Do-it-yourself stationary circular saw - according to our drawings and instructions, anyone can do it. Setting up a circular saw - step-by-step instructions with photos Connecting the emergency stop button for a circular saw

The household often lacks a circular saw, especially if major renovations or construction are underway. Not everyone can afford industrial products - they are too expensive. But you can make a circular saw yourself, using materials that are available in the household.

Design - main components, their purpose

A do-it-yourself stationary circular saw is created with advancement in several possible directions:

adapting existing hand tools using the motor and circular saw for new capabilities;
improvement of industrial products to expand functionality;
assembly of individual parts, manufactured mainly in-house.

A stationary circular machine includes several main components: a table, a shaft, a motor and some others, the characteristics of which are not so important.

The table is used for fastening woodworking mechanisms. It can be assembled entirely from metal, which is preferable, especially for machines with a high-power engine. Wood also makes good circular tables. But it is necessary to take into account that the tabletop should be covered with a sheet of metal, otherwise the wood will soon wear out. Tables must be very rigid and stable, capable of withstanding considerable load during work. The surface is made perfectly flat; protective shields must be installed above the rotating parts.

For a homemade circular machine, a washing machine motor is quite suitable. Portable tools are less suitable: their commutator motors are designed only for short-term work. They have very high speeds, low efficiency, and are afraid of clogging. You can use a three-phase electric motor, but if the household does not have 380 V, you will need to purchase capacitors to make it work on 220 V.

The most critical component is the shaft. Use a ready-made one, if available, or machine it from round metal. The work on the lathe is performed in one setup, then the assembly with the working parts is checked for centering. Even minimal runout is unacceptable, otherwise during work it will become stronger, at which it is unacceptable to work. Seats are provided on the shaft: for a circular saw and for pulleys on the other side. You can also make grooves for planing knives.

Main parameters - calculation of power, speed, gear

The characteristics of the circular saw, the engine and the maximum thickness of lumber that can be cut are interconnected. The maximum speed for which it is designed is indicated on the purchased circular disk. The number of revolutions transmitted by the engine to the shaft should be less. The engine power affects the maximum permissible saw tooth diameter. The diameter must be at least three times the thickness of the material, otherwise sawing will be difficult. It is believed that to cut materials 100 mm thick, you need a motor of at least 1 kW of power.

The transmission is made only by a V-belt - if foreign objects get under the saw, the material jams, the belt slips on the pulleys. Injuries in such cases are practically eliminated. It is important to choose the right gear ratio. We take into account two indicators: engine speed and the maximum permissible speed of the circular saw. We calculate the required pulley diameters. A pulley with a large diameter is installed on the engine, and a smaller one on the circular shaft to increase the number of revolutions.

The revolutions of the shaft with a circular saw are as many times greater than the engine revolutions as the diameter of its pulley is smaller than the diameter of the pulley on the engine.

Woodworking machine - a capital product for the home

To work with wood in large volumes, it is better to have a machine that allows you to cut the material, plan it, and select a quarter. A fairly powerful electric motor and a rigid table are required. We present a structure made of steel angle and sheet steel. It provides a cutting depth of 60 mm; you can plan boards 200 mm wide. A three-phase motor of 1.1 kW, 2700 rpm is used. To connect to 220 V, capacitors are required.

1 – machine frame; 2 – panel; 3 – starter; 4 – device for height adjustment; 5.7 – work table of two halves; 6 – base; 8 – engine; 9 – platform; 10 – M10 studs; 11 – circular disk; 12 – shaft; 13 – stops of the lifting mechanism; 14 – driven pulley; 15 – belt; 16 – drive pulley; 17 – switch.

The work table has dimensions of 700×300 mm. In the drawing we see that the height of the entire structure is 350 mm. The height is not sufficient for comfortable work; the circular saw will have to be installed on an additional platform; it weighs only 35 kg. You can increase the length and width, increase the height up to 1200 mm. We adjust the remaining sizes to fit them, but the design features remain unchanged.

First we make the bed frame from steel corners 25x25 mm. If we are not going to increase the height, we make another similar lower frame. For a frame with a higher height, first we weld four legs from the same corners to the upper frame, and then we tie them at a height of 15–20 cm from the bottom. The lower frame has grooves for the engine platform locking bolts. Two studs are welded to the back side of the platform, which go into holes on the back of the lower frame. By tightening the studs, we tighten the belts, then we lock the platform by tightening the nuts on the studs that go into the grooves.

To adjust the height of the table in relation to the saw, we use a simple lifting mechanism. It consists of racks, in the upper part of which we cut grooves at an angle of 45°. A total of eight racks are needed - four on each side. We weld them to the frame with grooves located in a mirror image. We attach cross members to the outer posts. We drill holes in the middle of each of them and weld nuts. Threaded shafts will move along them to regulate the lift.

Their ends rest against racks welded to frames assembled from 75x50 mm corners. We weld studs into them on the side opposite the grooves for the adjustment mechanism. The table consists of two equal halves and is attached to the frames with countersunk bolts. The adjustment mechanism works like this:

loosen the nuts on the racks;
we turn the screw, which presses on the stop, raising or lowering the table;
tighten the stud nuts;
We perform a similar adjustment for the second half of the working surface.

The design can be simplified without installing an adjusting shaft. Raise and lower the table manually. If you assemble the table not from two halves, but from one piece, you will only need four racks for the lifting mechanism.

Hand-held circular saw - turning into a stationary one

It’s easy to make a stationary one from a hand-held circular saw, expanding its capabilities. The first thing you need is a table. A convenient material is Finnish plywood, which, unlike ordinary plywood, is laminated - the workpieces glide well over the surface during processing. It is thick enough to withstand a lot of weight, moisture resistant, and easy to process. You can use ordinary 20 mm plywood, but you just need to paint it, or better yet, cover it with sheet steel or textolite.

You need to understand that the depth of cut will decrease by the thickness of the cover. You will need a large diameter disk so as not to reduce functionality compared to a portable tool. We make the dimensions of the tabletop sufficient to ensure that the workpiece fits in width. It should be added that on a wide table you can additionally strengthen an electric plane and a jigsaw, which will make the machine universal.

Using drawings and explanations, it is not difficult to make additional accessories for a circular saw that will expand its capabilities.

We mark a rectangle of the required dimensions on a sheet of plywood, cut it out, and process the edges. Using the sole, we apply a hand-held circular saw to the surface and mark the attachment points with a pencil. We make a slot for the circular saw. You can slightly deepen the attachment point using a milling cutter, but not more than 10 mm, so as not to weaken the tabletop. This manufacturing method will allow you to bring the cutting depth closer to that indicated in the circular saw’s passport.

From the boards we make a frame (tsars), which we install from below to strengthen the structure. We fasten four boards into a box, glue them to the tabletop, securing them with clamps. We screw self-tapping screws into the boards across the table. We countersink the holes for them from above so that the heads of the screws are hidden. We attach the legs to the frames of the stationary saw, preferably with bolts, washers and nuts. The table should be provided with additional rigidity, so we make spacers at the bottom of the legs.

We make a limit bar equal to the length of the working surface. In it we drill two grooves perpendicular to the disk, in which the bar will move and be fixed at a certain distance from the saw blade. It remains to make changes to the control system: we fix the control button in the on state with electrical tape. We install an outlet connected to the network on the drawer. We install a switch in the gap in the wire going to the saw.

Some aspects of the execution of homemade devices

No matter how well a circular machine is made, individual errors can lead to its performance being limited. This concerns, at first glance, seemingly trifles. Let's start with the bearings for the shaft. Installing conventional ones is justified if the machine is used from time to time. For a homemade device with permanent use, it is better to install self-aligning bearings. They consist of two rows of balls and are adjusted by tightening the clamping nut. Be sure to install a cover to protect against dust and chips.

On the working surface we apply a scale in centimeter increments. This will make woodworking much easier when determining the width of the cut. Many people neglect to install a protective shield over the disk, but in vain - treatment for chips getting into the eye or in more serious situations is more expensive.

When working with various materials, it is often necessary to adjust the speed of the circular saw. A homemade design, as a rule, does not have the ability to regulate engine speed. There is only one way out - the use of pulleys of different diameters. They are installed on the motor shaft. If you decide to order pulleys from a turner, immediately make a solid pulley with two or three different diameters.

Many people want to install a three-phase electric motor on a sawing machine, without having 380 V. They will need capacitors designed for a minimum operating voltage of 600 V of paper or oil-paper type.

We calculate the capacitance of the capacitors based on the power of the electric motor: for 1 kW - 100 µF for the working capacitor Av. We take the capacity of the starting joint twice as large. The SB trigger is a button that automatically returns to its original position. Startup is simple: turn on SQ, press SB for a couple of seconds. After starting, the button is released, as soon as the engine picks up speed, you can cut.

The working motor from an automatic washing machine should not gather dust in the garage. Even a home craftsman can find a use for it. We will tell you how to make a homemade circular from a washing machine engine.

This tool will help you cut wood and master carpentry. However, be careful: careless use of a homemade machine can lead to unpleasant consequences. Therefore, before taking on a job, you must be completely confident in your abilities.

The choice of engine for creating a mini-circular depends on its power. It is advisable to use an engine with a V-belt, which will allow its speed to be transmitted to the saw blade of the machine.

A 350 mm disk will require 1 kW of energy to start. A disk with a diameter of 170 mm will require about 500 W. Therefore, you can install a motor from an old washing machine.

It is important to regulate the number of engine revolutions, otherwise instability in operation will lead to the disc tearing the material.

In the washing machine, the speed is controlled by a tachometer, which is controlled by a control module. But it is impossible to connect a module to the circular, so install a voltage regulator. Use the wiring diagram to correctly install the motor.

DIY circular machine with washing machine motor

You have figured out which motor is needed and how to connect it. Now consider the design diagram of a circular saw.

For a circular saw made at home, the absence of a bearing assembly is allowed, which will significantly simplify the design.

The main load will be on the moving elements. This:

saw and electric motor shaft;
motor pulley and saw shaft;
drive belt.

Let's look at the features of each of them:

The drive belt does not have to be taken from the washing machine; other belts can be used. The main thing is that they have serrations, like a V-belt.
Flow grooves need to be made on the small pulley. The belt will cling to them during operation, which will prevent slipping.
A larger disc is welded onto the large pulley, which will prevent the belt from slipping off.
To fasten the circular saw, use a shaft into which it is mounted, as well as a washer and nut, which are used to secure it. It is recommended to select or take this kit from the factory to ensure the drive is secured as securely as possible.

When creating a design, you need to take into account that it is designed for a three-hundredth disk. Of course, a self-made circular machine is only suitable for household use. Therefore, try not to overload the engine.

Preparing the electrical part

A starter can be installed to start the saw. If you provide thermal protection for overcurrent, then if jammed, the switch will turn off automatically. A button from a door lock will do.

Often such machines are stored in the yard, on the street, so protect the electrical part from moisture.

Manufacturing of frame and bed

The frame is made of metal sheet 3 mm thick. Before making the frame, prepare a 30 mm metal corner.

As shown in the photo above, the craftsman installed the frame into homemade pipe racks. Now it is possible to adjust the height of the device. However, it is recommended to make a solid frame by welding pieces of corner together. Strong vibration over time loosens the fastenings of bolts and other elements.

When making a circular saw, consider the possibility of repairing it. All moving parts should be easily lubricated. Before starting work, it is advisable to prepare detailed drawings.

Please note that the mini circular saw varies in size. It is much smaller than usual and can fit into a pantry when stored.

How the device works

The engine starts, which drives the shaft and pulley. As a result, the drive belt rotates, transmitting speed to the circular saw pulley. The saw begins to rotate, allowing the material to be cut.

A homemade circular saw is always useful in the household. Due to the fact that it can be made from improvised materials, it will cost you almost free.

A circular hand saw is a fairly practical tool with which you can quickly cut a piece of wood of any length and width along or across, or cut any wood-based sheet material. In addition, after changing the equipment, you can use a circular saw to cut plastic, metal corrugated sheets and corrugated sheets. Despite the simplicity of the design and high reliability of this unit, it is susceptible to breakdowns, like any power tool. But in most cases, you can repair a circular saw yourself at home.

A hand-held circular saw differs from a miter saw in the absence of a frame with a rotary table, as well as the placement of the handle. But in general, both models are similar in internal structure, operating principle and do not differ in design complexity. The following figure shows the structure of a hand-held circular saw.

The unit consists of the following main elements.

Upper protective casing with an opening for sawdust ejection.
The housing that houses the electric motor and the start button. Some models of electric saws can be powered by rechargeable batteries. In this case, the battery pack is also placed on the case.
Lower (movable) protective casing, which automatically closes the cutting element after it leaves the workpiece.
Saw blade. It is attached to the gearbox shaft using a nut or bolt.
Parallel stop. Allows you to make an even cut without the use of additional devices.
Base plate (sole) of the unit. Thanks to it, the tool is installed on the workpiece or tire at different angles.
Depth regulator. With its help, you can adjust the reach of the saw blade relative to the base plate.
Adjustable sole angle. Allows you to tilt the sawing unit at an angle.

This tool works according to the following principle. Power from the mains or battery is supplied to the start button, which breaks the circuit. When you press the start button, current begins to flow to the electric motor. Below is electrical diagram of the unit.

The electric motor starts and transmits rotational motion through the gearbox to saw blade The unit is installed using a sole on a workpiece or guide bar, after which the process of both longitudinal and transverse sawing is carried out.

Main malfunctions and their symptoms

Typical malfunctions of manual circular saws include the following situations.

The saw does not turn on. The power cord, power plug, start button or power brushes may be faulty.
The tool motor gets very hot. Such symptoms may be the result of an interturn short circuit (break) in the armature or stator coils, as well as too intense operation of the unit.
The gearbox of the device overheats. Overheating of this unit may occur due to bearing failure or lack of lubrication on the gears.
The brushes spark. This usually occurs due to excessive wear and tear.
A burning ring is visible around the engine manifold.. If during operation of the unit there is a circular spark around the engine commutator, then its appearance may be caused by a malfunction of the armature winding or clogging of the space between the commutator lamellas with graphite dust.
The unit does not develop the required power. A drop in power may be due to a drop in voltage in the network, a malfunction of the motor windings, wear of the electric brushes, or a malfunction of the start button.
A grinding noise is heard while the unit is operating. and other extraneous sounds. These symptoms can be caused by broken gear teeth or faulty bearings.
The engine hums, but the unit does not work. The gearbox may have jammed.

Disassembling the tool

Almost all problems with electric circular saws cannot be eliminated without disassembling the device partially or completely. Complete disassembly of a hand-held electric saw using the Interskol unit as an example is performed in the following order.

Unscrew the angle and depth adjustment screws attached to the base of the device.
Press the gear shaft lock button and use a hex wrench to unscrew the bolt holding the saw blade.
Move the lower protective cover to the side and remove the circular disc.
To remove the support sole, first unscrew the fasteners on its underside.
Next, you need to use two screwdrivers to remove the Sieger ring, which locks the rod on which the sole rotates, to change the angle.
Insert a screwdriver into the gap between the shield body and the sole, then move it aside and remove it.
In the next step, unscrew all the mounting screws located on the upper casing of the unit.
Also unscrew the screws holding the movable saw guard.
Remove both safety guards from the saw.
Using an open-end wrench, unscrew the bolt holding the riving knife and remove it.
Unscrew the rod holding the movable mechanism of the casing and disconnect all its elements.
Next, you should disconnect the unit gearbox by unscrewing 2 screws.
When the mechanical part of the device is disassembled, you can proceed to disassembling the electrical part devices. Unscrew the fasteners holding the engine cover and remove it.
When you remove the cover, you will see two electric brushes. If they need to be completely disconnected from the engine, it is recommended to use a marker to mark one of them, as well as the place from which it was removed.
Next, you should unscrew the screws that secure the motor housing to the gearbox housing.
After unscrewing the fasteners, disconnect both units.
In the disconnected part of the motor housing you will see stator coil.
Next, you should unscrew all the fasteners from the handle of the unit. But before disconnecting it, you need to remove the rubber pad by prying it off with a screwdriver.
By removing one half of the handle, you will see engine soft start module and start button.

This completes the complete disassembly of the circular saw.

DIY circular saw repair

When starting to repair a unit with your own hands, it is not necessary to completely disassemble it to find out the causes of the breakdown. Some malfunctions have specific symptoms, by which you can identify the problem and purposefully disassemble this or that part of the device.

The saw does not turn on

If the unit’s engine is “silent” when you press the start button, then the first thing you should focus on is network cable, provided that there is electricity in the outlet (to check, connect the device to another outlet).

Advice! Before checking the cable, you need to disassemble the electrical plug and make sure that the cord conductors are securely connected to its pins.

To check the electrical cable, you need to disconnect the handle. This will help you get to the contacts to which the power cord wires are soldered. Next, use a tester to test each wire, pressing one probe to the soldered contact, and the second to the pin of the plug.

If the network cable is intact, then do the following to find the problem.

Use a tester to test the entire circuit, starting from the cable entry into the unit to the start button. You should also check the button contacts at its input and output when the key is pressed. In normal condition, an open circuit should close. Call everyone wires after the button, going to the motor brushes.
If everything is in order with the conductors, check how The brush electrodes are worn out. Once the electrode is worn to 2/3 of its original size, it should be replaced. The brushes, regardless of how worn each one is, are replaced in pairs.
If the brushes are in good condition, then most likely engine failed. A break or interturn short circuit could occur in its windings. In this case, it is better to entrust engine repair to specialists who will rewind the stator or armature coils.

The engine is getting hot

The unit may become excessively hot, for example when its intensive use, as well as when sawing hardwood or using a saw blade with a large number of teeth, when the load on the engine increases significantly. Also causing motor overheating are faults associated with the stator and armature windings, which can only be repaired at a service center.

The brushes are burning

Strong sparking from under the brushes is caused by their excessive wear when the spring can no longer press the electrodes to the collector with the required force. To replace the brushes, you need to disconnect the motor cover or remove them through special holes in the motor housing (depending on the model of the electric saw).

Shaft jammed during operation

This problem can occur when the stopper is pressed for any reason while the tool is running. It is designed to secure the shaft when replacing accessories and should be used after the engine has completely stopped. Otherwise, the stopper rod breaks and debris falls into the engine, causing it to jam. There are often cases when this leads to armature shaft deformation. Also, pressing the stopper may result in a split of the gearbox housing, fragments of which can damage the gears and cause them to jam. To solve the problem, you will need to replace the armature, stopper, drive (large) gear of the gearbox and its housing.

In some cases, the gearbox may jam if the bearing is completely destroyed.

The saw stops during operation

Engine stopping in most cases is caused by cavity worn out electric brushes. When the contact between the brush electrode and the commutator lamellas is broken, the unit turns off.

Often, when purchasing brushes for this device, you come across products with short conductor connecting the electrode to the plate. This conductor is located inside the spring and prevents it from fully expanding. When the electrode wears down to a certain length, its pressing against the collector stops, since this is prevented by a short conductor. If, upon examining the brush, you find that it is not yet worn out and the spring does not decompress, then the part should be replaced.

The gear housing gets very hot

Rapid heating of the gearbox occurs if The shaft bearing has become unusable, on which the gear is fixed and the equipment is attached. In this case, in addition to heating, you can replace the appearance of extraneous noise in this unit of the device. It is necessary to disassemble the gearbox and change the bearing. Also, the gearbox will heat up if there is not enough lubrication or it is completely absent.

Advice! Periodically, the gearbox should be disassembled and checked for lubrication. If necessary, generously fill the internal space of the unit with lubricant. For these purposes, you can use a special lubricant for grinder gearboxes.

The saw does not gain power

If while using the unit you notice a drop in its power, it is first recommended check the voltage level in the network. Sometimes even a slight drop can negatively affect the power of the power tool.

Also, a loss of power can be observed when wear of armature bearings or gearbox bearings. In this case, extraneous noise will be heard that was not previously characteristic of this unit. By their location, you can determine where the problem bearing is located - in the gearbox or engine. To replace the bearings, you will need to disassemble the circular saw. How to do this was described above.

If you don’t hear any extraneous noise during operation of the unit, and the engine still has poor speed and power, then pay attention to its manifold. Usually you can see a circular spark (ring of fire) on it. This may occur due to the interturn short circuit of the armature coil or the accumulation of dirt between the commutator lamellas.

Open the motor housing and carefully inspect the commutator (the area where the brush electrodes slide). It consists of parallel strips (lamellas). There is a small gap between them. When this gap gets clogged conductive graphite dust, formed when the brushes wear out, a short circuit occurs between the lamellas, and a burning ring appears around them.

The problem can be solved by replacing worn brushes and cleaning the gaps between the slats using a toothbrush, cotton wool and alcohol, followed by polishing the plates with fine sandpaper.

In some cases, a loss of power can be caused by a faulty start button. If testing by a tester confirms its malfunction, then the part should be replaced with a new one, since it cannot be repaired.

Extraneous sounds appeared during operation

The appearance of grinding noise and other extraneous sounds can be caused by faulty bearings or gears of the gearbox and shaft with worn or broken teeth. In the following picture, the arrow shows where the armature gear is located.

The gear located on the motor shaft may become licked when the saw jams in hard or loose wood. Usually the gearbox gear is not affected. To eliminate this breakdown, you will have to completely change the engine armature. If the bearings break, they can be easily removed using a puller and replaced with new ones.