Do-it-yourself laser cutting of cardboard. DIY laser cutter

Any CNC laser machine does an excellent job, for example, with the manufacture of gift souvenirs, furniture, engraving on various materials and creation of advertising products. Using a laser unit, you can forget about manual cutting. Burning on any surface passes without problems.

Making a CNC laser machine with your own hands is not difficult, it's like assembling a designer from components, below we'll talk about how it's done and what components we need.

The device of the laser CNC machine

The first devices of this class had one common and very significant drawback - their high price. Now laser machines are much cheaper and even small enterprises are able to get them into use. The simplest equipment of this class costs about 50,000 rubles.

But if we will talk about a full-fledged machine, its price will increase at least 4 times. Due to the fact that the machines became affordable, attention to them began to grow rapidly. The first thing that interests people who encounter such machines is how they work.

Exactly the same as in milling machines, homemade laser analogues are controlled by the CNC module. Therefore, they are assembled from such basic parts:

1. Frame.
2. Horizontal platform (desktop).
3. A place for tools (there is a working module - a laser).

For precise movement in the space of the laser head, a stepper motor is used. It works according to the given program.

The laser itself consists of the following parts:

• laser tube;
• the head of the radiating part;
• reflectors (ordinary mirrors);
• lenses for beam focusing.

During the operation of the laser CNC machine, a special solution based on nitrogen and carbon dioxide enters the tube, and helium is also added. A current is supplied through this mixture (working substance) high voltage, resulting in a laser beam.

Before reaching the work surface, the beam is directed through mirrors and focused to a point using lenses. The head of the emitter is shifted to the right place with the help of stepper motors and, according to the program, draws a given pattern. To cool the laser, or rather, its tube, a liquid system is used, consisting of a pump and a water circuit.

Principle of operation

Before you start assembling such a unit at home, it is important to understand how it works. There are three main conditions that allow the laser to work normally. If at least one of them is not observed, the beam of the required intensity simply will not arise. Here are the conditions:

1. Source of power.
2. Working environment.
3. Optical resonator.

The energy source fills the working medium with photons of a certain charge.

These photons pick up particles that are similar to them from the active medium. When moving in a liquid, photons begin to accelerate due to collision with the atoms of the working medium, which leads to an increase in the potential of the installation.

At the other end of the tube is installed frosted glass through which the photon beam exits. The beam is formed in such a way that all its photons meet at one small point, superimposing their energy on each other, as a result, the processed material is fired.

Video: do-it-yourself laser CNC machine.

Do it yourself

In order to make such an apparatus alone, you need to understand the device of the machine. Let's take a closer look at what the machine consists of:

• The main part of the device is its body. It is best to make it collapsible. In the event of a setup or breakdown, access to the mechanism will be easier. It would be nice to equip the frame with drawers for tools, blanks and finished products.
• Lift tables. It is necessary to make a table so that it can be adjusted in height. Roofing sheets with rising and falling platforms can be engraved. You can make a mechanism for raising the table with a handle or put servos that will do everything for you using the buttons.
• Rotor. This is the part that will rotate the cylindrical workpiece for its full processing. If you plan to work with round products, the rotor will have to be installed anyway.
• Guides. They need to be made of metal or plastic and give a round or square section. The first parts are easier to make, and they can handle any task from engraving to cutting. In addition, the speed of round guides (working speed) is higher than that of square guides. Guides wear out over time, so be prepared to purchase and install new parts over time.
• Working surface. For machines that will work with wood, it would be advisable to install special lamella legs. If you are installing another type of workpiece, or bigger size, such knives are easy to remove and put away. If your future machine will process small parts, install a grate that will prevent them from falling into the mechanism. This grate needs to be cleaned from time to time in order to avoid its complete clogging.
• Compressor and extractor. These parts are needed for the selection of soot and chips obtained during the operation of a laser machine for cutting plywood. The more powerful the suction effect, the better the processing will go. In addition to small fragments of the workpiece, these units remove the smoke that is formed during the firing of the workpiece.
• Pointer. This is an indicator (you can use a portable laser) that indicates to the service personnel which place will be processed next. When it comes to CNC machines, such a pointer is not necessary at all.
• Electronic components of a do-it-yourself plywood cutting machine. It is important to choose the right equipment to ensure signal transmission to the stepper motor and laser. As a control element, you can choose one of the Arduino programmable boards. These kits are relatively inexpensive and can be used to assemble any control mechanism. There are a lot of materials on the programming and installation of such systems on the network; if you have minimal skills in working with a soldering iron, installing Arduino will not cause you any difficulties.

You also need to take care of the software that you will use to create an electronic drawing of the future part. The software is needed to transfer the workpiece in digital form from a PC to the homemade machine itself.

It's no secret that each of us in childhood wanted to have such a device as a laser machine that could cut metal seals and burn through walls. AT modern world this dream is easily becoming a reality, since it is now possible to build a laser with the ability to cut various materials.

Of course, at home it is impossible to make such a powerful laser machine that will cut through iron or wood. But with the help homemade device Can cut paper, PE seal or thin plastic.

With a laser device, you can burn various patterns on sheets of plywood or on wood. It can be used as a backlight for objects located in remote areas. Its scope can be both entertaining and useful in construction and installation work not to mention the realization of creative potential in the field of engraving on wood or plexiglass.

cutting laser

Tools and accessories that will be required in order to make a laser with your own hands:

Figure 1. Diagram of a laser LED.

• faulty DVD-RW drive with a working laser diode;
• laser pointer or portable collimator;
• soldering iron and small wires;
• 1 ohm resistor (2 pcs.);
• capacitors for 0.1 uF and 100 uF;
• AAA batteries (3 pcs.);
• small tools such as a screwdriver, knife and file.

These materials will be quite enough for the upcoming work.

So, for a laser device, first of all, it is necessary to select a DVD-RW drive with a mechanical breakdown, since the optical diodes must be in good condition. If you do not have a worn drive, you will have to purchase it from people who sell it for parts.

When buying, keep in mind that most of the drives from the manufacturer Samsung are unsuitable for the manufacture of a cutting laser. The fact is that this company produces DVD drives with diodes that are not protected from external influences. The absence of a special housing means that the laser diode is subject to thermal stress and contamination. It can be damaged with a light touch of the hand.

Figure 2. Laser from a DVD-RW drive.

The best option for a laser is a drive from the manufacturer LG. Each model is equipped with a crystal with a different degree of power. This figure is determined by the burning speed of dual-layer DVDs. It is extremely important that the drive is a recording drive, since it contains an infrared emitter, which is needed to make a laser. The usual one will not work, since it is intended only for reading information.

The 16X DVD-RW is equipped with a 180-200mW red crystal. A 20X speed drive contains a 250-270mW diode. High-speed recorders of the 22X type are equipped with laser optics with a power of up to 300 mW.

Back to index

Disassembling a DVD-RW Drive

This process must be done with great care, because the internal parts are fragile and easily damaged. Having dismantled the case, you will immediately notice the necessary detail, it looks like a small piece of glass located inside the movable carriage. Its base must be removed, it is shown in Fig. 1. This element contains an optical lens and two diodes.

At this stage, it should immediately be warned that the laser beam is extremely dangerous for human vision.

With a direct hit on the lens, it damages the nerve endings and a person can remain blind.

The laser beam has a blinding property even at a distance of 100 m, so it is important to be careful where you point it. Remember that you are responsible for the health of others while such a device is in your hands!

Figure 3. LM-317 chip.

Before starting work, you need to know that the laser diode can be damaged not only by careless handling, but also by voltage drops. This can happen in a matter of seconds, which is why diodes work based on permanent source electricity. When the voltage rises, the LED in the device exceeds its brightness norm, as a result of which the resonator is destroyed. Thus, the diode loses its ability to heat up, it becomes an ordinary flashlight.

The crystal is also affected by the temperature around it, when it falls, the laser performance increases at a constant voltage. If it exceeds the standard norm, the resonator is destroyed according to a similar principle. Less commonly, the diode is damaged by sudden changes, which are caused by frequent switching on and off of the device within a short period.

After removing the crystal, it is necessary to immediately bandage its ends with bare wires. This is necessary to create a connection between its voltage outputs. To these outputs you need to solder a small capacitor of 0.1 uF with negative polarity and 100 uF with positive polarity. After this procedure, you can remove the wound wires. This will help protect the laser diode from transients and static electricity.

Back to index

Food

Before creating a battery for the diode, it must be taken into account that it must be powered from 3V and consumes up to 200-400 mA, depending on the speed of the recording device. Connecting the crystal directly to the batteries should be avoided as this is not a simple lamp. It can deteriorate even under the influence of ordinary batteries. The laser diode is an independent element, which is powered by electricity through a regulating resistor.

The power system can be adjusted in three ways with varying degrees of complexity. Each of them involves recharge from a constant voltage source (batteries).

The first method involves the regulation of electricity with a resistor. The internal resistance of the device is measured by detecting the voltage during the passage through the diode. For drives with a write speed of 16X, 200 mA will be sufficient. With an increase in this indicator, there is a possibility of spoiling the crystal, so you should stick to the maximum value of 300 mA. As a power source, it is recommended to use a telephone battery or AAA type batteries.

The advantages of this power scheme are simplicity and reliability. Among the shortcomings, one can note the discomfort with regular recharging of the battery from the phone and the difficulty of placing batteries in the device. In addition, it is difficult to determine the right moment to recharge the power supply.

Figure 4. LM-2621 chip.

If you use three AA batteries, this circuit can be easily equipped in a Chinese-made laser pointer. Finished construction shown in Figure 2, two 1 ohm resistors in series and two capacitors.

For the second method, the LM-317 chip is used. This way of arranging the power supply system is much more complicated than the previous one; it is more suitable for a stationary type of laser systems. The scheme is based on the manufacture of a special driver, which is a small board. It is designed to limit the electric current and create the necessary power.

The circuit for connecting the LM-317 chip is shown in Fig. 3. It will require elements such as a 100 ohm variable resistor, 2 10 ohm resistors, a 1H4001 series diode and a 100 microfarad capacitor.

The driver based on this circuit maintains electrical power (7V) regardless of the power source and ambient temperature. Despite the complexity of the device, this circuit is considered the easiest to assemble at home.

The third method is the most portable, making it the preferred method of all. It provides power from two AAA batteries, maintaining a constant level of voltage applied to the laser diode. The system retains power even when the batteries are low.

When the battery is completely discharged, the circuit will cease to function, and a small voltage will pass through the diode, which will be characterized by a weak glow of the laser beam. This type of power supply is the most economical, with an efficiency of 90%.

To implement such a power system, you will need an LM-2621 chip, which is housed in a 3 × 3 mm package. Therefore, you may encounter certain difficulties during the soldering of parts. The final size of the board depends on your skills and dexterity, since the details can be placed even on a 2 × 2 cm board. The finished board is shown in Fig. 4.

The inductor can be taken from a conventional power supply for desktop computer. A wire with a cross section of 0.5 mm is wound on it with a number of turns up to 15 turns, as shown in the figure. The throttle diameter from the inside will be 2.5 mm.

Any Schottky diode with a value of 3 A is suitable for the board. For example, 1N5821, SB360, SR360 and MBRS340T3. The power supplied to the diode is adjusted by the resistor. During the tuning process, it is recommended to connect it with a 100 ohm variable resistor. When checking the performance, it is best to use a worn or unnecessary laser diode. The current power indicator remains the same as in the previous diagram.

Having chosen the most suitable method, you can upgrade it if you have the necessary skills for this. The laser diode must be placed on a miniature heatsink so that it does not overheat when the voltage rises. Upon completion of the assembly of the power system, you need to take care of installing optical glass.

All photos from the article

Is it difficult to assemble a plywood laser cutting machine with your own hands? What problems can be expected at different stages of project implementation? What equipment will you need to buy? In the article we will try to find answers to these questions.

Pros and cons of laser cutting

When implementing any large-scale project there is always a question of its expediency. We will try to help the reader to give an independent answer to it.

Benefits

• The device for laser cutting plywood in practice is able to work not only with it. The list of processed materials includes leather, fabrics, plexiglass, plastics, in a word, all materials that have low thermal conductivity and a relatively low combustion temperature;
• Thanks to the CNC, the machine will allow you to cut with the highest precision, creating detailed contours;
• Its possibilities are not limited to sharp. Laser cutting machines for plywood are quite capable of performing the functions of an engraver. By varying the speed of the carriage and the power of the beam, they can create complex images with tone transitions;
• By focusing the beam, the width of the cut can be kept to a minimum- from 1/100 mm, which again has a positive effect on the accuracy of manufacturing parts or the detail of the image applied to the workpiece.

Problems

Of course, without them, too, will not do:

• The price of the purchased equipment will not be cheap. The most popular solution for inexpensive home-made engravers - a laser diode extracted from a DVD burner - is categorically not suitable for cutting plywood due to low power. The minimum laser power for cutting plywood is 20 watts; with any significant thickness of the material, it is better to increase it to 40 - 80;

Reference: CO2 laser tube of this power when ordered directly from Chinese manufacturers will cost the customer 15 - 20 thousand rubles at the current rate. The cost of a complex and expensive focusing system, DSP controller, stepper motor driver and carriages will be added to the cost of the laser.

• The life cycle of the tube is from 3 to 8 thousand hours, after which it needs to be replaced;
• The laser requires liquid cooling. In industrial conditions, for this purpose, cooling plant working on the principle heat pump- chiller. The minimum cost of such a unit is 35 - 45 thousand rubles;

However: with a short duration of work, you can get by with a tank with a capacity of 80 - 100 liters and a water pump that will pump its contents through the tube jacket.

• CNC implies the presence of not only special software, but also sketches of the contour of the manufactured product. Drawings for laser cutting plywood are not so easy to find; their independent construction will take a very long time;
• Finally, the cutting of the material is carried out due to its rapid heating and evaporation. In this case, the edges of the cut are inevitably charred, and the room is filled with smoke. If so, you will have to design a closed case with a transparent lid and an intensive forced ventilation system.

Design

So how is it arranged homemade laser for cutting plywood?

The base of the bed is an aluminum profiled pipe 40x60 in size, fastened furniture corner and self-tapping screws for metal. The case is assembled from inexpensive laminated chipboard - it does not experience significant loads during operation.

Please note: a 12-volt LED Strip Light. The backlight will allow you to visually control the cutting process.

Guides are fixed directly on the tubes of the frame, ensuring the movement of the carriages along the transverse axis.

A longitudinal pipe with another guide is screwed to the carriages - already under the carriage, which provides direct movement of the head.

And here is the laser head itself for cutting plywood. The foil is used to seal the connection of the tube with the fitting.

The possibility of making something useful from unused or worn-out equipment attracts many home craftsmen. One such useful device is the laser cutter. Having at your disposal a similar apparatus (some even make it from an ordinary laser pointer), you can perform decoration products from various materials.

What materials and mechanisms will be required

To make a simple DIY laser cutter, you will need the following materials and technical devices:

• laser pointer;
• an ordinary flashlight equipped with rechargeable batteries;
• an old writable drive (CD / DVD-RW) equipped with a laser drive (it is not at all necessary that such a drive be in working condition);
• soldering iron;
• set of locksmith tools.

In this way, a simple laser cutting device can be made using materials that are easy to find in a home workshop or garage.

The manufacturing process of a simple laser cutter

The main working element of a home-made cutter of the proposed design is the laser element of a computer disk drive. It is necessary to choose a writing drive model because the laser in such devices has a higher power, which allows you to burn tracks on the surface of the disk installed in them. The design of the reader-type disk drive also contains a laser emitter, but its power, used only to illuminate the disk, is low.

The laser emitter, which is equipped with a writing drive, is placed on a special carriage that can move in two directions. To remove the emitter from the carriage, it is necessary to free it from a large number fasteners and detachable devices. They should be removed very carefully so as not to damage the laser element. In addition to the usual tools, to remove the red laser diode (and to equip the homemade laser cutter, you need it), you will need a soldering iron to carefully release the diode from the existing solder joints. Removing the emitter from seat, care must be taken not to subject it to strong mechanical stress, which can cause it to fail.

The emitter removed from the writing computer disk drive must be installed instead of the LED, which was originally equipped with a laser pointer. To perform this procedure, the laser pointer must be disassembled by dividing its body into two parts. At the top of them is an LED, which should be removed and replaced with a laser emitter from a writing computer drive. When fixing such an emitter in the body of the pointer, you can use glue (it is only important to ensure that the eye of the emitter is located exactly in the center of the hole intended for the beam to exit).

The voltage generated by the power sources in a laser pointer is not enough to ensure the efficiency of using a laser cutter, so it is not advisable to use them to equip such a device. For a simple laser cutter, rechargeable batteries used in a conventional electric flashlight are suitable. Thus, aligning the lower part of the flashlight, which houses its batteries, with top laser pointer, where there is already an emitter from a writing computer drive, you can get a fully functional laser cutter. When performing such a combination, it is very important to observe the polarity batteries, which will feed the emitter with electricity.

Before assembling a homemade hand-held laser cutter of the proposed design, it is necessary to remove the glass installed in it from the tip of the pointer, which will prevent the passage of the laser beam. In addition, it is necessary to once again check the correct connection of the emitter with the batteries, as well as how accurately its eye is located in relation to the exit hole of the pointer tip. After all structural elements are securely interconnected, you can start using the cutter.

Of course, with such a low-power laser, it will not be possible to cut a metal sheet, it is not suitable for woodworking either, but it is suitable for solving simple tasks related to cutting cardboard or thin polymer sheets.

According to the algorithm described above, it is possible to manufacture a more powerful laser cutter, somewhat improving the proposed design. In particular, such a device must be additionally equipped with such elements as:

• capacitors, the capacitance of which is 100 pF and 100 mF;
• resistors with parameters 2–5 ohms;
• collimator - a device that is used to collect light rays passing through it into a narrow beam;
• LED flashlight with steel body.

Capacitors and resistors in the design of such a laser cutter are necessary in order to create a driver through which power supply will come from the batteries to the laser emitter. If you do not use the driver and put the current on the emitter directly, the latter may immediately fail. Despite the higher power, such a laser machine for cutting plywood, thick plastic, and even more so metal, will not work either.

How to make a more powerful machine

Home craftsmen are often interested in more powerful laser machines that you can make yourself. It is quite possible to make a laser for cutting plywood with your own hands and even a laser cutter for metal, but for this you need to acquire the appropriate components. At the same time, it is better to immediately make your own laser machine, which will have decent functionality and work in automatic mode, controlled by an external computer.

Depending on whether you are interested in your own hands or you need an apparatus for working on wood and other materials, you should correctly select the main element of such equipment - a laser emitter, the power of which can be different. Naturally, do-it-yourself laser cutting of plywood is performed by a device of lower power, and a laser for cutting metal must be equipped with an emitter with a power of at least 60 watts.

To make a full-fledged laser machine, including for cutting metal with your own hands, you will need the following expendable materials and accessories:

1. a controller that will be responsible for communication between an external computer and the electronic components of the device itself, thereby providing control over its operation;
2. electronic board equipped with an information display;
3. laser (its power is selected depending on the materials for the processing of which the manufactured cutter will be used);
4. stepper motors that will be responsible for moving the desktop of the device in two directions (stepper motors from unused printers or DVD players can be used as such motors);
5. cooling device for the emitter;
6. a DC-DC regulator that will control the amount of voltage supplied to the emitter electronic board;
7. transistors and electronic boards for controlling the cutter stepping motors;
8. Limit switches;
9. pulleys for installing toothed belts and the belts themselves;
10. housing, the size of which allows you to place in it all the elements of the assembled structure;
11. ball bearings of various diameters;
12. bolts, nuts, screws, couplers and collars;
13. wooden planks, from which the working frame of the cutter will be made;
14. metal rods with a diameter of 10 mm, which will be used as guide elements;
15. a computer and a USB cable with which it will connect to the cutter controller;
16. set of locksmith tools.

If you plan to use a laser machine for do-it-yourself metal work, then its design must be reinforced to withstand the weight of the metal sheet being processed.

The presence of a computer and a controller in the design of such a device makes it possible to use it not only as a laser cutter, but also as an engraving machine. With the help of this equipment, the operation of which is controlled by a special computer program, it is possible to high precision and detailing to apply the most complex patterns and inscriptions on the surface of the workpiece. The corresponding program can be found freely available on the Internet.

By its design, a laser machine that you can make yourself is a shuttle-type device. Its movable and guiding elements are responsible for moving the working head along the X and Y axes. The Z-axis is taken to be the depth to which the workpiece is cut. For the movement of the working head of the laser cutter of the presented design, as mentioned above, stepper motors are responsible, which are fixed on the fixed parts of the device frame and connected to the moving elements using toothed belts.

Sliding support Head with laser and heatsink Carriage assembly

Placement of the carriage on the racks

Let's do this: a laser cutter for metal is like Men's Watch. Cool and unique tool essential modern man having own garage and able to do something with their own hands.

This tool can be made by hand. This is easy if you do necessary rules and instructions. The power of a homemade laser knife will not come out God knows what, but if necessary, it can be increased in several ways.

Of course, you will not have a tool for industrial needs, but for domestic household work, yours is fine.

Firstly, you can get by with improvised materials, that is, you do not have to buy anything special in the store. The most important thing is to find an old laser pointer.

Additionally, you will need:

• screwdrivers of different calibers;
• a matrix with a laser drive from a used DVD-ROM;
• a flashlight powered by rechargeable batteries;
• soldering iron.

With great care and maximum care, we disassemble the laser pointer and the drive. First you need to get the drive from the computer drive.

Important nuance: this drive must be not only a reader, but also a writer. All drives of modern computers have such properties, so before disassembling, check the model and characteristics of the drive.

Laser cutter for metal.

The second step is to find and pull out the red diode, which is used to record on the disc in the form of burning. This diode is removed simply: you need to solder the fasteners with a soldering iron.

Carry out all actions with tenderness and caution: diodes and other trifles associated with them are fragile things and ready to deteriorate at the slightest opportunity. It's easy to reduce the risk of breakage. To do this, it is enough to change the diode to a red light bulb from the DVD wire.

Now we begin to make the body of the cutter from the stored flashlight and rechargeable batteries that will be needed. Using a flashlight will allow you to produce a compact and comfortable model for work.

Don't forget to remove it protective glass, as it can become an obstacle to the laser beam in the future.

The most important moment in the manufacture of the case - right choice current polarity.

Now you need to power the diode by connecting it to the battery charger.

As a final step and before starting work, we check:

• whether the fixation in the clamps and clamps is strong;
• device polarity;
• direction and focus of the beam.

What can your cutter do?

Do not forget that your new homemade is not capable of cutting thick metal - it is simply beyond its power. But you can beef up the tool to work with almost any metal if needed.

Drawing plasma cutting metal.

Beforehand, you will need to stock up on a capacitor, because a knife with enhanced power can in no case be connected directly to the network. Therefore, first the current must go to the capacitors and only then to the batteries.

You can increase the power with the help of additional resistors. Your knife will receive additional power from the use of the so-called collimator, which serves to concentrate and accumulate the laser beam.

Collimators are very inexpensive and are sold in any department of electrical equipment.

In the case of an increase in power, at the same time, unnecessary static increases. It is easily eliminated by winding aluminum wire around the diode.

Now we need measurements: we measure the current strength at the ends of the cutter after they are connected to the diode. The indicators are adjustable, the most suitable range is from 300 to 500 mA.

Why bother?

The gadget is cool and necessary. But dear. But it’s easy to make a metal cutter with your own hands even for beginners. So the motivation to start implementing our advice is obvious.

Let's better understand the principles of the laser knife, it will be useful to everyone: those who bought it and those who made it with their own hands.

The main character is a focused laser beam, which, due to its directionality and radiation, acts, for example, on metal. The beam itself is extremely narrow - its diameter is very small. Thanks to this, cuts on workpieces are characterized by the highest accuracy.

The depth of cut depends only on the power of the tool. Here, of course, professional factory models with high deepening rates win. As for our homemade laser knife, the depth here is available at the level of 10 - 30 mm.

Scheme of the gas cutter.

Metal cutters are divided into three types:

Solid cutters

They are made of special glass or crystalline LEDs. These are relatively cheap models, produced and used in industry.

Fiber laser knives

In this case, optical fiber is used, which makes these models very efficient in terms of cutting depth. In fact, the actions resemble solid-state devices - close relatives. But more efficient and more expensive.

Gas cutters

The gases used are nitrogen, carbon dioxide, maybe helium. These models are much more efficient than the two previous types. They cut everything - from polymers and rubber to the most "difficult" metals.