From this article you can learn how to make a cutting machine for metal do-it-yourself at home using the most simple materials. Here are detailed all the stages of creating structures, which are based on the cutting disc or grinder: preparation of materials and tools, calculation formulas, detailed step-by-step instructions, as well as accompanying information with useful tips.
DIY metal cutting machine: recommendations for creating
Disk cutting machines are tools based on the design of which there is a special platform or frame made of metal. The machine itself is equipped with parts that ensure reliable fixation of the material in a certain position at the required angle in the process of cutting.
In such constructions a disk made of high-speed steel is used as a cutting element. It is also called carbide. Can also be used for cutting metal circle coated in the form of an abrasive material. The cutting element is driven by an electric motor with a belt or gear.
Note! In low-power versions of the tool, it is allowed to use a cutting element mounted directly on the shaft of an electric motor. In other cases, such use of the disc can be dangerous.
Three different feeds of the cutting component are found on disc machines:
- lower;
- pendulum;
- frontal.
By the number of cutting elements machines are:
- single-head – only one blade is included in the device package; therefore, if it is necessary to replace the operation, the cutting edge is adjusted in accordance with the new task;
- double heads – the design makes it possible to work with two tools at once, thereby increasing efficiency. In such machines, one head is in a fixed position and is stable, the second head can move. Double head constructions can work automatically.
In the manufacture of the machine, designed to work with metal, actions are performed in the following order:
- Protective covers are being prepared that will be mounted on the drive belt as well as a cutting disc.
- The motor is installed. A drive belt acts as a connecting piece between the shaft of the cutting element and the engine.
- The shaft is made, on which the drive pulley will be fixed, and also a cutting disc is installed. The knot is subject to assembly and the subsequent installation on a pendulum. In this case, the movable upper part of the structure, where the cutting element and the motor are located, acts as a pendulum.
- Manufactured shaft for mounting the pendulum.
- Running frame for installation of the machine. It will be fixed sparkle and the workpiece.
- The pendulum is mounted on the frame.
- Electrical wiring is in progress.
- A trial run of the tool and adjustment of the equipment.
The calculation of the diameter of the pulleys is carried out taking into account the rotational speed of the disk and other parameters. If we assume that the engine power will be at least 300 W, the rotational speed of the disk will be at least 3000 rpm, and its size in diameter will be 40 cm.
Helpful advice! In the process of cutting metal nut in the area of fixation of the disk can turn away. To avoid this, it is recommended to place the drive pulleys on the left side, and the disk itself on the shaft – on the right.
Usually discs are labeled by the manufacturer, which puts on the product the maximum allowable value of rotational speed. In this case, the figure is 4400 rpm. Therefore, it is allowed to choose any speed in the range of 3000-4400 rpm.
Data for calculations:
- rotational speed of the motor – 1500 rpm;
- the diameter of the pulley intended for installation on the shaft is 6.5 cm;
- disk rotational speed – 3000 rpm
The calculation is performed in the following sequence:
- Set the length of the shaft around the perimeter. For this number?, Which is equal to 3.14 multiplied by the size of the diameter: 3.14 x 6.5 = 20.41 cm (the length of the shaft around the perimeter).
- The resulting value is multiplied by the required number of revolutions: 20.41 x 3000 rpm. = 61230 cm / min.
- The result must be divided by the number of revolutions of the engine: 61230 cm / min / 1500 rpm / min. = 40.82 cm (length of the pulley for the engine around the perimeter).
- The resulting value is divided by the number?: 40.82 cm / 3.14 = 13 cm (required pulley size).
To perform these calculations will require the following data:
- driving pulley parameters (radius);
- the distance separating the central points of the pulleys;
- driven pulley parameters (radius).
Having 2 pulleys with dimensional parameters of 13 cm and 6.5 cm, it is possible to make the necessary calculations. Since the distance between the centers of these elements is amenable to change (as it is required to bring the belt into a tension state), a length of 50 cm will be taken as an example.
Now you need to calculate 1/2 the circumference of each of the pulleys. As the drive belt passes between them twice, it is necessary to add twice the distance between the center points to this value.
First pulley (circumference):
3.14 (number?) X 3.25 cm = 10.20 cm
Second Pulley (circumference):
3.14 (number?) X 6.5 cm = 20.41 cm
Drive belt (required length):
20.41 cm + 10.20 cm + 50 cm x 2 = 13.06 cm
Helpful advice! To get a more accurate result, you should make calculations with the maximum and minimum distance between the central points of the pulleys and choose an average value.
To independently make the design of the machine for working with metal, you must prepare the necessary tools.
Mandatory tools and materials include:
- welding machine;
- metal corner (steel);
- channel and chain;
- button to turn on / off;
- bearings;
- shaft and electric motor;
- electric drill;
- sheet steel to create a work surface;
- box for placement of electrical components of the machine.
The scheme of making a homemade machine is subject to certain principles, they need to be considered before taking up the case:
- It is very important to choose the right gear and install it. The safety of torque and its correct transfer from the engine to the cutting element (disk) depends on this component;
- be sure to provide for the presence of a vice. This tool contributes to more comfortable work, and also increases the degree of its safety;
- selection of the optimum cutting angle. The allowable range is between 45-90 °. In most cases, experts prefer cutting at right angles;
- the diameter of the cutting disc is selected taking into account the materials with which the master will work on this machine in the future. The larger the diameter of the cutting element, the easier it will be to cope with the cutting of thick metal;
- when designing and drawing up drawings, such factors as the dimensions of the future machine and its weight are necessarily taken into account. These values are directly influenced by the materials from which the equipment will be manufactured. The importance of the layout of parts.
Note! In drawing up the drawings, special attention should be paid to the vibration mount, which are mounted on the legs.
After all the tools have been prepared and the drawings are selected, you can proceed directly to the process of creating the machine. Using a steel corner, it is necessary to make the frame part of the structure. In accordance with the drawings, which you can make yourself or find in the network, cut out the frame elements. All of them are interconnected by welding. First you need to check the fit of the sizes.
The channel is welded to the upper part of the frame – it will become a guiding element and will serve as the basis for further installation of the cutting component on the machine. This channel will become a kind of link between the electric motor and the cutting element. After that on it by means of bolts vertically located racks are fixed.
It will be necessary to weld the construction of another frame. Dimensional parameters are selected individually, taking into account the dimensions of the electric motor and its features. When choosing an electric motor for a machine, it is better to pay attention to modifications of the asynchronous type. This type of equipment is characterized by increased reliability and durability.
There is one subtlety when choosing a motor. The more powerful the engine, the smoother the drive will be.
Installation of equipment involves the installation and connection of the working shaft to the electric motor of the machine. The way in which this can be done is not fundamental. If the drawings contain instructions for performing this procedure, it is better to follow it, since proper operation and reliability of the tool depend on the quality of the installation.
Helpful advice! Some parts that you cannot manufacture yourself can be ordered from a turner. These include flanges for fixing, as well as a pulley.
For fixing the motor on a metal frame, it is better to use a bolted connection with nuts. Not far from the engine, it is recommended to locate the box where the switch and electrical circuit are located, as well as the control panel for controlling the instrument.
Channel, designed to fix the cutting disc, it is better to put on the spring. You need to make sure that when you release it, it will return to its original place. To fix the spring, you can take the bolts and clamp.
The electrical component is the most important part of the tool. It is mandatory to include in the design of the circuit for start-up, as well as the button for emergency shutdown of the machine. It is necessary to achieve such an arrangement of parts in which the electric motor will be connected to electricity through a machine and box, and not directly. The three-lane starting machine will be enough to turn on and fully start the engine. It will also power the off button.
Finally, it is worthwhile to take care of the presence of protective devices that will secure a person in the process. To do this, make a protective cover. It will prevent sparks and small metal particles from entering the eyes.
Designs of cutting machines made on the basis of the grinder, there are two types (depending on the location of the grinder).
In the first case, it turns out the bed, on which the angle grinder is very rigidly fixed. Above the working surface rises only a disk for which there is a special slot in the table. Such a machine operates on the principle of a circular saw.
Note! In the process of working with such a machine, you have to independently move the workpiece, because of which accuracy is lost. In addition, this process may be unsafe, so drawings with a hidden type of placement of the Bulgarians are not in high demand.
The second option assumes that the workpiece remains stationary and the cutting element moves. Due to the fact that the grinder is located on top of the tabletop, for cutting parts is not required to make serious efforts.
When making an independent tool, it should be borne in mind that the accuracy with which it will work depends largely on the stability of the structure. For this reason, the thickness of materials for manufacturing is associated not so much with the requirements regarding the strength of the machine body, as with the need to ensure an adequate level of rigidity.
List of materials:
- profiled tube with a square section (2.5 x 2.5 x 0.25 cm);
- sheet steel (sheet thickness 0.4-0.5 cm);
- profiled tube with a rectangular section (4x2x0.25 cm);
- ball bearings – 2 pcs. (No. 203, 204 or 202);
- a calibrated bar of no more than 10 cm (thickness is selected taking into account the hole on the inner bearing race);
- metal bar (diameter 0.8-1 cm);
- fasteners (bolts with nuts, thread M or M8);
- metal tire (2×0.4 cm).
List of tools:
- angle grinder;
- electric drill (can be replaced by a drilling machine);
- set of drills;
- a set of dies designed to form a metal thread;
- welding machine;
- carob keys.
Angle grinder is the main hub of the machine for working with metal. Experts do not recommend for these purposes to use a small tool that has a power of no more than 500-600 watts. In such grinders, cutting discs have a diameter of no more than 12.5 cm. These limitations are due to the fact that a cutting element with a large diameter is considered universal and very reliable – it is able to cope with cutting thick workpieces.
Helpful advice! Instead of welding for fixing parts, you can use threaded connections, but they are less reliable and will not be able to provide the necessary level of strength.
Careful approach to the choice of grinders is also necessary because there is a wide variety of designs on the market. Since this power tool is not fully unified, the construction of the machine will be carried out under a certain modification and dimensions of an angle grinder.
If the machine breaks down, installing another grinder may not only be problematic, but also impossible. We’ll have to redo the pendulum and all the fixtures. Therefore it is worth choosing a tool from the range of large and already proven companies, for example, Bosch or Makita.
At the preparatory stage, the design and drafting of drawings. Uniform size does not exist for the reason that the design of each machine is subject to a particular model of the cutting tool. Finished drawings, which are many in the network, can be customized to fit the grinder. They allow you to navigate in terms of what will be the structure of the structure, its dimensions.
Drawing drawing is better to start with the body. In some cases, it may be necessary to build a separate platform instead of a frame. Such a platform will be fixed on the metal workbench. Next, determine the size and nature of the location of the node elements on the machine. It is necessary to measure the center distance between the mounting holes located on the gearbox, as well as measure the grinder itself.
All these data are used to compile the drawings. After the mounts for the pendulum and the grinder are designed, a swivel unit is designed.
Helpful advice! The accuracy and rigidity of the machine depends on the distance between the cutting element and the hinge. The smaller this gap, the better. It is recommended to install the pendulum with a minimum length.
After drawing up the drawings, it will only be necessary to select materials, calculate their quantity and proceed to the construction.
The manufacturing technology of the machine for cutting metal on the basis of the grinder is almost the same as in the case of the cutting disc:
- Preparation and manufacture of parts for the frame.
- Arrangement of swivel on the pendulum lever.
- The manufacture of a U-shaped bracket with holes for mounting the grinder reducer.
- Making a U-shaped clamp and strips that will fix the body of the grinder on the pendulum.
- Installation of U-clamp and U-shaped bracket to the cutting tool: by welding or threaded connections, all these parts are mounted on the cantilever part.
- Pressing bearings in support.
- Double-sided pressing of bearing units on the shaft. To increase the strength of the joint, it is possible to tin the axis with a thin layer of tin with a soldering iron.
- The fastening of the pendulum with the supporting nodal parts on the edge of the platform (indent from the edge of 0.5-0.6 cm) using a welding machine.
- Installation of grinders and protective cover.
- Assembly of the return spring.
After the construction is assembled, it is necessary to perform a test run and verify the correct operation of the equipment, as well as the placement of all parts on it. At the final stage, the groove is adjusted to the cutting element, and supports are installed to secure the workpieces.
When finishing is completed, the machine body must be covered with a thin layer of enamel. Coloring will protect the tool from damage that rust may cause.
