Doing something homemade device on a belt drive, you often encounter the problem of a missing pulley required diameter. Finding it on the market or through friends takes a lot of time, and it is not yet a fact that it will be found. And not everyone has a familiar turner. In most cases, I solve this problem on my own.
What can you make a homemade pulley from?
Of course, made of plywood. If you don’t have a lathe, you have to choose from available materials. Wood is not a reliable assistant in this matter - it can easily split. But dense plywood copes with this task quite adequately.
Depending on the size of the pulley, I select plywood optimal thickness. I cut three circles out of it, two same size, and the third is slightly smaller (by the thickness of the V-belt). Also, I immediately drill a hole in each of them - strictly, in the future they will be very useful.
I clean them as much as possible, first each one separately. Moreover, on two identical circles, I chamfer one side at approximately 45 degrees. Cleaning is easier and better if you put a circle on a large nail.
I assemble the sanded plywood circles onto a bolt with a wide washer placed on the head. I try to choose the bolt itself with such a diameter that it fits snugly into drilled hole. I collect circles in the sequence large - small - large. Large ones are chamfered inward.
I smear PVA on both sides of the smaller circle, assemble the future pulley and tighten the bolt with a nut and a wide washer. And I leave the whole thing to dry well.
Although PVA glue holds the parts perfectly, for reliability they can be fastened together with self-tapping screws. Just screw them into pre-drilled thin holes.
Now the pulley just needs to be modified a little. If it is of small diameter, I insert it into a drill mounted on the table and first process it with a large file, remove the unevenness of the circle and smooth out the chamfers. And I’m finishing processing sandpaper. If the pulley is large, I put it on the electric motor and carry out the processing directly on site.
The pulley is one of the most important spare parts for both drilling and lathe machines. It is a part whose purpose is to regulate the speed and power of the engine. Of course, factory pulleys have a high degree of reliability and are designed for your machine, to which they fit perfectly.
But over time, the pulley, like many other parts, fails and requires replacement. In this article we will tell you how to make a pulley with your own hands. A high-quality hand-made part may not be inferior in reliability to factory-made analogues.
There are several views on making pulleys for machine tools at home. Most of the debate is about the material from which this part should be made. Experts say that making a pulley out of wood is a bad idea. The fact is that during operation of the machine, the pulley is subjected to quite serious thermal and physical stress. Wooden detail It won't work for very long in such conditions.
Pulleys made of metal perform best in the harsh conditions of everyday work, but their manufacture requires special equipment and high lathe skills. Average in quality and complexity of creation (compared to metal and wood) is a homemade product made from plywood. This part can be used both when repairing a factory machine and in the process of creating your own machine.
Homemade plywood pulley
A pulley for any machine can be made without the involvement of a turner. To do this, we recommend taking a plywood sheet with a thickness of about 10 millimeters and following the following instructions:
- We mark the surface of the plywood in accordance with the planned dimensions of our part. It is worth noting that these parameters must be taken into account when choosing a sheet of plywood.
- We cut circles from our material. We recommend using a jigsaw for this. During the work Special attention Pay attention to the quality of the cuts and the integrity of the workpieces.
- Considering the thickness of our plywood (1 cm), we cut out 6 circles from it.
- Take three cut circles and use a drill to drill holes in their center. Their dimensions must be compared with the diameter of the motor shaft of our machine. The holes should be drilled so that their diameter is 1-2 millimeters less than its diameter.
- We connect three circles with holes using glue and self-tapping screws, which we drill along the edges of the blanks.
- We expand the hole of the part we created using a round file to such an extent that the workpiece fits tightly onto the motor shaft.
- We also put three plywood circles without holes on glue and connect them using self-tapping screws. After these circles are securely fastened to each other, we attach them to the main shaft using longer screws.
- Six fastened plywood circles need to be turned. This is best done with a chisel or file. When performing this work, you must remember that the quality of turning will directly affect the functioning of the homemade pulley.
It is worth noting that in the same way you can make not only a drive pulley, but a flange for sandpaper and other types of attachments. In addition, during self-made pulley, it is necessary to take into account the type of belt drive that will be used on the machine. If the transmission is geared, then the pulley should also be made geared. Forming such a part will take much more time, because you will also have to make teeth on the workpiece.
Video: how to make a pulley?
Making an aluminum part
Making a metal pulley is more difficult than its plywood counterpart, but the reliability of such a part will be much higher. We provide detailed step by step instructions for the production of aluminum pulleys. To produce this part, we need a piece of aluminum and a device for melting it down.
- We prepare a mold from polystyrene foam. Before you do this, decide on the required dimensions for your pulley.
- We insert the mold into the sand so that the top piece is not covered with it.
- We smelt aluminum. It is best to do this in a special melting furnace.
- Molten aluminum is poured into the mold.
- We mount the faceplate and the smelted part. To do this, you need to drill holes in the workpiece and fasten the elements using self-tapping screws.
- We grind our detail. This can be done using a grinder.
- We make a hole in our pulley with a drill.
It should be noted that making a metal pulley requires certain skills and resources. For his self-production you will have to spend a lot more time and energy, but such expenses will pay off long term operation of such a part. Before smelting, you must also make sure that your aluminum has sufficient strength and is suitable for its intended function.
The video channel “E+M” shows the technology for manufacturing pulleys from simple and available materials using available tools. In this case, we will do without a lathe. In the second part of the publication there is another technology from another master.
Let's start manufacturing. To make type 1 you will need following materials. Superglue, sheet metal, linoleum, hot glue and a bicycle spoke.
We begin production with markings. To do this, set off the desired radius with a compass and ruler. Draw a circle on the metal. Now we set aside another radius, but one millimeter less than on the previous disks. Draw a circle on the linoleum. Drill a 2 mm hole for the axle. We apply the center of the disk and linoleum to the center of the tin. Turn it over on the other side and make holes through the stencil.
The axle is made from a bicycle spoke. To bite off, use side cutters or pliers. We assemble and connect the parts together with glue. Since you are turning, we fix it with hot glue. The photo shows an example where a similar pulley is used.
There is an engine from washing machine. Its power is enough for non-professional work. The turner lengthened the shaft and made it symmetrical on both sides. Now the task is to make a drive pulley without involving a turner. Diameter 95 millimeters. Ten plywood. Use a jigsaw to cut out 5 circles. Diameter 100 millimeters. We will connect the blanks with glue, place them on the shaft and grind them. It turned out that the thickness of the plywood is 12 millimeters, so 5 discs are enough. Total thickness 60 millimeters. Since we plan to use a standard belt for sanding machines, such a circle is sufficient for the width of the belt.
In 3 circles feather drill drill holes. The diameter of the shaft is 14 millimeters, so the drill is 12. Put it together. Apply glue and secure with self-tapping screws. After all the manipulations, the result was a pancake. Its thickness is equal to the thickness that we want to put on the shaft.
The shaft diameter is almost 2 millimeters larger. It is necessary to maintain alignment, since there are still differences inside. Insert a round file inside. Holding the file on both sides with your hands, we lay the wheel several times. How to increase inner diameter and maintain alignment.
After these procedures, we take the two remaining circles, glue them together and fasten them with self-tapping screws. In this way, you can make not only the drive shaft for the grinder, but also a flange for the emery stone. Or any other attachment for sandpaper.
The roller was mounted on the shaft. We will grind with the engine running. The centering of the shaft itself is also not one hundred percent, but this is not critical. If you want to make such a shaft, you can definitely use glue. Do not hit the pulley directly with a hammer, only through the mandrel. You can use a piece of plywood. Slowly, with light blows, he pushes on.
Pulley - important detail belt drive. It transmits the rotation of the drive shaft to the driven shaft, and also allows you to change the speed. Belt drive is common among household appliances, low and medium power machines, in various engines internal combustion. For homemade designs You can make a pulley yourself; for this you will need a home workshop and skills in working with wood, plastic, and metal.
Purchased pulleys made in factories are most often cast or machined from metal alloys. Plastic products are produced for low-power engines.
At home, without foundry equipment or precision lathes, it is difficult to make a drive wheel from these materials.
Many experts believe that a pulley made of wood, plywood or plastic, which was made in a home workshop, is unreliable, short-lived, will immediately overheat and fall apart.
It's not like that at all. If you do not try to replace the wheel of a forge hammer with a force of 6000 tons, but use it on desktop machine with limited power and speed, then a carefully made part will be able to replace the standard one for quite a long time.
You can make a pulley from sheets of plywood. This is the most simple design, she won't need it complex equipment or intricate technological processes.
If you make a part from aluminum, it will be much stronger, will be able to transmit more torque, and rotate at a higher speed. You will have to master the foundry process, even if only simple version. Manufacturing a pulley by casting will require provision fire safety, use of personal protective equipment.
The wheel can be turned on lathe, if you have one in your home workshop.
How to make a plywood pulley at home
This design is the easiest to manufacture. It consists of the following parts:
- pulley body;
- pulley cheeks;
- screw fasteners for wood.
The number of parts depends on the width of the drive belt. If it is greater than the thickness of the plywood sheet, the drive wheel body will have to be made from several plywood circles.
The diameter of the cheek piece must be greater than the diameter of the body by the height of the belt.
The sequence of manufacturing plywood pulleys is as follows:
- mark the workpieces;
- cut them out of plywood with a jigsaw, drill a central hole;
- if the body consists of two or more circles, fasten them with wood glue or PVA, making sure the axial holes coincide;
- tighten the circles with self-tapping screws;
- handle lateral surface disc with sandpaper, a file or a grinder until a smooth, even surface is obtained;
- chamfer the inner surface of the cheeks, their slope should be equal to the slope cross section belt;
- secure the cheeks to the body with glue and self-tapping screws, being careful not to get into those already screwed;
- Carefully drill out the central hole.
When performing the last operation, you need to make the diameter of the hole half a millimeter smaller than the diameter of the shaft. This will allow you to fit the detailed axle into tension. The wooden pulley is ready.
Places for self-tapping screws should be marked in advance. They must be on the same circle, as well as at equal angular distances from each other. If there are four self-tapping screws, the angle should be 90°, if there are 5 - 72°, if there are six - 60°. Then radial vibration can be minimized.
How to make an aluminum part
Manufacturing a cast aluminum pulley will be much more difficult, but the strength and durability of such a part will be much higher. You should approach each step very carefully, observe the dimensions exactly, and follow the recommendations.
A piece of aluminum will be used as a raw material. You will also need:
- melting crucible, steel or ceramic;
- muffle or induction furnace;
- fine sand, clay for molding sand;
- foam for the model.
The sequence of operations is as follows:
- prepare a molding mixture from clay, water and sand;
- cut out an exact model of the future pulley with a knife from dense foam;
- fill made from sheet metal or form boards with the mixture until half filled, compact;
- put the model down, cover it with the mixture, compact it again; leaving a hole for the release of casting gases;
- melt aluminum in a crucible and carefully pour it into the hole;
- After the casting has cooled, clean it of any remaining mixture, grind off the sprue, and sand it.
Such a part can be mounted on the shaft with a key or spline connection. It will sit much more firmly and will be able to transmit significantly greater torque and rotation speed.
Making pulleys yourself
Before repeating this or that design, you need to keep a number of points in mind. For wooden structures The diameter of the motor axis should be slightly larger than the hole.
The design must provide for camber of the internal surfaces of the cheeks with an angle equal to the slope of the cross-section of the drive V-belt. This will greatly increase the transmitted power due to the adhesion of not only the internal, but also the side part of the belt.
Before starting to manufacture the part, especially if the wheel diameter is large, a drawing or at least a sketch is a must. It will also be necessary to calculate the gear ratio - it will be equal to the ratio of the diameters of the drive and driven disks.
A homemade belt drive pulley will allow you to quickly repair the machine or create a mechanism of your own design.
It should be understood that plywood pulleys can last a long time only in structures with limited transmitted power and low angular velocities.
For cycling suspension system I needed to make several blocks. I didn’t have blanks of a suitable diameter lying around anywhere, so I turned my attention to plywood.
We cut out several approximately identical squares - in pairs for each block (but it is better to use thicker plywood).
We drill holes in the center of each of them (again, approximately) for the axle.
We glue the squares in pairs to make two blocks, which we tighten with a screw through the central holes. Tightened nuts with washers will act as a clamp, tightening the workpiece until the glue dries.
We clamp the resulting column in a vice. And grind the corners, turning the square into an octagon. I used a sander for this, but just a file or even coarse sandpaper stretched over a block will do.
We clamp the resulting part into the drill chuck and, placing it on rough sandpaper, give it the shape of a cylinder.
After this, the plywood block should be put aside for a day so that the glue sets, because... further manipulations will take place at the adhesive joint.
For further work we will need both hands, so it is advisable to firmly secure the drill to the workbench (I pulled it to the stool)). The workpiece is clamped into the chuck, the drill is turned on..
First, mark the middle of the workpiece with a pencil (to differentiate the two blocks). Then, using a round file, simply applying it to the part, we cut through the pulley groove to the required depth. The file is applied directly to the glue seam (the middle of the workpiece of one block), so you should wait for the glue to dry.
Having finished grinding the second groove, with a flat, or better yet, diamond-shaped file, we narrow the side parts of the pulleys, making them diamond-shaped - when viewed from the side - this reduces friction against the block body during rotation.
Since the blocks were not glued together in the middle, when we unscrew the screw, we will have two neat identical pulleys in our hands.