Do-it-yourself carpentry machines at home. Do-it-yourself step-by-step instructions for assembling a CNC machine

Complex processing of various materials has long ceased to be the lot of factory shops. Twenty years ago, the maximum that home craftsmen could afford was figured sawing with a jigsaw.

Today, handheld routers and cutting lasers can be easily purchased at the hardware store. Various guides are provided for linear processing. But what about cutting complex shapes?

Elementary tasks can be completed using a template. However this method has disadvantages: firstly, it is necessary to make the template itself, and secondly, the mechanical pattern has restrictions on the size of the roundings. And finally, the error of such devices is too large.

A solution has long been found: a CNC machine allows you to cut out such complex shapes from plywood with your own hands, which “jigsaw operators” can only dream of.

The device is a system of coordinate positioning of the cutting tool, controlled by a computer program. That is, the processing head moves along the workpiece, in accordance with a given trajectory. Accuracy is only limited by the size of the cutting attachment (cutter or laser beam).


The possibilities of these machines are endless. There are models with two-dimensional and three-dimensional positioning. However, their cost is so high that the acquisition can only be justified by commercial use. It remains to assemble the CNC machine with your own hands.

How the coordinate system works

The basis of the machine is a powerful frame. The basis is a perfectly flat surface. It also serves as a desktop. The second basic element is the carriage on which the tool is fixed. It can be a dremel, a hand router, a laser gun - in general, any device capable of processing a workpiece. The carriage must move strictly in the plane of the frame.

Let's start with a 2D setup.

As a frame (base) for a do-it-yourself CNC machine, you can use the surface of the table. Most importantly, after adjusting all the elements, the structure no longer moves, remaining rigidly screwed to the base.

To move in one direction (let's call it X), two guides are placed. They must be strictly parallel to each other. A bridge structure is installed across, also consisting of parallel guides. The second axis is Y.


By setting the movement vectors along the X and Y axes, you can set the carriage (and with it the cutting tool) to any point on the plane of the desktop with high accuracy. By choosing the ratio of movement speeds along the axes, the program makes the tool move continuously along any, the most complex trajectory.

The frame of the CNC machine is made by the hands of a craftsman, video

There is another concept: the carriage with the tool is fixed motionless, the work table moves with the workpiece. There is no fundamental difference. Unless the dimensions of the base (and therefore the workpiece) are limited. But the circuit for supplying power to the working tool is simplified, there is no need to worry about flexible power cables.

This is my first CNC machine assembled with my own hands from available materials. The cost of the machine is about $170.

I dreamed of assembling a CNC machine for a long time. Basically, I need it for cutting plywood and plastic, cutting some details for modeling, homemade and other machines. My hands itched to assemble the machine for almost two years, during which time I collected parts, electronics and knowledge.

The machine is budget, its cost is minimal. Further, I will use words that may seem very scary to an ordinary person and this can scare away from self-building a machine, but in fact it is all very simple and easy to master in a few days.

Electronics assembled on Arduino + GRBL firmware

The mechanics are the simplest, plywood frame 10mm + screws and bolts 8mm, linear guides from a metal corner 25 * 25 * 3 mm + bearings 8 * 7 * 22 mm. The Z axis runs on an M8 stud and the X and Y axes on T2.5 belts.

The CNC spindle is homemade, assembled from a brushless motor and a collet clamp + toothed belt drive. It should be noted that the spindle motor is powered by a 24 volt main power supply. The specifications indicate that the motor is 80 amps, but in reality it consumes 4 amps under serious load. I can’t explain why this is happening, but the motor works fine and does its job.

Initially, the Z axis was on self-made linear guides from angles and bearings, later I redid it, pictures and description below.

The working space is about 45 cm in X and 33 cm in Y, 4 cm in Z. Considering the first experience, I will make the next machine with large dimensions and I will put two motors on the X axis, one from each side. This is due to the large shoulder and the load on it when work is carried out at the maximum distance along the Y axis. Now there is one motor and this leads to distortion of the parts, the circle turns out to be a little elliptical due to the resulting deflection of the carriage along X.

The native bearings of the motor quickly loosened up, because they were not designed for lateral load, but it is serious here. Therefore, I installed two large bearings with a diameter of 8 mm on top and bottom on the axle, this should have been done immediately, now there is vibration because of this.

Here in the photo you can see that the Z-axis is already on other linear guides, the description will be below.

The guides themselves have a very simple design, I somehow accidentally found it on Youtube. Then this design seemed to me ideal from all sides, a minimum of effort, a minimum of parts, simple assembly. But as practice has shown, these guides do not work for long. The photo shows what kind of groove formed on the Z axis after a week of my test runs of the CNC machine.

I replaced the homemade z-axis rails with furniture ones that cost less than a dollar for two. I shortened them, left a stroke of 8 cm. There are still old guides on the X and Y axes, I won’t change them yet, I plan to cut parts for a new machine on this machine, then I’ll just disassemble this one.

A few words about cutters. I have never worked with CNC and have very little experience in milling. I bought several cutters in China, all have 3 and 4 grooves, later I realized that these cutters are good for metal, other cutters are needed for milling plywood. While new cutters cover the distance from China to Belarus, I am trying to work with what I have.

The photo shows how a 4 mm cutter burned on 10 mm birch plywood, I still didn’t understand why, the plywood was clean, and on the cutter there was soot similar to pine resin.

Further on the photo there is a 2 mm four-start cutter after an attempt to mill plastic. This piece of molten plastic was then very poorly removed, biting off a little bit with wire cutters. Even at low speeds, the cutter still gets stuck, 4 grooves are clearly for metal :)

The other day my uncle had a birthday, on this occasion I decided to make a gift on my toy :)

As a gift, he made a full house of plywood. First of all, I tried to mill on foam plastic in order to check the program and not spoil the plywood.

Due to backlashes and deflections, the horseshoe was cut out only from the seventh time.

In total, this full house (in its pure form) was milled for about 5 hours + a lot of time for what was spoiled.

Somehow I published an article about the key holder, below in the photo is the same key holder, but already cut on a CNC machine. Minimum effort, maximum accuracy. Due to the backlash, the accuracy is certainly not the maximum, but I will make the second machine more rigid.

And I also cut gears out of plywood on a CNC machine, it's much more convenient and faster than cutting with a jigsaw with my own hands.

Later I also cut out square gears from plywood, they actually spin :)

The results are positive. Now I will develop a new machine, I will cut out parts already on this machine, manual labor is practically reduced to assembly.

You need to master the cutting of plastic, because work on a homemade robot vacuum cleaner got up. Actually, the robot also pushed me to create my own CNC. For the robot, I will cut gears and other parts from plastic.

Update: Now I buy straight cutters with two edges (3.175*2.0*12 mm), they cut without severe scuffing on both sides of the plywood.

For most home craftsmen, the manufacture of such an assembly as a do-it-yourself CNC milling machine is something at the level of a fantastic plot, because such machines and mechanisms are complex in design, constructive and electronic understanding of the device.

However, having at hand the necessary documentation, as well as the required materials, fixtures, it is quite possible to make a mini-milling home-made machine equipped with a CNC with your own hands.

This mechanism is distinguished by the accuracy of the processing performed, the ease of control of mechanical and technological processes, as well as excellent indicators of productivity and product quality.

Principle of operation

Innovative computer-controlled block milling machines designed for complex patterns on semi-finished products. The design must have an electronic component. Together, this will allow you to automate work processes to the maximum.

To model milling mechanisms, you first need to familiarize yourself with the fundamental elements. The cutter acts as an actuating element, which is mounted in a spindle located on the shaft of an electric motor. This part is fixed on the base. It is capable of moving in two coordinate axes: X and Y. Design and install a support table to fix the workpieces.

The electric adjustment unit articulates with the electric propulsion motors. They will ensure the movement of the carriage relative to the workpieces or semi-finished products being processed. Using a similar technology, a 3D graphic image is made on wooden planes.

The sequence of work performed by this CNC mechanism:

1. Writing a working program, due to which the movements of the working body will be performed. For this procedure, it is best to use specialized electronic systems designed to adapt in "handicraft" copies.
2. Mounting semi-finished products on the table.
3. Software output to the CNC.
4. Starting mechanisms, controlling the passage of automatic manipulations of equipment.

To get the maximum level of automation in 3D mode, correctly complete the diagram and label certain components. Experts strongly advise to initially study production copies before starting to build a milling machine with your own hands.

Scheme and drawing

Scheme of a CNC milling machine

The most critical phase in the manufacture of a home-made analogue is the search for the optimal course of equipment manufacturing. It directly depends on the overall characteristics of the workpieces being processed and the need to achieve a certain quality in processing.

For the need to obtain all the necessary functions of the equipment, the best option is to make a mini-milling machine with your own hands. Thus, you will be sure not only of the assembly and its quality, but also of the technological properties, it will be known in advance how to maintain it.

Transmission components

The most successful option is to design 2 carriages moving along perpendicular axes X and Y. It is better to use polished metal rods as a frame. Mobile mobile carriages are “dressed” on them. For the correct manufacture of the transmission, prepare stepper motors, as well as a set of screws.

For improved automation of the workflows of CNC milling machines, designed by oneself, it is required to immediately complete the electronic component to the smallest detail. It is divided into the following components:

• used to conduct electrical energy to stepper motors and power the controller chip. Running is considered modification 12v 3A;
• its purpose is to give commands to the engines. For the correct execution of all specified operations of a CNC milling machine, it will be enough to use a simple scheme to monitor the performance of 3 engines;
• drivers (software). It is also an element for adjusting the movable mechanism.

Video: do-it-yourself CNC milling machine.

Accessories for a homemade milling machine

The next, and crucial step in the construction of milling equipment is the selection of components for building a home-made unit. The best way out of this situation is the use of improvised parts and devices. It is possible to take solid wood species (beech, hornbeam), aluminum / steel or organic glass as the basis for desktop copies of 3D machines.

For the normal operation of the complex as a whole, the development of the design of calipers is required. At the moment of their movement, oscillations are not unacceptable, this will cause incorrect milling. Therefore, before assembly, the components are checked for reliable operation.

Practical tips for choosing the components of a CNC milling machine:

• guides - well-polished steel bars Ø12 mm are used. The length of the X axis is about 200 mm, Y - 100 mm;
• caliper mechanism, optimal material - textolite. Standard site dimensions are 30×100×50 mm;
• stepper motors - engineering experts advise using samples from a 24v, 5A printing device. They have a fairly significant power;
• a block for fixing the working body, it can also be built using textolite. The configuration is directly dependent on the tool that is available.

The procedure for building CNC milling equipment

After completing the selection of all the necessary components, you can completely easily build an oversized milling mechanism equipped with CNC with your own hands. Before proceeding with the direct design, we once again check the components, control their parameters and workmanship. This will further help to avoid premature failure of the mechanism chain.

For reliable fixation of equipment components, specialized fasteners are used. Their design and execution directly depend on the future scheme.

The list of necessary steps to assemble a small CNC equipment to perform the milling process:

1. Mounting the guide axles of the support element, fixing on the extreme parts of the machine.
2. Grinding calipers. It is required to move along the guides until a smooth movement is formed.
3. Tightening the screws to fix the support device.
4. Fastening components to the base of the working mechanism.
5. Mounting lead screws and couplings.
6. Installation of marching motors. They are attached to the coupling bolts.

Electronic components are located in a self-contained cabinet. This ensures the minimization of failures in performance in the process of carrying out technological operations with a milling cutter. The plane for mounting the working machine must be without drops, because the design does not provide for leveling screws.

After completing the above, proceed to perform trial tests. First you need to install a light program to perform milling. In the process of work, it is necessary to continuously check all passes of the working body (cutter). Parameters that are subject to constant control: the depth and width of processing. This applies especially to 3D processing.

Thus, referring to the information written above, making milling equipment with your own hands provides a whole list of advantages over conventional purchased counterparts. Firstly, this design will be suitable for the expected volumes and types of work, secondly, maintainability is ensured, since it is built from improvised materials and fixtures, and, thirdly, this equipment option is inexpensive.

Having experience in designing such equipment, further repairs will not take much time, downtime will be reduced to a minimum. Such equipment can be useful to your neighbors in their summer cottage to carry out their own repairs. By renting such equipment, you will help your close friend in work, count on his help in the future.

Having dealt with the design and functional features of milling machines, as well as the load that will fall on it, you can safely start manufacturing it, based on the practical information given along the text. Design and complete tasks without any problems.

Video: homemade CNC wood milling machine.

Many craftsmen often think about building a homemade CNC machine. It has a number of advantages and will allow you to solve a large number of tasks more efficiently and quickly.

Carry out milling and cutting of almost all materials. In this regard, the temptation to manufacture such a device is quite large. Maybe it's time to take matters into your own hands and replenish your workshop with new equipment?

Machine tools with numerical control are widely used not only in industrial production, but also in private workshops. They allow flat and profile processing of metal, plastic and wood.

In addition, they are indispensable when performing engraving and drilling and welding work.

Almost any task solved with the use of such devices is performed at a high level.

If you need to draw something on a board or a wooden plate, it is enough to create a layout in a computer program and transfer it to the product using CNC Milling. It is simply impossible to perform such an operation manually in most cases, especially when it comes to high accuracy.

All professional equipment of this type is characterized by a high level of automation and ease of operation. Only basic skills in specialized computer programs are needed to solve simple material processing tasks.

At the same time, even CNC cope with their goals. With proper tuning and the use of high-quality nodes, you can achieve good accuracy from the device, minimal backlash and acceptable speed.

DIY CNC machine

Functional diagram of a CNC machine.

So, how to make this device? To make a CNC machine with your own hands, you need to spend time developing a project, as well as familiarize yourself with existing factory models. By following these first and simplest rules, you will be able to avoid the most common mistakes.

It should be noted that the CNC milling machine is a technically complex device with electronic elements. Because of this, many people believe that it is impossible to make it by hand.

Of course, this opinion is wrong. However, it must be borne in mind that the assembly will require not only a drawing, but also a certain set of tools and parts. For example, you will need a stepper motor, which can be taken from a printer, etc.

It should also take into account the need for certain financial and time costs. If such problems are not terrible, then it will not be difficult to make an affordable and efficient unit with coordinate positioning of the cutting tool for processing metal or wood.

Scheme

The most difficult stage of CNC for metal and wood is the choice of the optimal equipment scheme. Here everything is determined by the size of the workpiece and the degree of its processing.

For domestic purposes, it is better to give preference to a drawing of a small device with the necessary set of functions.

One option could be a design consisting of two carriages that will move in a plane. Steel sanding bars are great as a base. Carriages are attached to them.

You will also need a stepper motor and screws with rolling bearings to provide a transmission. The CNC router will be controlled by the program.

Training

To automate a homemade CNC milling machine, it is necessary to think through the electronic part as much as possible.

Drawing of a homemade machine.

It can be divided into several elements:

• power supply unit that supplies electricity to the stepper motor and controller;
• controller;
• driver that regulates the operation of the moving parts of the structure.

Then, to build the machine itself, you need to pick up assembly parts. It is best to use improvised materials. This will help keep the costs of the tools you need as low as possible.

The base is usually made of wood, plexiglass or metal. It is important that during the movement of the calipers there are no vibrations. They will lead to inaccurate operation of the device. In this regard, it is necessary to properly develop their design.

Here are some tips for choosing parts:

• rods with a diameter of up to 12 mm are suitable as guides;
• the best option for a caliper would be textolite;
• SD is usually taken from printers;
• the block for fixing the cutter is also made of textolite.

Assembly instructions

After preparing and selecting the parts, you can begin to assemble the milling unit for processing wood and metal.

First of all, you should once again check all the components and make sure that their dimensions are correct.

Scheme of the CNC device.

The assembly order is approximately as follows:

• installation of caliper guides, their fastening to the side surfaces of the structure;
• lapping the calipers as a result of their movement until a smooth ride can be achieved;
• bolt tightening;
• installation of components on the basis of the device;
• fastening lead screws with couplings;
• fastening to the screws of the couplings of stepper motors.

The entire electronic component should be placed in a separate unit. Thus, the possibility of failure during operation will be minimized. Such an option for placing electronics can be called the best design.

Features of work

After the CNC has been assembled with your own hands, you can start testing.

The software will control the actions of the machine. It must be chosen correctly. First of all, it is important that the program is working. Secondly, it should maximize all the capabilities of the equipment.

Kinematic diagram of the device operation.

The software must contain all the necessary drivers for the controllers.

You should start with simple programs. During the first runs, it is necessary to monitor each cut of the cutter to make sure that the processing is correct in width and depth. It is especially important to control the three-dimensional versions of such devices.

Outcome

Numerically controlled wood processing devices have various electronics in their design. Because of this, at first glance, it may seem that such equipment is very difficult to manufacture independently.

In fact, do-it-yourself CNC is a feasible task for everyone. It is enough just to believe in yourself and in your strength, and then you can become the owner of a reliable and efficient milling machine, which will become the pride of any master.

For many projects, a CNC router is essential for good and fast results. After some research on the current CNC machines, I came to the conclusion that all machines under 150k cannot meet my needs in terms of space and precision.

What I want:

• working space 900 x 400 x 120 mm
• relatively quiet spindle with high power at low speeds
• highest possible rigidity (for milling aluminum parts)
• highest possible accuracy
• USB interface
• spend up to 150 thousand rubles

With these requirements, I started 3D designing with schematics and drawings, testing the many parts available. The main requirement: the parts must be combined with each other. In the end I decided to build the machine on a 30-B type nut with 8 aluminum frames with 16mm ball bearing spindles, 15mm ball bearing guides and 3 amp NEMA23 stepper motors that fit easily into a pre-built mounting system.

These parts fit together perfectly without the need for special parts.

Step 1: Building the Frame

The key is good planning...

Parts arrived a week after ordering. And in a few minutes, the X-axis was ready. - Easier than I thought! The 15mm HRC linear bearings are of very good quality and once installed you immediately know that they will perform very well.

After 2 hours, when assembling a CNC machine on Arduino with my own hands, the first problem appeared: the spindles do not want to get into roller bearings. My freezer isn't big enough for 1060mm spindles, so I decided to get some dry ice, which meant putting the project on hold for a week.

Step 2: Spindle setup

A friend came in with a bag of dry ice, and after a few minutes of freezing, the spindles fit perfectly into the roller bearings. A few more screws and it looks a bit like a CNC machine.

Step 3: Electrical Parts

The mechanical part is finished and I'm moving on to the electrical parts.

Since I am very familiar with Arduino and want to have full control over USB, I first chose an Arduino Uno with a GRBL shield and TB8825 steppers. This configuration works very simply and after a little tweaking the machine is PC manageable. Excellent!

But since the TB8825 runs at max 1.9A and 36V (gets very hot), it's enough to start the car, but I noticed a step loss due to too little power. A long milling process at this temperature is a nightmare.

I bought a cheap TB6560 from China (300 rubles each, 3 weeks delivery) and connected them to the GRBL shield. The voltage ratings are not very accurate for this board, you will find ratings from 12V to 32V. Since I already have a 36V power supply, I tried to adapt it.

Result: Two stepper drives work fine, one cannot handle the higher voltage and the other only turns in one direction (cannot change direction).

So, again in search of a good driver ...

TB6600 is my final decision. It is completely covered with an aluminum cooling cover and is easy to set up. Now my steppers work on the X and Y axes with 2.2A and on the Z axis with 2.7A. I could go up to 3A, but since I have a closed box to protect the circuits from aluminum dust, I decided to use 2.2A, which is enough for my needs and generates almost no heat. Also, I don't want the steppers to destroy the car if they make a mistake when I give them too much power.

I thought for a long time about a solution to protect the stepper power supply and frequency converter from small aluminum parts. There are many solutions where the transducer is mounted very high or at a sufficient distance from the milling machine. The main problem is that these devices generate a lot of heat and need active cooling. My final decision is my girlfriend's beautiful pantyhose. I cut them into 30 cm pieces and used them as a protective hose, which is very simple and provides good airflow.

Step 4: Spindle

Choosing the right spindle requires a lot of research. At first I thought about using a stock Kress1050 spindle, but since it only has 1050 watts at 21000 rpm, I can't expect much power at lower speeds.

For my requirements for dry milling aluminum and possibly some steel parts, I need 6000-12000 RPM power.

That's why I finally chose a 3kW variable frequency drive from China (together with a converter) for 25 thousand rubles.

The quality of the spindle is very good. It is quite powerful and easy to set up. I underestimated the weight at 9kg, but fortunately my frame is strong enough and there is no problem with a heavy spindle. (High weight is the reason for the 2.7A Z-axis drive)

Step 5: Job Completed

Ready. The machine works very well, I had a few problems with the stepper drivers, but overall I'm really happy with the result. I spent about 120 thousand rubles and I have a car that exactly suits my needs.

The first milling project was a negative shape in POM (Parallax occlusion mapping). The machine did a great job!

Step 6: Finishing for aluminum milling

Already in POM, I saw that the torque on the Y-bearing is a little high and the machine bends with high forces around the Y axis. That's why I decided to buy a second rail and upgrade the portal accordingly.

After that, there is almost no backlash due to the force on the spindle. An excellent upgrade and, of course, worth the money (10 thousand rubles).

Now I'm ready for aluminum. With AlMg4.5Mn I got very good results without any cooling.

Step 7: Conclusion

Building your own CNC machine is not really rocket science. I have relatively poor working conditions and equipment, but with a good work plan all I need is a few bits, a screwdriver, clamps and a regular drill press. One month in CAD and purchase plan, and four months of assembly to complete installation. The creation of the second machine would have gone much faster, but without any prior knowledge in this area, I had to learn a lot about mechanics and electronics during this time.

Step 8: Details

Here you can find all the main parts of the machine. I would recommend AlMg4.5Mn alloys for all aluminum plates.

Electrical:
I bought all electrical parts on ebay.

• Arduino + GRBL-Shield: ~ 1500 rub.
• Stepper driver: 1000 rub.\pcs
• Power supply: 3000 rubles.
• Stepper motors: ~ 1500 rubles \ pcs
• Milling spindle + inverter: 25 thousand rubles.

Mechanical:

• Linear bearings: link
• Linear rails: link
• Ball circulation spindles: link
• 2x1052mm
• 1x600mm
• 1x250mm
• Fixed spindle bearings + stepper holder: link
• Floating bearing: link
• Spindle-step connections: I ordered Chinese couplings for 180 rubles / piece

• Bottom profiles: link
• X-profiles for rails: link
• Y-profiles for installing X-axis stepper/spindle: link

Portal:

• Profile on linear bearing X: link
• Rear panel / Mounting plate: 5 mm aluminum plate 600×200.
• Y-profiles: 2x link
• Z-profile: link
• Z-mounting plate: 5mm 250×160 Aluminum plate
• Z-sliding plate for spindle mounting: 5mm 200×160 Aluminum plate

Step 9: Software

After using CAD, then CAM and finally G-Code Sender I am very disappointed. After a long search for good software, I settled on Estlcam, which is very convenient, powerful and very affordable (3 thousand rubles).

It completely overwrites the Arduino and controls stepper motors on its own. There are many good documented features. The trial version provides the full functionality of the software, just adding a wait time.

For example, edge search. You just need to connect the wire to the Arduino A5 pin and to the workpiece (if not metal, then use aluminum foil to temporarily cover it). With machine control, you can now press the milling tool against the work surface. As soon as the circuit closes, the machine stops and sets the axle to zero. Very useful! (usually grounding is not required because the spindle must be grounded)

Step 10: Improve

Until now, the Y and Z axes had temporary plastic brackets to transmit the forces of the spindle nuts and moved the milling spindle accordingly.

The plastic braces were hard plastic, but I don't trust them too much. Imagine that the Z-axis bracket will brake, the milling spindle will simply fall (obviously in the process of milling).

That is why I have now made these brackets from aluminum alloy (AlMgSi). The result is attached in the picture. They are now much stronger than the plastic version I made before without a router.

Step 11: Machine in operation

Now, with a little CNC practice, a do-it-yourself woodworking machine already gives very good results (for a hobby). These pictures show an AlMg4.5Mn nozzle. I had to mill it from both sides. In the last photo, what happened without polishing or sandpaper.

I used a 6mm VHM cutter with 3 blades. I found that 4-6mm tools give very good results on this machine.