Grinder (grinding machine): belt and disk, diagrams, manufacturing, components. Homemade grinder with an engine from an automatic washing machine Homemade grinder with an engine from a washing machine


Washing machines often fail without their motors being fully functional. Its power and actual speed are well suited for the use of this spare part in the manufacture of homemade machines. As it turns out, such an electric drive is also perfect solution for installation on a homemade grinder.

Materials used

It didn't take much to make:
  • motor from a typewriter;
  • its original starting capacitor;
  • part of the sheet metal covering of the machine;
  • 4 rubber feet from the washing machine;
  • plywood sheet;
  • a 5 cm piece of thick-walled tube with an internal diameter of 14 mm;
  • 2 identical bearings;
  • glass sealant;
  • sheet metal with a cross section of 8 mm;
  • corner 63x63 mm;
  • profile pipe 40x40 mm;
  • profile pipe 30x30 mm;
  • extended nut;
  • steel strip with a cross section of 10 mm;
  • furniture gas shock absorber;
  • power button;
  • plastic plugs 30x30 and 40x40 mm;
  • bolts and nuts M12, M10, M6 and M5.
The main detail of the entire structure:


The process of making a grinder from a washing machine motor

First I made tension rollers.


These are factory metal ones. Ours will be homemade, wooden. Moisture-resistant plywood is suitable for their manufacture; its thickness is not so important.


You need to make pancakes out of it, which will then be glued together into a roller. First, I install a wood bit with a diameter of 102 mm on the drill. I cut out 9 plywood pancakes for the drive roller. The number of circles depends on the thickness of the existing plywood and the width of the tape that will then be used.


Now the pancakes need to be glued together. First you will have to sand them a little to remove chips from the crown. I grease the side of the circles with PVA glue and form a wide multi-layer roller. For normal gluing, I fix the workpiece under a press.


While the drive roller is drying, you can make a driven roller. It uses a 64 mm crown. Again, using a drill, I cut out 9 pancakes from the same plywood and glue under pressure.


To prevent the rollers from delaminating after they dried, I made 2 side holes in them and additionally tightened everything with a pair of screws on each side.
I balance the rollers in lathe, slightly grinding down the irregularities and achieving smoothness of the workpieces.


To secure the drive roller to the motor shaft, you need to make an adapter. For this, a piece of thick-walled tube is used.


In most cases, a pipe with an internal diameter of 14 mm will be required. To tighten the tube on the electric motor shaft, I drill a hole and cut an M5 thread. At the second end of the tube I weld an M12 bolt.



I expanded the drive roller hole to fit the tube by half the depth. The remaining narrow part will contain the thread from the M12 bolt.
You need to install a pair of bearings in the driven roller, one on each side. Their size is not so important; you can use any, as long as it has a suitable internal diameter. I prepare the bearing housings on a lathe.




To make the surface of the rollers smoother, I decided to coat them with glass glue. To do this, I fix them one by one in a lathe and coat them evenly around the perimeter and ends.




Now you need to make a frame for installing the electric motor. I use it as a base a metal sheet cross section 8 mm. I cut out a rectangle with sides 220 by 310 mm.


To directly mount the engine you will need 2 corners. I am preparing pieces 130 mm long. The 63rd corner was ideal for the electric motor.


I lay the steel plate on a flat surface, install the angle and the motor, then make markings for drilling the mounting holes with a 6 mm drill.


To prevent the corner from interfering with the drive roller fixing bolt in the future, you need to select metal close to the shaft. The easiest way is to cut out a small triangle.



I mount the angles on the electric motor using four M6 nuts with a press washer.


I install the motor with the mounts in place, make markings and weld the corners to the base of the machine.


I cut off from profile pipe 40x40 blank 300 mm long. I make another piece of the same length, but from a 30x30 mm profile pipe.


Now you need to make a mechanism for adjusting the tape. To begin with, I take an elongated nut and grind its edge.


I weld it to a steel strip with a cross section of 10 mm. I drill a hole on the strip and cut an M10 thread for the bolt on which the driven roller will be fixed.


Then I welded an L-shaped blank from a previously cut 30x30 square pipe. I welded nuts to it to secure the strip made. I also secured the nut and bolt on the perpendicular wall of the square opposite the head of the bolt on which the driven roller will be mounted. By tightening or unscrewing a short bolt, you can change the angle of the roller, thereby adjusting the machine.



I place a 40x40 profile pipe vertically on the machine platform and weld it. At the same time, I try on the place so that the driven roller stands opposite the driving one, which in turn is fixed to the motor shaft.


To ensure smooth tension of the tape, you need to install a gas furniture shock absorber between a 40x40 vertical pipe and a 30x30 L-shaped roller holder.




I make a support platform for the machine from available materials. Using a small piece of profile pipe 40x40 and a 63rd angle. I made a cutout on the pipe to increase the welding area. I attached the corner with bolts, since it will need to be removed for maintenance. I made all the blanks without preliminary dimensions, simply adjusting them to the location.



And now I’m preparing a table for resting the workpieces being turned. For this I use the same sheet metal with a cross section of 8 mm. I made the width of the table 80 mm.
I'm preparing the base for the table. To do this, I take a 40x40 pipe with a length of 120 mm. I drill a hole in it, sharpen the end in a semicircle and cut an M10 thread. I make small ears out of sheet metal. They will act as loops. I weld the ears to the tabletop.

Grinder (English) literally – crusher. Meat grinder is a meat grinder, rock (stone) grinder is a stone crusher; stick (wood) grinder – garden crusher of branches and twigs into chips. But there is also a completely unambiguous meaning of the word grinder: in mechanical engineering and metalworking it is grinding machine. A useful household item. For example, it is impossible to guide a dull meat grinder knife on a whetstone manually. On a manual knife sharpener - somehow possible, having solid working skills. And on the grinder - no problem. The same applies if you need to polish a part of a complex shape without disturbing its profile. Or just sharpen scissors or a professional knife. Various kinds Wood and metal cutters are best edited on a grinder. 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 of 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 external turning at all. For example, how to make a simple grinder literally out of trash, see the video below:

Video: DIY belt grinder made from trash

Or another option, how to make a stronger and more durable grinder from scrap metal:

Video: scrap metal grinder

Disc or tape? And drive

There are almost more types of grinding machines used in industry than lathes. The emery known to all craftsmen - a motor with a pair of grinding wheels (or one wheel) - is also a grinder. For yourself at home, it makes sense to make either a disk end grinder (plate grinder) or a belt grinder. In the first, the abrasive is applied to a rotating hard disk; in the second - on an elastic band running around a system of pulleys and rollers. Disc is more suitable for grinding simple wooden parts and coarse or medium purity - metal. Using a belt grinder, it is also possible to produce precise and clean finishing of profiled parts of complex shapes, incl. large-sized, see below.

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

A worn-out “plate” is suitable: a disk made of thin (4-6 mm) fibrous plastic is glued to 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 disk and tape grinder is not only in the possibilities of use. If we take ordinary household crafts, then for a disk grinder a drive power of 250-300 W on the shaft is enough. For small wooden parts - and 150-170 W. This is the motor from the old one washing machine, straight (regular) drill or screwdriver. But for a belt grinder you will need an engine from 450-500 W: three-phase with batteries of starting and operating capacitors. If you plan to process large items, then the motor power is from 1-1.2 kW. Moreover, capacitor batteries for both will cost not much less than the engine itself.

Note: a 100-200 W drive uses a mini-belt grinder (see below) for precise knife dressing, 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 movement of the abrasive (see below) using a standard speed controller. You just need, firstly, to make a holder for the drill that rigidly fixes the tool. Secondly, an elastic transition coupling from the drill to the disk shank, because It is difficult to achieve their precise alignment without special equipment, and runout will negate the accuracy of processing and can damage the drive tool.

Drawings of a drill holder for using it as a home drive metal cutting machine are given on the left in the figure:

Since shock and irregular alternating loads on the drive in a grinder are an order of magnitude lower than, say, in a lathe, a 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. It is highly advisable to use a drill without impact mechanism and with a steel shell on the neck (for installing the front handle).

coupling

For the adapter coupling, you will need a piece of steel rod (not necessarily turned) of the same diameter as the shank of the grinder drive shaft, and a piece of PVC-reinforced hose (garden irrigation) with a clearance such that it stretches tightly over the rod 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 reliable clamping in the drill chuck. After assembling the coupling in place, the hose on the shank and rod is tightened tightly with clamps; can be wired. Such a coupling completely counteracts the misalignment of the drive and driven shaft up to 1-1.5 mm.

Tape is still better

A belt grinder allows you to do everything a disk grinder can do, and much more. Therefore, next we will focus on how to make a belt sanding machine with your own hands. Amateurs, focusing on industrial designs, sometimes make very intricate grinders, see figure:

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

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

Kinematics and design

As mentioned above, there are many designs of grinders. When considering what and how to build a grinder for yourself, it is better to focus on industrial designs designed to be fully mechanized for precise and clean grinding of large-sized profiled parts: once it “sands” the blade of an airplane propeller or wind turbine properly, it can handle any other work.

Kinematic diagrams of grinders for the specified purpose are shown in Fig.:

Basic kinematic diagrams of belt grinding machines (grinders)

Pos. A is the most complex and perfect, with three rocker arms. If the length of the tension roller rocker arm is approx. 2 times less than the working one, then by adjusting the tension of the springs, it is possible to achieve 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 belts of different lengths. Secondly, in the same way you can quickly change the belt tension for different operations. The working branch of the belt 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.

The scheme with a coaxially swinging rocker arm (item 2) is simpler, cheaper and in terms of processing accuracy is not inferior to the previous one, if the length of the rocker arm between the axes is at least 3 diameters of the workpiece. To reduce the profile by grinding, the stroke of the rocker arm is limited by stops within 10 degrees up and down. The pressure of the belt to the part is most often gravitational, under the weight of a rocker arm with a bypass pulley. The tension of the belt can be quickly changed within certain limits by pulling the rocker up with a weak adjustable spring, partly compensating for its heaviness. The grinder of this design can work as a grinder for small parts from a sliding table. In this case, the rocker arm is rigidly fixed horizontally, and the working surface of the belt will run around the bypass pulley. For example, the fairly popular BTS50 grinder is made using a coaxial rocker design. The disadvantages of the scheme are, firstly, the technologically complex rocker arm joint, which is coaxial with the drive shaft. Secondly, the need for an elastic band: if you make the idler pulley sliding and spring-loaded, the processing accuracy decreases. This drawback when processing small parts is completely eliminated by an additional tension roller, see below.

The scheme with one misaligned rocker arm is used quite rarely in industry, because in principle, it does not allow achieving uniform tape tension. However, it gives 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 circuit from the point of view of an amateur master. And then we’ll try to figure out how to make a grinder belt ourselves and do without custom-made turned parts.

3 rocker arms

Competent amateurs build their grinders exactly according to the scheme with 3 rocker arms, on the left in Fig. below. Not all propeller blades can be ground, but in this case another advantage of this scheme applies: if the grinder is used as a vertical grinder, then the working branch of the belt is elastic. This allows to a skilled craftsman, for example, aim cutting edges and blades with literally micron precision.

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

The dimensions are, however, inch - the machine is American. For the drive, in any case, it is possible to use an angle drill-grinder (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 an asynchronous motor at 2-3 speeds from an unusable washing machine with a horizontal tank. Its advantage is low speed. This makes it possible to make a drive pulley large diameter and thereby prevent the tape from slipping. A belt slip during operation is almost certainly a damaged part. Most washing machines with 2-3 speed asynchronous motors for 220 V are Spanish. Shaft power – 600-1000 W. If you come across one, don't forget about the standard phase-shifting capacitor bank.

Coaxial rocker

Amateurs do not make pure grinders with a coaxial rocker arm. A coaxial hinge is a complicated thing; you can’t make an elastic band yourself, and store-bought ones are expensive. Grinders with a coaxial rocker are most often used at home in the version for small precision work from a table, i.e. with a rigidly fixed horizontal rocker arm. But then the need for a rocker arm as such disappears.

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

Its features are, firstly, an overhead bed for the tape (item 7), which significantly expands the possibilities of use. For example, the plane iron is straightened on this grinder with an angular stop literally by itself. In this case, the grinder works, so to speak, like a self-propelled whetstone (emery block). Having removed the bed, we get a grinder with an elastic band for precise grinding/polishing of rounded small parts. Secondly, the tension shaft (item 12). By clamping it to the groove with nuts, we get a relatively fixed tension of the tape for working with the bed. And after releasing the nuts, we switch the grinder to the gravitational belt tension mode for fine work. Drive - not necessarily through a pulley (pos. 11). You can screw it directly onto the drive shaft shank (item 16) from the drill through the adapter coupling, see above.

A specialized tool grinder (for example, for guiding and straightening turning tools) generally loses any semblance of the original design. A high-speed motor is used for it (200-300 W is enough power). The drive pulley is, accordingly, of small diameter. The bypass pulley, on the contrary, is made larger and heavier for inertia. All this together helps reduce tape runout. The tension roller for the same purpose, plus for greater uniformity of belt tension, is moved further away and spring-loaded with a long, not very strong spring. How to make a grinder for processing incisors, see the video below.

Video: grinder for making cutters


One rocker

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

In this case, the original scheme is also modified: the rocker arm is rotated 90 degrees, moved upward and spring-loaded, on the left in Fig. It turns out to be a simple vertical grinder. And, importantly, it works without problems with homemade non-stretchable tape. A tension spring (in the center) or a compression spring can provide tension to the tape. Its strength is not so important, as long as the tape does not bend excessively during operation. No adjustments are required during use.

Consumables and parts

The only one consumables for a belt grinder - tape (not counting lubricant for bearings and hinges. The tape can be ordered to the desired length (see at the end), but you can also make it yourself from sandpaper on textile based. It is highly desirable - flexible, unimpregnated. In general, the procedure for making a grinder belt with your own hands is as follows:

  • We cut the workpiece - a strip of the required 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 outline the mandrel with the workpiece inside out.
  • We bring the ends of the workpiece exactly end to end and securely fasten them.
  • Place a piece of glue stick for a hot glue gun on the joint.
  • Gray construction hairdryer until the glue melts.
  • We apply a patch of thin fabric to the joint.
  • Press with 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 for the patch. It is very durable, but just try running your finger across a PET bottle. Not very slippery? Rough PET film cannot be stretched under tension even over polished metal. And instead of a patch, it is better to seal the back of the tape with a continuous strip of PET film with an overlap of 2-3 cm. The runout 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 blank skin.

Second, insert the finished tape into the machine and grind something indecent with it without strong pressure. The scar on the seam will be sealed, and the tape will become no worse than the branded one.

But the most important thing is elasticity best glue for gluing the grinder tape, it is not expensive and difficult to use thermo- or mounting, but ordinary PVA. If the tape is covered with a lining along the entire length of the back, then its PVA strength will be more than enough. How to glue PVA grinder tape, see video

Video: gluing grinder tape with PVA glue

Pulley

Formative ( side surface cross-section) of the grinder drive pulley should be straight. If you use a barrel pulley, the belt will bend like a trough along its entire length. The rollers prevent it from slipping, see below, but the generatrix of the pulley must be straight.

A pulley for a grinder that is not intended for particularly precise work, firstly, does not have to be turned. In a scheme with 3 rocker arms, the beating of the belt from its misalignment will go out on the rollers before it reaches the working branch. In a simple vertical grinder, the beating of the belt 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

Secondly, the pulley, rollers and, in general, all the parts of a home grinder can be made from plywood. In production, this is certainly not an option, even if a 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 it and itself. But you won’t be running a grinder at home every day in 3 shifts. And no tape slips along the plywood pulley. Incl. homemade. So you can safely make a grinder pulley from plywood:

Video: pulley for grinder made of plywood


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

Fortunately, for most abrasive-material pairs, the permissible belt speed limits are quite wide, so choosing a pulley for the grinder can be easier:

Video: what wheel is needed for a belt grinder

Rollers

The rollers of the grinder, oddly enough at first glance, are its most important parts. 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 grinder for incisors. Only barrel rollers can cope with this task, see below. But the “trough” of the belt after any roller must straighten before it reaches the working area.

Rollers with flanges (sides, edges) will not hold the tape. The issue here is not only and not so much with the misalignment of the roller axes: the grinder belt, unlike the drive belt, must withstand the loads from the parts being processed without slipping. If you make videos with flanges, then if you barely touch the tape with something, it will creep 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 for turned steel and not less than 35-40 mm for plywood. The tension roller (the probability of the tape slipping from it is greatest), if the working branch of the tape does not come off it, can have a diameter of 0.7-1.2 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 processed cleanly, see e.g. track. video:

Video: barrel roller for grinder


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

And another option

All critical parts of the grinder - a solid belt, pulleys with a coating that prevents it from slipping, rollers - can be purchased separately. They won’t be that cheap, but still not thousands of foreign ones and not dozens of native leather jackets. The remaining parts of the grinder, either flat or from corrugated pipes, are made using a regular tabletop drill or drill. Here's where you can order parts for the grinder:

  • //www.cora.ru/products.asp?id=4091 – tape. Lengths and widths are made according to the customer's wishes. Consult on abrasives and processing modes. Prices are reasonable. Delivery time - questions to Ruposhta.
  • //www.equipment.rilkom.ru/01kmpt.htm – spare parts (components) for grinding machines. There is everything, the prices are divine. Delivery - see previous page.
  • //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 ones suitable for grinding.
  • //dyplex.by.ru/bader.html, //www.syndic.ru/index.php?option=com_content&task=view&id=36&Itemid=36 – spare parts for grinders. They do not make ribbons to order - choose from the catalogue. Rollers without axles; axles sold separately. The quality is impeccable, but everything is very expensive. Dispatch - within 2 weeks to the border. Then - their customs, our customs, Rusposhta. Total approx. 2 months It may not arrive if some local bureaucrat considers the product sanctioned. In this case, there are no problems with the return of payment due to the complete absence of real opportunities for the average citizen to receive one.
    • (2 ratings, average: 5,00 out of 5)

If you have an unwanted washing machine that you couldn't sell, you can put it to good use. You can make a homemade grinding machine from a washing machine motor. This device is called a grinder.

It has advantages over grinding machines– allows you to conveniently process the ends of products, as well as small parts. Find out how to assemble the machine yourself in our article.

When to use the machine

Grinder is used for final processing parts from roughness - before painting or varnishing. Also for leveling defects and imperfections on surfaces.

The machine will allow you to get the job done quickly and efficiently. In addition, it comes with tapes of various grain sizes, so the scope of application is quite wide. Depending on the choice of tape, you will be able to process products from:

  • wood;
  • become;
  • non-ferrous metal.

Using a homemade engine from washing machine It will be convenient to grind parts various forms what won't you do hand tools. For example, triangular, pipe, flat and round objects.

Preparatory work

You will need to make a moving element with your own hands along which the tape will move. If you buy it separately to assemble the structure, it will cost about the same amount as a new machine.

What parts are needed for the job:

  • corners: one 40 cm long and two 15 and 25 cm long;
  • 2 long bolts and several regular ones, nuts, washers, spring;
  • hairpin;
  • a piece of metal measuring 30x100 mm.

What tools will you need:

  • lathe;
  • drill;
  • welding machine;
  • pliers;
  • open-end wrenches;
  • Bulgarian.

You also need parts that can only be made on a machine or ordered in a workshop. This:

  • roller;
  • bearing;
  • sleeve;
  • screw;

How to assemble a grinder from a washing machine motor: instructions

Now take the prepared corners. Using welding, connect the corners, as seen in the photo below. Parallel weld two small metal plates with holes for the bolt to the bottom.

A bolt with a spring attached to it, installed in the end hole of the structure made of corners, will help you adjust the tension of the tape on the machine. Make a hole in the top of the angle for a short bolt. Screw the short part of the corner into this place, which is not fully secured with a bolt. The short part should move, allowing you to change the tension of the tape.

Then install the roller with the bearing mechanism. Do not tighten the roller on the corner too much; it should rotate freely. Secure one end of the roller with a nut and weld the other welding machine to the corner.

Install the stud. To do this, make an additional hole in the corner under the roller. After threading the pin, secure it with two nuts on one side. When installing the stud, make sure that it fits into the thread.


As you can see in the photo above, there is one more element in the design. This is a corner with a piece of chipboard, which is secured with short bolts. It is needed for your safety. The belt is tensioned using a pin, so your hands will be close to the fast moving belt. This bar will protect your hands from damage.

How to connect the motor

All that remains is to connect the electric motor. It is advisable to use an asynchronous motor from an automatic washing machine. The power can be from 200 to 300 Watts, and the speed can be from 1500 to 3000 per minute. Therefore, the performance of the belt will depend on the characteristics of the motor.

It's good if the engine has a long enough shaft. But if this is not the case, then you need to increase it yourself. Here you will need a special wood bushing made on a machine. The bushing is put on the motor shaft, after which the tape is put on it.

To ensure that the tape does not move during operation, but is located in the middle, you need to make central part the bushings are 2-3 mm larger.

Installing the tape

You can buy special tape or make one from sandpaper. Its width should be no more than 200 mm. Cut the fabric into strips of appropriate length. Now the strips need to be connected. Use only special glue. Then proceed like this:

  • When laying the pieces end to end, apply glue to them.
  • Place a piece of fabric on top and press firmly.
  • Then cover with a sheet of paper and secure with a hot iron.
  • Trim excess material around the edges.

Since there will be a strong impact on the tape, the connections must be made efficiently.

When putting the tape on the grinder, make sure that the overlapping seam does not ride up during operation.

How to Adjust a Grinder

The tape is adjusted using a pin that is installed in the structure homemade machine. By twisting and unscrewing the pin, you influence the degree of pressure (tension) of the tape.

Here you need to be careful: if you work at high speed with little tension, the processing may be of poor quality, with missing areas. If you reduce the speed and tighten the tape more, you can damage the product.

Also select the grit size of the abrasive according to the material being processed.

Having understood the details of the work, you will acquire useful technology for home use.

Do-it-yourself grinder. Homemade grinder with a washing machine motor. After 2.5 months of lack of free time, time began to appear. I decided that I wouldn’t do anything with a knife until I made a small grinder. Otherwise I won’t get it together again. I started by selecting the adjusting roller. At work, the feed roller from a dot matrix printer had been lying around idle for a long time.

Upon closer examination, it turned out to be excellent material.

External diameter 45 mm. Inner diameter 30 mm. The thickness of the rubber coating is 3 mm. The thickness of the duralumin tube is 4 mm.

I cut off a 40 mm piece, gave it to a turner, who machined the spaces for the 32 mm bearings and, at the same time, lightly machined the barrel.

A crown for drilling holes for sockets. Diameter 80 mm. Cost 45 Nr. Plus Victory drill in the broth. Easy tuning from a turner led to this result.

Tape 533 x 75 mm, cut lengthwise/in half. Fitting

A piece of tile also went into use.

Result

When I did it I was afraid that the engine power would be insufficient. Nothing like that. It gnaws metal (quick cutter, file) like a beast. Satisfied. But I have already started to improve it. I want to make it possible to use 610 mm tapes. I hope to finish it next week. Of course I'll show you.

Hi all. I bring to your attention a homemade grinder with an engine from an automatic washing machine.

The motor is commutator, power 400W. Speeds are adjustable to process different materials. A homemade block made on Arduino was used as a regulator.

Let's get started. An iron sheet 7 mm thick was taken for the base. The plate size was 250 by 300 mm. Cut from the same piece vertical stand and weld it as in the picture. Also, don’t forget about the scarf to add rigidity. There are no special dimensions here, since everything was done for a specific engine. You also focus on what you have. But I think you’ll understand the general layout. A drive roller with a diameter of 55 mm was also ordered. It is installed on the motor shaft and secured with an M6 bolt.






The upper knot serves to adjust and hold the belt in working position. It consists of two plates twisted perpendicularly to each other. a roller is attached to one with a bolt, and a nut with a screwed-in adjusting bolt is welded to the other.



When the bolt is screwed in, the plate with the roller bends in one direction, and when unscrewed in the other. This is how the tape is adjusted against displacement. Well, the rollers themselves must be in the same plane. Also, the top roller is made in the shape of a barrel. This allows you to keep the tape in one position while working. This unit is attached to the vertical post with a bolt. Between the plates there is a thrust bearing from the front strut of a Ford car. This connection should be movable, but without play. It serves to tension the tape. WITH reverse side spring is tensioned.

Now I made a bracket for the pressure pad from a channel cut in half. It has grooves for adjustment. The pressure pad itself is welded to the second piece. It is screwed to the first trim on a bolted connection to be able to adjust the position of the platform.








The work table is cut from 10mm sheet. Size about 150 by 300mm. A bracket with a hole is welded to the warp and a gusset is added. The same plate is welded to the table. The hole is made in the form of a slot. This allows the table to be adjusted. It can be moved closer or further relative to the tape, as well as change the angle of inclination. This is convenient when sharpening various instruments. During the assembly process, the table is positioned perpendicular to the side of the tape.




The entire structure was disassembled and painted for a more aesthetic appearance.


What can be said about the engine, its power is quite enough. The speed on the regulator is set to 6000. With this diameter of the drive roller and speed, the belt speed is decent, and together with the adjustment they can process various materials. The engine must be closed to prevent metal dust from entering.

This is the assistant machine that appeared in my