must be worn during operation to prevent particles of hot scale and abrasive from getting into the eyes.
3. Before starting work, it is necessary to check the reliability of the fastening of the shafts, tape and disk.
4. It is important to control and check the integrity of the wire braid. If the slightest malfunction is detected, work must be suspended.
5. A protective cover must be used. The element somewhat narrows the view, but greatly increases the level of security.

Homemade vertical grinder: video

A grinding machine can be used to process various workpieces or products. It is necessary to perform the finishing operation of surface treatment. Machines of this type are widely used in the woodworking industry, but can also be used at home. If necessary, you can create an emery grinder with your own hands for wood. Consider how you can independently make a belt grinder, and what it happens to be.

If desired, you can also make a metal grinder with your own hands, which differs from the model intended for wood processing only in the type of abrasive belt installed. Design features of the belt grinder Let's take a look at the points below:

1. The drawing provides for the presence of two drums that pull the abrasive belt and set it in motion. One of the drums is the leader, the second is the slave.
2. A do-it-yourself drum sander for wood is created by installing an electric motor as a drive. Modern motors can have different speeds of rotation. Homemade models can have interchangeable pulleys and a V-belt drive. By changing the diameter of the installed pulleys, it is possible to change the speed of rotation of the abrasive belt.
3. Some models of surface grinders have a belt tension system. This greatly simplifies the grinding of workpieces and products.

In general, it can be said that the emery equipment of this type has a simple design, which will have high reliability.

Principle of operation

A homemade metal grinding machine may not be inferior to the industrial version. Considering the principle of operation of such a device, note the following points:

Processing of blanks and parts is carried out by pressing them against the abrasive belt during its movement. The main rotation is transmitted through the drive to the driving drum, the driven one is designed to fix the tape.

homemade model

With a strong desire, you can make a calibrating machine or a disc type of grinding equipment with your own hands. Homemade versions are much cheaper, while productivity can also be high.

To create a grinding machine you will need:

1. An electric motor that creates rotational motion.
2. Rollers, due to which the tape is fixed.
3. A reliable bed that becomes the base.
4. Abrasive belt, due to the movement of which the surface is processed.

Considering the features of creating a grinding machine with your own hands, note the following points:

1. The electric motor will be easy to find. It can be removed, for example, from an old washing machine. For home use, an engine powered by a 220 V network is suitable. You can also use a regular network, but many problems can arise with this.
2. The bed is made independently from thin sheet metal or channels. The connection of individual elements is carried out by welding. A screw connection to create a bed is not suitable due to the fact that vibration can lead to loosening of the connection.
3. Often the electric motor is connected directly to the drive drum. It should be borne in mind that in this case the electric motor is not protected from a sharply increasing load. The driven shaft is mounted on an axle and two bearings. The efficiency of the equipment depends on how freely it will rotate.
4. Inexpensive shafts can be obtained from chipboard. It should be borne in mind that such shaft options are not designed for a large load.
5. It is possible to eliminate the possibility of slipping of the tape on the drums by applying rubber to the surface. To do this, you can use an old tire from a bicycle.
6. Sanding belt can be purchased from a specialized store.

Today you can find a fairly large number of drawings that can be used to create such equipment. They are all about the same. Before doing the work, you should decide on the dimensions of the workpieces and products to be processed.

All materials in any production, in addition to manufacturing, require additional and finishing processing. Vivid examples of such treatments are grinding and polishing of the product. These two types of mechanical action on the surface of the part bring its appearance to perfection. However, everyone knows that in order to perform these operations by hand, it will take a lot of time and effort, and only a very experienced master can ensure even processing. To facilitate this kind of work, a person came up with various devices and mechanisms to help himself. Some of them will be discussed further.

General purpose and types of machines

The machine is intended for the final processing of parts and workpieces made of different materials by exposing them to a surface with an abrasive or diamond coating. The machine, its constituent mechanisms and fixtures allow maintaining the accuracy of size and shape, and also ensure the creation of an ideal surface of a part or workpiece.

With the help of the machine, you can process flat parts, surfaces outside and inside, parts of various geometric shapes, grind or polish threads and gear teeth. According to their characteristics, grinding machines are divided into:

• Cylindrical grinding.
• Internal grinding.
• Centerless grinding.
• Surface grinding.
• Special machines (for grinding threads, gears).

Grinding process

Grinding is the process of removing the top layer from the surface of the workpiece using abrasives or diamond grit. They are assembled into a common mass on the working surface and fastened with a binder. They eventually form a grinding wheel or belt.

During operation, the abrasive surface is given a circular motion by means of an electric motor. When the surface of the workpiece comes into contact with the abrasive, the machining process takes place. There is a common belief that grinding with abrasives is friction processing. However, this is not true.

Each abrasive particle has sharp edges, when touched with a material (metal, plastic, wood, stone) it works like a cutting tool and removes chips, like a milling cutter or a drill. Given the considerable speed of rotation of the grinding wheels, as well as the occurrence of chips as a grinding product, it is necessary to take into account the possibility of injury by this very chip.

Safety measures during work

When working on the machine, the following safety precautions must be observed:

Necessity at work and at home

Today, in production shops, grinding machines are used all the time. Depending on the scale of production, both one machine and all its varieties in terms of complexity and dimensions can be installed.

However, there is always a use for this equipment in everyday life. Some - in the garage there is a bench sander for metal processing. Others have several wood sanders of different design installed in their workshop. The third - in possession is a universal, combined machine. There are power tools for manual grinding: drum type, belt sander, band saw, small machines or large machines. And they are all in demand.

There is a fairly wide range of all kinds of similar equipment from many manufacturers on the market. And their prices are quite reasonable. But these are general purpose machines. And if a person is engaged in his own business, or he has a hobby, then a machine of special specialization is needed. Here the price is already rising several times.

For this reason, or based on their own desires, many craftsmen make homemade products. Mainly for processing wood, plastic and metal, less often for cutting and grinding stone. And, in general, this is correct. After all, even a simple sharpening of kitchen knives is easier and faster to do on a machine than manually using a whetstone. The benefit of creating a home-made machine for wood with your own hands is also its very simple design.

It is not difficult to assemble a do-it-yourself grinding machine for wood. In the people it is also called simply - emery.

The main component is the engine. Surely many of the household there is an old washing machine. Its motor is quite suitable for this purpose. If not, a new engine on the market will be quite expensive, but at any flea market you can find a used one in working condition. The electric motor must be strong from 750 W to 2 kW, not high-speed from 1500 to 3000 rpm, if it is three-phase, then it can always be adapted to 220 V. You will also need thick plywood, self-tapping screws, PVA glue, and a tool, of course.

The task is simple: to make a hard drive on which sandpaper is glued. To do this, we draw a circle with a diameter of 150-170 mm on plywood, if the plywood is thick enough to hide the clamping nut, one blank is enough. If not, we glue two identical blanks with PVA glue. The clamping nut of the motor spindle must be recessed into the disk flush with its working plane.

From the same plywood 15-24 mm, you need to make several parts:

• The frame to which the engine will be attached.
• Feed table with guides for changing the angle of inclination.
• The design of disk protection.
• Base for attaching the entire machine to the workbench.

Protection for the disk can be made in the form of an arch with right angles or truncated. She, like the feed table, is attached to the frame. Of the additional devices, you can install an emphasis-protractor on the feed table, which will allow you to feed the workpiece at a fixed, horizontal angle.

Paying tribute to aesthetics, it is desirable to grind every detail before assembly. But this is optional, but with the serving table this must be done carefully. A smooth surface will ensure uniform and continuous movement of the part along the working surface of the disc.

The purpose of this machine is revealed in its very name - surface grinding, that is, for grinding flat surfaces of parts and workpieces. It can be disk, drum (like a thickness gauge) or tape. At the same time, its working surface can be located vertically, horizontally or regulated.

Individual machine designs are made fully adjustable. But this is individual. Everyone makes home-made machines for themselves, so that it is more convenient to work. Fully adjustable designs are more difficult to manufacture. They have an adjustable pressure of the drum or tape, that is, in other words, there is the possibility of a fixed movement of the working surface along the vertical axis. And the tool rest has a mechanism of movement in two directions, like a cutter holder carriage on a lathe.

From the verbal description it is difficult to imagine what it looks like. And even more difficult to understand how it works. But today we have the Internet. There you can find videos where experienced craftsmen share their experience, explain in detail and show how to make such equipment. Detailed drawings and diagrams are provided with exact dimensions and instructions on what material to use for assembly. In general, if there are difficulties with self-design, then you can always just make someone else's copy.

This machine was invented for processing long parts. The abrasive belt is based on a durable cloth fabric fastened into a ring. There are different sizes. It is driven by the same electric motor with similar characteristics. But some craftsmen replace the engine with a drill. A good drill is a versatile tool in many ways. However, such a replacement is more relevant for the small size of desktop machines, as a rule, modelers use them.

How is a belt sander assembled with your own hands? The tape is stretched between two shafts or drum rollers. One of which is the master (it is attached to the motor spindle), and the second is the slave (it provides tension to the sanding belt). To prevent the tape from jumping off the drums, washers-stoppers are attached to their ends. It turns out something like a textile coil. With slight distortions, the wear of the belt occurs faster than the edges of the belt rubbing against the lock washers are destroyed. So this idea is quite viable and justifies itself.

Also, between the drums on the back side of the belt, a support screen is installed, which ensures tight pressing of the entire plane of the workpiece to the surface of the belt. To reduce the friction force, the screen is carefully polished. It can be made from both light metal and hard wood.

The drive roller must be rubberized or made of hard rubber. This will ensure that the tape does not slip on the surface of the roller. The entire structure, if necessary, can be positioned in different ways: vertically, horizontally or at an angle. To a common frame, as on all similar machines, a rigid handrest is attached, at an angle of 90 degrees, or adjustable. The distance between the tape and the edge of the hand table should not be more than 3 mm. Due to the fact that the rupture of the tape is not capable of causing significant bodily harm, protection is made only to remove grinding products.

Homemade grinder

A grinder is a high speed belt grinder or general purpose machine. Working surfaces - a disk and a tape. The engine used is the same as on all machines. And high speed is achieved by using pulleys of different diameters. A large diameter pulley is mounted on the motor spindle and is the driving one. Small pulley - tension.

On a universal machine, a disk is also attached to the spindle. You can also install an additional transfer roller, the support mounts of which will be spring-loaded. This is done to quickly change the abrasive belt.

The grinder differs from other grinders in processing speed and versatility. Using interchangeable belts for different materials, even high-alloy steel surfaces can be quickly processed.