The goal of this project is to create a desktop CNC machine. It was possible to buy a ready-made machine, but its price and dimensions did not suit me, and I decided to build a CNC machine with the following requirements:
- usage simple tools(you only need drilling machine, band-saw and hand tools)
- low cost (I was focusing on low cost, but still bought elements for about $600, you can save a lot by buying elements in relevant stores)
- small footprint (30"x25")
- normal working space (10" along the X axis, 14" along the Y axis, 4" along the Z axis)
- high speed cutting (60" per minute)
- small number of elements (less than 30 unique)
- available elements (all elements can be purchased in one hardware store and three online stores)
- possibility of successful processing of plywood
Other people's machines
Here are a few photos of other machines collected from this article
Photo 1 – Chris and a friend assembled the machine, cutting out parts from 0.5" acrylic using laser cutting. But everyone who has worked with acrylic knows that laser cutting this is good, but acrylic doesn't hold up well to drilling and there are a lot of holes in this project. They did Good work, more information can be found on Chris's blog. I especially enjoyed making a 3D object using 2D cuts.
Photo 2 - Sam McCaskill did a really good one table machine with CNC. I was impressed that he did not simplify his work and cut all the elements by hand. I'm impressed with this project.
Photo 3 - Angry Monk's used laser-cut DMF parts and toothed-belt motors converted into propeller motors.
Photo 4 - Bret Golab's assembled the machine and configured it to work with Linux CNC (I also tried to do this, but could not due to the complexity). If you are interested in his settings, you can contact him. He did a great job!
I'm afraid I don't have enough experience and knowledge to explain the basics of CNC, but the CNCZone.com forum has an extensive section dedicated to homemade machines, which has helped me a lot.
Cutter: Dremel or Dremel Type Tool
Axes parameters:
X axis
Travel Distance: 14"
Speed: 60"/min
Acceleration: 1"/s2
Resolution: 1/2000"
Pulses per inch: 2001
Y axis
Travel Distance: 10"
Drive: Toothed belt drive
Speed: 60"/min
Acceleration: 1"/s2
Resolution: 1/2000"
Pulses per inch: 2001
Z axis (up-down)
Travel Distance: 4"
Drive: Screw
Acceleration: .2"/s2
Speed: 12"/min
Resolution: 1/8000"
Pulses per inch: 8000
Required Tools
I aimed to use popular tools that can be purchased at a regular DIY store.
Power tools:
- band saw or jigsaw
- drilling machine (drills 1/4", 5/16", 7/16", 5/8", 7/8", 8mm (about 5/16"), also called Q
- Printer
- Dremel or similar tool (for installation into a finished machine).
Hand tool:
- rubber hammer(for placing elements in place)
- hexagons (5/64", 1/16")
- screwdriver
- glue stick or spray glue
- adjustable wrench (or socket wrench with ratchet and 7/16" socket)
Necessary materials
The attached PDF file (CNC-Part-Summary.pdf) provides all costs and information about each item. Only generalized information is provided here.
Sheets --- $20
-Piece 48"x48" 1/2" MDF (any sheet material 1/2" thick I plan to use UHMW in the next version of the machine, but now it is too expensive)
-Piece of 5"x5" 3/4" MDF (this piece is used as a spacer, so you can take a piece of any 3/4" material
Motors and Controllers --- $255
-You could write a whole article about the choice of controllers and motors. In short, you need a controller capable of driving three motors and motors with torque of around 100 oz/in. I bought the motors and a ready-made controller and everything worked well.
Hardware --- $275
-I bought these items in three stores. Simple elements I bought it at a hardware store, I bought specialized drivers at McMaster Carr (http://www.mcmaster.com), and I bought bearings, which I need a lot of, from an online seller, paying $40 for 100 pieces (it turns out to be quite profitable, a lot bearings are left for other projects).
Software ---(Free)
-You need a program to draw your design (I use CorelDraw), and now I'm using trial version Mach3, but I have plans to move to LinuxCNC (an open source machine controller using Linux)
Head unit --- (optional)
-I installed Dremel on my machine, but if you are interested in 3D printing (eg RepRap) you can install your own device.
Printing templates
I had some experience with a jigsaw, so I decided to glue down the templates. Need to print PDF files with the templates placed on the sheet, glue the sheet onto the material and cut out the parts.
File name and material:
All: CNC-Cut-Summary.pdf
0.5" MDF (35 8.5"x11" template sheets): CNC-0.5MDF-CutLayout-(Rev3).pdf
0.75" MDF: CNC-0.75MDF-CutLayout-(Rev2).pdf
0.75" aluminum tube: CNC-0.75Alum-CutLayout-(Rev3).pdf
0.5" MDF (1 48"x48" Pattern Sheet): CNC-(One 48x48 Page) 05-MDF-CutPattern.pdf
Note: I am attaching the CorelDraw drawings in the original format (CNC-CorelDrawFormat-CutPatterns (Rev2) ZIP) for those who would like to change something.
Note: There are two file options for MDF 0.5". You can download a file with 35 pages 8.5"x11" (CNC-0.5MDF-CutLayout-(Rev3), PDF), or a file (CNC-(One 48x48 Page) 05- MDF-CutPattern.pdf) with one sheet of 48"x48" for printing on a wide format printer.
Step by step:
1. Download three PDF template files.
2. Open each file in Adobe Reader
3. Open the print window
4. (IMPORTANT) disable Page Scaling.
5. Check that the file has not been accidentally scaled. The first time I didn't do this, I printed everything at 90% scale, as described below.
Gluing and cutting out elements
Glue the printed templates onto the MDF and aluminum pipe. Next, simply cut out the part along the contour.
As mentioned above, I accidentally printed the templates at 90% scale and didn't notice until I started cutting. Unfortunately, I didn't realize this until this stage. I was left with 90% scale templates and after moving across the country I had access to a full size CNC machine. I couldn't resist and cut out the elements using this machine, but I couldn't drill them from the back side. That is why all the elements in the photographs are without pieces of the template.
Drilling
I didn't count exactly how many, but this project uses a lot of holes. The holes that are drilled at the ends are especially important, but take your time on them and you will rarely need to use a rubber hammer.
Places with holes in the overlay on top of each other are an attempt to make grooves. Perhaps you have a CNC machine that can do this better.
If you have made it this far, then congratulations! Looking at a bunch of elements, it is quite difficult to imagine how to assemble the machine, so I tried to make detailed instructions, similar to the instructions for LEGO. (Attached PDF CNC-Assembly-Instructions.pdf). The step-by-step photos of the assembly look quite interesting.
Ready!
The machine is ready! I hope you got it up and running. I hope the article didn't miss important details and moments. Here's a video showing the machine cutting out a pattern on pink foam board.
Complex processing various materials has long ceased to be the lot of factory floors. Twenty years ago, the most that home craftsmen could afford was figure cutting with a jigsaw.
Today, hand-held milling cutters and cutting lasers can easily be purchased at a household tool store. Various guides are provided for linear processing. What about cutting out complex shapes?
Basic tasks can be accomplished using a template. However this method has disadvantages: firstly, you need to make the template itself, and secondly, the mechanical pattern has limitations on the size of the curves. And finally, the error of such devices is too great.
A solution has long been found: a CNC machine allows you to cut out such things from plywood with your own hands complex figures, which “jigsaw operators” can only dream of.
The device is a coordinate positioning system cutting tool controlled by a computer program. That is, the processing head moves along the workpiece in accordance with a given trajectory. Accuracy is limited only by the size of the cutting attachment (mill or laser beam). 
The possibilities of such machines are endless. There are models with two-dimensional and three-dimensional positioning. However, their cost is so high that the purchase can only be justified by commercial use. All that remains is to assemble the CNC machine with your own hands.
The principle of operation of the coordinate system
The basis of the machine is a powerful frame. The basis is a perfectly flat surface. It also serves as a work desk. Second base element- This is the carriage on which the tool is mounted. It could be a Dremel manual frezer, laser gun - in general, any device capable of processing a workpiece. The carriage must move strictly in the plane of the frame.
First, let's look at a two-dimensional setup
You can use the table surface as a frame (base) for a DIY CNC machine. The main thing is that after all the elements are adjusted, the structure no longer moves, remaining firmly 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, also consisting of parallel guides, is installed across it. The second axis is Y. 
By specifying the movement vectors along the X and Y axes, you can high accuracy install the carriage (and with it the cutting tool) at any point on the plane of the workbench. By choosing the ratio of movement speeds along the axes, the program forces the tool to move continuously along any, even the most complex, trajectory.
Knowing what is complex technical and electronic device, many craftsmen think that it is simply impossible to make it with your own hands. However, this opinion is wrong: do it yourself similar equipment it is possible, but for this you need to have not only it detailed drawing, but also a set necessary tools and related components.
Processing a duralumin blank on a homemade desktop milling machine
When deciding to make your own CNC machine, keep in mind that it can take a significant amount of time. In addition, certain financial expenses. However, by not being afraid of such difficulties and by correctly approaching all issues, you can become the owner of affordable, efficient and productive equipment that allows you to process workpieces from various materials with high degree accuracy.
To do milling machine equipped with a CNC system, you can use two options: buy a ready-made kit, from which such equipment is assembled from specially selected elements, or find all the components and assemble a device with your own hands that fully satisfies all your requirements.
Instructions for assembling a homemade CNC milling machine
Below in the photo you can see the made with my own hands, to which is attached detailed instructions on manufacturing and assembly, indicating the materials and components used, exact “patterns” of machine parts and approximate costs. The only negative is the instructions on English language, but it is quite possible to understand the detailed drawings without knowing the language.
Download free instructions for making the machine:
The CNC milling machine is assembled and ready to go. Below are some illustrations from the assembly instructions for this machine.
“Patterns” of machine parts (reduced view) Beginning of machine assembly Intermediate stage The final stage assemblies
Preparatory work
If you decide that you will design a CNC machine with your own hands, without using ready set, then the first thing you will need to do is choose schematic diagram, according to which such mini-equipment will work.
As a basis milling equipment With CNC, you can take an old drilling machine, in which the working head with the drill is replaced with a milling one. The most difficult thing that will have to be designed in such equipment is the mechanism that ensures the movement of the tool in three independent planes. This mechanism can be assembled using carriages from a non-working printer; it will ensure the movement of the tool in two planes.
It is easy to connect software control to a device assembled according to this concept. However, its main disadvantage is that only workpieces made of plastic, wood and thin materials can be processed on such a CNC machine. sheet metal. This is explained by the fact that the carriages from the old printer, which will ensure the movement of the cutting tool, do not have a sufficient degree of rigidity.
In order for your homemade CNC machine to be able to perform full-fledged milling operations with workpieces made of various materials, a sufficiently powerful stepper motor must be responsible for moving the working tool. It is absolutely not necessary to look for a stepper type motor; it can be made from a conventional electric motor, subjecting the latter to minor modifications.
Using a stepper motor in yours will make it possible to avoid using a screw drive, and functionality and characteristics homemade equipment it won't make things any worse. If you still decide to use carriages from a printer for your mini-machine, then it is advisable to select them from a larger model of the printing device. To transfer force to the shaft of milling equipment, it is better to use not ordinary, but toothed belts that will not slip on the pulleys.
One of the most important components of any such machine is the milling mechanism. It is its production that must be given Special attention. To properly make such a mechanism, you will need detailed drawings, which will need to be strictly followed.
CNC milling machine drawings
Let's start assembling the equipment
The basis of homemade CNC milling equipment can be a beam rectangular section, which must be securely fixed on the guides.
The supporting structure of the machine must have high rigidity; when installing it, it is better not to use welded joints, and all elements need to be connected only with screws.
This requirement is explained by the fact that welded seams very poorly withstand vibration loads, to which they will necessarily be subjected Basic structure equipment. Such loads will ultimately lead to the fact that the machine frame will begin to collapse over time, and changes will occur in it geometric dimensions, which will affect the accuracy of equipment setup and its performance.
Welds when installing the frame of a homemade milling machine often provoke the development of play in its components, as well as deflection of the guides, which occurs under heavy loads.
The milling machine that you will assemble with your own hands must have a mechanism that ensures the movement of the working tool in the vertical direction. It is best to use a screw gear for this, the rotation of which will be transmitted using a toothed belt.
An important part of a milling machine is its vertical axis, which homemade device can be made from aluminum plate. It is very important that the dimensions of this axis are precisely adjusted to the dimensions of the device being assembled. If you have a muffle furnace at your disposal, then make vertical axis You can make the machine yourself by casting it from aluminum according to the dimensions indicated in the finished drawing.
Once all the components of your homemade milling machine are prepared, you can begin assembling it. Begins this process from the installation of two stepper motors, which are mounted on the equipment body behind its vertical axis. One of these electric motors will be responsible for moving milling head in the horizontal plane, and the second - for moving the head, respectively, in the vertical. After this, the remaining components and assemblies of home-made equipment are installed.
Rotation to all components of homemade CNC equipment should be transmitted only through belt drives. Before connecting to assembled machine program control system, you should check its performance in manual mode and immediately eliminate all identified deficiencies in its operation.
You can watch the assembly process in the video, which is easy to find on the Internet.
Stepper motors
The design of any CNC-equipped milling machine must include stepper motors, which provide movement of the tool in three planes: 3D. When designing a homemade machine for this purpose, you can use electric motors installed in a dot matrix printer. Most older models of dot matrix printing devices were equipped with electric motors that had sufficient high power. In addition to stepper motors, it is worth taking strong steel rods from an old printer, which can also be used in the design of your homemade machine.
To make your own CNC milling machine, you will need three stepper motors. Since there are only two of them in the dot matrix printer, it will be necessary to find and disassemble another old printing device.
It will be a big plus if the motors you find have five control wires: this will significantly increase the functionality of your future mini-machine. It is also important to find out the following parameters of the stepper motors you have found: how many degrees are rotated in one step, what is the supply voltage, as well as the value of the winding resistance.
The drive design of a homemade CNC milling machine is assembled from a nut and a stud, the dimensions of which should be pre-selected according to the drawing of your equipment. To fix the motor shaft and attach it to the stud, it is convenient to use a thick rubber winding from electric cable. Parts of your CNC machine, such as clamps, can be made in the form of a nylon sleeve into which a screw is inserted. In order to make such simple structural elements, you will need a regular file and a drill.
Electronic equipment
Your DIY CNC machine will be controlled by software, and it needs to be selected correctly. When choosing such software (you can write it yourself), it is important to pay attention to the fact that it is operational and allows the machine to realize all its functionality. Such software must contain drivers for the controllers that will be installed on your mini-milling machine.
In a homemade CNC machine, an LPT port is required, through which electronic system control and connects to the machine. It is very important that such connection is made through installed stepper motors.
When choosing electronic components for your homemade machine, it is important to pay attention to their quality, since the accuracy of the technological operations that will be performed on it will depend on this. After installing and connecting all electronic components of the CNC system, you need to download the necessary software and drivers. Only after this is a test run of the machine, checking the correct operation of it under the control of loaded programs, identifying deficiencies and promptly eliminating them.
So you decided to build homemade CNC a milling machine or maybe you’re just thinking about it and don’t know where to start? There are many benefits to having a CNC machine. Home machines can mill and cut almost all materials. Whether you are an amateur or a craftsman, this opens up great horizons for creativity. The fact that one of the machines could end up in your workshop is even more tempting.
There are many reasons why people want to build their own DIY CNC router. As a rule, this happens because we simply cannot afford to buy it in a store or from a manufacturer, and this is not surprising, because the price for them is rather high. Or you can be like me and have a lot of fun with own work and creating something unique. You can simply do this to gain experience in mechanical engineering.
Personal experience
When I first started developing, thinking through and making the first CNC router with my own hands, it took about one day to create the project. Then, when I started buying parts, I did some research. And I found some information in various sources and forums, which led to the emergence of new questions:
- Do I really need ball screws, or will regular studs and nuts work just fine?
- Which linear bearing is best and can I afford it?
- What motor parameters do I need, and is it better to use a stepper or a servo drive?
- Does the housing material deform too much when large size machine?
- And so on.
Fortunately, I was able to answer some of the questions thanks to my engineering and technical background left after my studies. However, many of the problems I would encounter could not be calculated. I just needed someone with practical experience and information on this issue.
Of course, I received many answers to my questions from different people, many of which contradicted each other. Then I had to do more research to figure out which answers were worthwhile and which were garbage.
Every time I had a question that I didn't know the answer to, I had to repeat the same process. By and large, this is due to the fact that I had a limited budget and wanted to take the best that my money could buy. This is the same situation for many people who create a homemade CNC milling machine.
Kits and kits for assembling CNC routers with your own hands
Yes, there are machine kits available for hand assembled, but I have yet to see one that can be tailored to specific needs.
There is also no possibility to make changes to the design and type of machine, but there are many of them, and how do you know which one is right for you? No matter how good the instructions are, if the design is poorly thought out, then the final machine will be poor.
That's why you need to be aware of what you're building and understand the role each piece plays!
Management
This guide aims to prevent you from making the same mistakes that I wasted my precious time and money on.
We'll look at all the components down to the bolts, looking at the advantages and disadvantages of each type of each part. I will talk about every aspect of design and show you how to create a CNC milling machine with your own hands. I'll take you through the mechanics to the software and everything in between.
Keep in mind that homemade CNC machine plans offer few solutions to some problems. This often results in sloppy design or poor machine performance. That's why I suggest you read this guide first.
LET'S START
STEP 1: Key design decisions
First of all, the following questions need to be considered:
- Determining a suitable design specifically for you (for example, if you make a woodworking machine with your own hands).
- Required processing area.
- Availability of work space.
- Materials.
- Tolerances.
- Design methods.
- Available tools.
- Budget.
STEP 2: Base and X-Axis
The following questions are addressed here:
- Design and build the main base or X-axis base.
- Rigidly fixed parts.
- Partially fixed parts, etc.
STEP 3: Design the Gantry Y Axis
- Design and construction of the portal Y axis.
- Breakdown various designs to elements.
- Forces and moments on the portal, etc.
STEP 4: Z Axis Assembly Diagram
The following questions are addressed here:
- Design and assembly of Z axis assembly.
- Forces and moments on the Z axis.
- Linear rails/guides and bearing spacing.
- Selecting a cable channel.
STEP 5: Linear Motion System
This paragraph addresses the following issues:
- A detailed study of linear motion systems.
- Selecting the right system specifically for your machine.
- Design and construction of your own guides on a low budget.
- Linear shaft and bushings or rails and blocks?
STEP 6: Mechanical Drive Components
This paragraph covers the following aspects:
- Detailed overview of drive parts.
- Selecting the right components for your machine type.
- Stepper or servo motors.
- Screws and ball screws.
- Drive nuts.
- Radial and thrust bearings.
- Engine coupling and mount.
- Direct drive or gearbox.
- Racks and gears.
- Calibration of propellers relative to engines.
STEP 7: Selecting Motors
In this step you need to consider:
- Detailed review of CNC motors.
- Types of CNC motors.
- How stepper motors work.
- Types of stepper motors.
- How do servomotors work?
- Types of servo motors.
- NEMA standards.
- Choice the right type engine for your project.
- Measuring motor parameters.
STEP 8: Cutting table design
- Design and build your own tables on a low budget.
- Perforated cutting layer.
- Vacuum table.
- Review of cutting table designs.
- The table can be cut using a CNC wood router.
STEP 9: Spindle Parameters
This step addresses the following issues:
- Review of CNC spindles.
- Types and functions.
- Pricing and costs.
- Mounting and cooling options.
- Cooling systems.
- Creating your own spindle.
- Calculation of chip load and cutting force.
- Finding the optimal feed rate.
STEP 10: Electronics
This paragraph addresses the following issues:
- Control Panel.
- Electrical wiring and fuses.
- Buttons and switches.
- MPG and Jog circles.
- Power supplies.
STEP 11: Program Controller Parameters
This step addresses the following issues:
- Overview of the CNC controller.
- Controller selection.
- Available options.
- Closed-loop and open-loop systems.
- Controllers at an affordable price.
- Creating your own controller from scratch.
STEP 12: Selecting Software
This paragraph addresses the following issues:
- Review of CNC related software.
- Selection of software.
- CAM software.
- CAD software.
- NC Controller software.
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A kit with which you can assemble your own CNC milling machine.
Ready-made machines are sold in China; a review of one of them has already been published on Muska. We will assemble the machine ourselves. Welcome…
UPD: links to files
I will still provide a link to a review of the finished machine from AndyBig. I won’t repeat myself, I won’t quote his text, we’ll write everything from scratch. The title only indicates a set with engines and a driver, there will be more parts, I will try to provide links to everything.
And this... I apologize in advance to the readers, I didn’t take any photos during the process on purpose, because... I wasn’t going to do a review at that moment, but I’ll take as many photos of the process as possible and try to give detailed description all nodes.
The purpose of the review is not so much to brag as to show the opportunity to make an assistant for yourself. I hope with this review to give someone an idea, and perhaps not only repeat it, but also make it even better. Go…
How the idea was born:
It so happened that I have been involved with drawings for a long time. Those. my professional activity closely related to them. But it’s one thing when you make a drawing, and then completely different people bring the design object to life, and quite another thing when you bring the design object to life yourself. And if I seem to be doing okay with construction things, then not so much with modeling and other applied arts.
So, for a long time I had a dream of making a zhzhik out of an image drawn in AutoCAD - and it’s in real life in front of you, you can use it. This idea popped up from time to time, but it couldn’t take shape into anything concrete until...
Until I saw REP-RAP three or four years ago. Well, a 3D printer was a very interesting thing, and the idea of assembling it took me a long time to formulate, I was collecting information about different models, about the pros and cons different options. At one point, following one of the links, I ended up on a forum where people were sitting and discussing not 3D printers, but CNC milling machines. And from here, perhaps, passion begins its journey.
Instead of theory
In a nutshell about CNC milling machines (I write in my own words intentionally, without copying articles, textbooks and manuals).
A milling machine works exactly the opposite of a 3D printer. In the printer, step by step, layer by layer, the model is built up by fusing polymers; in a milling machine, with the help of a cutter, “everything unnecessary” is removed from the workpiece and the required model is obtained.
To operate such a machine, the required minimum is required.
1. Base (case) with linear guides and transmission mechanism (can be a screw or belt)
2. Spindle (I see someone smiled, but that’s what it’s called) - the actual engine with a collet into which the working tool - a milling cutter - is installed.
3. Stepper motors - motors that allow controlled angular movements.
4. Controller - a control board that transmits voltages to the motors in accordance with signals received from the control program.
5. Computer with installed control program.
6. Basic drawing skills, patience, desire and good mood.))
The points:
1. Base.
by configuration:
I will divide it into 2 types, there are more exotic options, but there are 2 main ones:
With movable portal:
Actually, the design I chose, it has a base on which the X-axis guides are fixed. The portal on which the Y-axis guides are located moves along the X-axis guides, and the Z-axis node moves along it.
With a static portal
This design is also a body, which is also a portal on which the Y-axis guides are located, and the Z-axis unit moving along it, and the X-axis is already moving relative to the portal.
According to the material:
the body can be made from different materials, the most common:
- duralumin - has a good ratio of weight and rigidity, but the price (especially for a hobby homemade product) is still depressing, although if the machine is intended to seriously earn money, then there are no options.
- plywood - good rigidity with sufficient thickness, light weight, the ability to process anything :), and the actual price, sheet of plywood 17 is now quite inexpensive.
- steel - often used on machines with large processing areas. Such a machine, of course, must be static (not mobile) and heavy.
- MFD, plexiglass and monolithic polycarbonate, even chipboard - I also saw such options.
As you can see, the design of the machine itself is very similar to both a 3D printer and laser engravers.
I deliberately do not write about the designs of 4, 5 and 6-axis milling machines, because... A homemade hobby machine is on the agenda.
2. Spindle.
Actually, spindles come with air and water cooling.
WITH air cooled in the end they cost less, because for them there is no need to fence an additional water circuit; they operate a little louder than water ones. Cooling is provided by a rear-mounted impeller, which at high speeds creates a noticeable air flow that cools the engine housing. How more powerful engine, the more severe the cooling and the more air flow, which may well inflate in all directions
dust (shavings, sawdust) of the processed product.
Water cooled. Such a spindle works almost silently, but in the end, you still cannot hear the difference between them during the work process, since the sound of the material being processed by the cutter will be covered up. In this case, of course, there is no draft from the impeller, but there is an additional hydraulic circuit. Such a circuit must contain pipelines, a pump pumping liquid, as well as a cooling place (radiator with airflow). This circuit is usually filled not with water, but with either antifreeze or ethylene glycol.
There are also spindles various capacities, and if low-power ones can be connected directly to the control board, then motors with a power of 1 kW or more must already be connected through the control unit, but this is no longer about us.))
Yes, still often homemade machines install straight grinders or milling cutters with a removable base. Such a decision may be justified, especially when performing work of short duration.
In my case, an air-cooled spindle with a power of 300W was selected.
3. Stepper motors.
The most common engines are of 3 sizes
NEMA17, NEMA23, NEMA 32
they differ in size, power and operating torque
NEMA17 is usually used in 3D printers; they are too small for a milling machine, because... you have to carry a heavy portal, to which additional lateral load is applied during processing.
NEMA32 is unnecessary for such a craft, and besides, you would have to take another control board.
my choice fell on NEMA23 with maximum power for this board - 3A.
People also use steppers from printers, but... I didn’t have them either and still had to buy them and chose everything in the kit.
4. Controller
A control board that receives signals from the computer and transmits voltage to stepper motors that move the axes of the machine.
5. Computer
You need a separate computer (possibly a very old one) and there are probably two reasons for this:
1. It is unlikely that you will decide to place a milling machine next to the place where you are used to reading the Internet, playing with toys, doing accounting, etc. Simply because a milling machine is loud and dusty. Usually the machine is either in a workshop or in a garage (preferably heated). My machine is in the garage; in winter it mostly sits idle, because... no heating.
2. For economic reasons, computers are usually used that are no longer relevant for home life- very used :)
The requirements for the car are basically nothing:
- from Pentium 4
- presence of a discrete video card
- RAM from 512MB
- the presence of an LPT connector (I won’t say anything about USB; I haven’t looked into the new product yet due to the presence of a driver that works via LPT)
such a computer is either taken out of the closet, or, as in my case, bought for next to nothing.
Due to the low power of the machine, we try not to install additional software, i.e. only the axis and control program.
Then there are two options:
- install windows XP (the computer is weak, remember, right?) and the MATCH3 control program (there are others, but this is the most popular)
- install Nixes and Linux CNC (they say that everything is also very good, but I haven’t mastered Nixes)
I’ll add, perhaps, so as not to offend overly wealthy people, that it’s quite possible to install not just a fourth stump, but some kind of i7 - please, if you like it and can afford it.
6. Basic drawing skills, patience, desire and good mood.
Here in a nutshell.
To operate the machine, you need a control program (essentially a text file containing movement coordinates, movement speed and acceleration), which in turn is prepared in a CAM application - usually ArtCam, in this application the model itself is prepared, its dimensions are set, and the cutting tool is selected.
I usually take a slightly longer route, make a drawing, and then save AutoCad *.dxf into ArtCam and prepare the UE there.
Well, let’s begin the process of creating your own.
Before designing a machine, we take several points as starting points:
- The axle shafts will be made from construction studs with M10 threads. Of course, there are undoubtedly more technologically advanced options: a shaft with a trapezoidal thread, a ball screw, but you need to understand that the price of the issue leaves much to be desired, and for a hobby machine the price is absolutely astronomical. However, over time I plan to upgrade and replace the pin with a trapeze.
- Machine body material – 16mm plywood. Why plywood? Available, cheap, cheerful. There are actually a lot of options, some make them from duralumin, others from plexiglass. It's easier for me to use plywood.
Making a 3D model: 
Scan: 
Then I did this, there was no picture left, but I think it will be clear. Printed out the scan on transparent sheets, cut them out and glued them onto a sheet of plywood.
I cut out the parts and drilled the holes. Tools include a jigsaw and a screwdriver.
There is one more little trick that will make life easier in the future: before drilling holes, squeeze all paired parts with a clamp and drill through, so you will get holes equally located on each part. Even if there is a slight deviation during drilling, the internal parts of the connected parts will coincide, and the hole can be drilled out a little.
At the same time, we make specifications and start ordering everything.
what happened to me:
1. The set specified in this review includes: stepper motor control board (driver), NEMA23 stepper motors – 3 pcs., 12V power supply, LPT cord and cooler.
2. Spindle (this is the simplest, but nevertheless it does the job), fasteners and a 12V power supply.
3. Used Pentium 4 computer, most importantly, the motherboard has an LPT and a discrete video card + CRT monitor. I bought it on Avito for 1000 rubles.
4. Steel shaft: f20mm – L=500mm – 2 pcs., f16mm – L=500mm – 2 pcs., f12mm – L=300mm – 2 pcs.
I bought it here, at that time it was more expensive to buy in St. Petersburg. It arrived within 2 weeks.
5. Linear bearings: f20 – 4 pcs., f16 – 4 pcs., f12 – 4 pcs.
20
16
12
6. Mounts for shafts: f20 – 4 pcs., f16 – 4 pcs., f12 – 2 pcs.
20
16
12
7. Caprolon nuts with M10 thread – 3 pcs.
Took along with the shafts on duxe.ru
8. Rotation bearings, closed – 6 pcs.
Same place, but the Chinese have plenty of them too
9. PVA wire 4x2.5
this is offline
10. Screws, dowels, nuts, clamps - a bunch.
This is also offline, in hardware.
11. A set of cutters was also purchased
So, we order, wait, cut and assemble. 
Initially, the driver and power supply for it were installed in the case with the computer together. 
Later, it was decided to place the driver in a separate case; it just appeared. 
Well, the old monitor somehow changed to a more modern one. 
As I said at the beginning, I never thought that I would write a review, so I am attaching photos of the components and will try to give an explanation of the assembly process.
First, we assemble three axles without screws in order to align the shafts as accurately as possible.
We take the front and rear walls of the housing and attach the flanges for the shafts. We string 2 linear bearings on the X-axis and insert them into the flanges. 
We fasten the bottom of the portal to linear bearings, we are trying to roll the base of the portal back and forth. We make sure of the curvature of our hands, take everything apart and drill out the holes a little.
This way we get some freedom of movement of the shafts. Now we attach the flanges, insert the shafts into them and move the base of the portal back and forth to achieve smooth sliding. Tighten the flanges.
At this stage, it is necessary to check the horizontality of the shafts, as well as their coaxiality along the Z axis (in short, so that the distance from the assembly table to the shafts is the same) so as not to overwhelm the future working plane.
We've sorted out the X axis.
We attach the portal posts to the base; I used furniture barrels for this. 
We attach the flanges for the Y axis to the posts, this time from the outside: 
We insert shafts with linear bearings.
Fastening back wall Z axis
We repeat the process of adjusting the parallelism of the shafts and secure the flanges.
We repeat the same process with the Z axis.
We get a rather funny design that can be moved with one hand in three coordinates.
An important point: all axes must move easily, i.e. Having slightly tilted the structure, the portal itself should move freely, without any creaks or resistance.
Next we attach the lead screws.
We cut the M10 construction stud to the required length, screw the caprolon nut approximately in the middle, and 2 M10 nuts on each side. It is convenient to do this by tightening the nuts a little, clamping the stud into the screwdriver and holding the nuts and tightening them.
We insert the bearings into the sockets and push the pins into them from the inside. After this, we fix the studs to the bearing with nuts on each side and tighten them with a second one so that they do not come loose.
We attach the caprolon nut to the base of the axle.
We clamp the end of the pin into a screwdriver and try to move the axle from beginning to end and return it.
A couple more joys await us here:
1. The distance from the nut axis to the base in the center (and most likely at the time of assembly the base will be in the middle) may not coincide with the distance in the extreme positions, because shafts may bend under the weight of the structure. I had to place cardboard along the X axis.
2. The shaft movement may be very tight. If you have ruled out all distortions, then tension may play a role; here you need to catch the moment of tightening the fixation with nuts to the installed bearing.
Having dealt with the problems and having obtained free rotation from start to finish, we move on to installing the remaining screws.
We attach stepper motors to the screws:
In general, when using special screws, be it a trapezoid or a ball screw, the ends are processed on them and then the connection to the engine is very conveniently made with a special coupling. 
But we have a construction pin and had to think about how to fasten it. At that moment I came across a piece of paper gas pipe, and applied it. It “screws” directly onto the stud, onto the engine, it goes into lapping, tightened it with clamps - it holds quite well. 
To secure the engines, I took an aluminum tube and cut it. Adjusted with washers.
To connect the motors I took the following connectors: 
Sorry, I don’t remember what they are called, I hope someone can tell you in the comments.
GX16-4 connector (thanks Jager). I asked a colleague to buy electronics from a store; he just lives nearby, and it was very inconvenient for me to get there. I am very pleased with them: they hold securely, are designed for higher current, and can always be disconnected.
We set up a working field, also known as a sacrificial table.
We connect all the motors to the control board from the review, connect it to a 12V power supply, connect it to the computer with an LPT cable.
Install MACH3 on your PC, make the settings and try it out!
I probably won’t write about the setup separately. This could take a couple more pages.
I'm so happy that I still have a video of the first launch of the machine:
Yes, when in this video there was a movement along the X axis there was a terrible rattling noise, unfortunately, I don’t remember exactly, but in the end I found either a loose washer or something else, in general it was solved without problems.
Next, you need to install the spindle, while ensuring that it is perpendicular (simultaneously in X and Y) to the working plane. The essence of the procedure is this: we attach a pencil to the spindle with electrical tape, thus creating an offset from the axis. As the pencil is lowered smoothly, it begins to draw a circle on the board. If the spindle is full, then the result is not a circle, but an arc. Accordingly, it is necessary to achieve the drawing of a circle by alignment. I have saved a photo from the process, the pencil is out of focus, and the angle is not the same, but I think the essence is clear: 
We find a ready-made model (in my case, the coat of arms of the Russian Federation), prepare the UE, feed it to MACH and off we go!
Machine operation:
Photos in progress:
Well, of course we go through initiation))
The situation is both funny and generally understandable. We dream of building a machine and immediately cutting out something super cool, but in the end we realize that this will take a lot of time.
In a nutshell:
During 2D processing (simply sawing), a contour is specified, which is cut out in several passes.
During 3D processing (here you can plunge into holivar, some argue that this is not 3D but 2.5D, since the workpiece is processed only from above), a complex surface is specified. And the higher the accuracy of the required result, the thinner the cutter is used, the more passes of this cutter are necessary.
To speed up the process, roughing is used. Those. First, the main volume is sampled with a large cutter, then finishing processing is started with a thin cutter.
Next, we try, configure, experiment, etc. The 10,000 hour rule applies here too ;)
Perhaps I won’t bore you any more with stories about construction, adjustment, etc. It’s time to show the results of using the machine - the product. 
As you can see, these are basically sawn contours or 2D processing. For processing volumetric figures It takes a lot of time, the machine is in the garage, and I go there for a short time.
Here they will rightly remark to me - how about... building such a bandura if you can cut out the figure with a U-shaped jigsaw or an electric jigsaw?
It is possible, but this is not our method. As you remember at the beginning of the text, I wrote that it was the idea of making a drawing on a computer and turning this drawing into a product that served as the impetus for the creation of this beast.
Writing a review finally pushed me to upgrade the machine. Those. The upgrade was planned earlier, but “never got around to it.” Last change before this there was the organization of a house for the machine: 
Thus, when the machine is operating in the garage, it has become much quieter and there is much less dust flying around.
The last upgrade was the installation of a new spindle, or rather, now I have two replaceable bases:
1. With Chinese 300W spindle for small work: 
2. With a domestic, but no less Chinese milling cutter “Enkor”... 
With the new milling cutter new possibilities have appeared.
Faster processing, more dust.
Here is the result of using a semicircular groove cutter: 
Well, especially for MYSKU
Simple straight groove cutter: 
Process video:
This is where I will wrap things up, but according to the rules, it would be necessary to sum up the results.
Minuses:
- Expensive.
- For a long time.
- From time to time we have to solve new problems (lights turned off, interference, something went wrong, etc.)
Pros:
- The process of creation itself. This alone justifies the creation of the machine. Finding solutions to emerging problems and implementing them is what, instead of sitting on your butt, you get up and go do something.
- Joy at the moment of giving gifts made with your own hands. Here it should be added that the machine does not do all the work itself :) in addition to milling, it still needs to be processed, sanded, painted, etc.
Thank you very much if you are still reading. I hope that my post, although it won’t encourage you to create such (or another) machine, will somehow broaden your horizons and give you food for thought. I also want to say thank you to those who persuaded me to write this opus; without it, I apparently didn’t even have an upgrade, so everything is a plus.
I apologize for the inaccuracies in wording and all sorts of lyrical digressions. A lot had to be cut, otherwise the text would have turned out simply immense. Clarifications and additions are naturally possible, write in the comments - I will try to answer everyone.
Good luck to you in your endeavors!
Promised links to files:
- drawing of the machine,
- sweep,
format - dxf. This means that you can open the file with any vector editor.
The 3D model is 85-90 percent detailed, many things were done either at the time of preparing the scan, or on site. I ask you to “understand and forgive.”)