Homemade CNC milling machine: do-it-yourself assembly. We build a homemade CNC milling machine Let's start assembling equipment

And so, within the framework of this article-instruction, I want you, together with the author of the project, a 21-year-old mechanic and designer, to make your own. The narration will be conducted in the first person, but know that, to my great regret, I am not sharing my experience, but only freely retelling the author of this project.

There will be a lot of drawings in this article, the notes to them are made in English, but I am sure that a real techie will understand everything without further ado. For ease of understanding, I will break the story into "steps".

Foreword from the author

Already at the age of 12, I dreamed of building a machine that would be able to create various things. A machine that will give me the ability to make any household item. Two years later, I came across the phrase CNC or more precisely, to the phrase "CNC milling machine". After I found out that there are people who can make such a machine on their own for their own needs, in their own garage, I realized that I could do it too. I must do it! For three months, I tried to collect the right parts, but did not budge. So my obsession gradually faded away.

In August 2013, the idea of building a CNC milling machine re-engaged me. I had just completed my bachelor's degree from the University of Industrial Design, so I was quite confident in my abilities. Now I clearly understood the difference between me today and me five years ago. I learned how to work with metal, mastered the techniques of working on manual metalworking machines, but most importantly, I learned how to use development tools. I hope this tutorial will inspire you to create your own CNC machine!

Step 1: Design and CAD Model

It all starts with thoughtful design. I made several sketches to get a better feel for the size and shape of the future machine. After that I created a CAD model using SolidWorks. After I modeled all the parts and assemblies of the machine, I prepared technical drawings. I used these drawings for the manufacture of parts on manual metalworking machines: and.

To be honest, I love good handy tools. That is why I have tried to make the maintenance and adjustment of the machine as easy as possible. I placed the bearings in special blocks in order to be able to quickly replace. The guides are serviceable so my car will always be clean when the job is done.

Downloads "Step 1"

dimensions

Step 2: Bed

The bed provides the machine with the necessary rigidity. It will be equipped with a movable portal, stepper motors, Z-axis and spindle, and later the work surface. I used two 40x80mm Maytec aluminum profiles and two 10mm thick aluminum end plates to create the base frame. I connected all the elements to each other on aluminum corners. To strengthen the structure inside the main frame, I made an additional square frame from profiles of a smaller section.

In order to avoid dust on the rails in the future, I installed aluminum protective corners. The angle is mounted using T-nuts, which are installed in one of the grooves of the profile.

Both end plates are fitted with bearing blocks for mounting the drive screw.

Carrier frame assembly

Corners to protect the rails

Downloads "Step 2"

Drawings of the main elements of the bed

Step 3: Portal

The movable portal is the executive body of your machine, it moves along the X axis and carries the milling spindle and the Z axis support. The higher the portal, the thicker the workpiece that you can process. However, a high gantry is less resistant to the loads that occur during processing. The high side posts of the portal act as levers relative to the linear rolling bearings.

The main task that I planned to solve on my CNC milling machine was the processing of aluminum parts. Since the maximum thickness of aluminum blanks suitable for me is 60 mm, I decided to make the portal clearance (the distance from the working surface to the upper cross beam) equal to 125 mm. In SolidWorks, I converted all my measurements into a model and technical drawings. Due to the complexity of the parts, I processed them on an industrial CNC machining center, which additionally allowed me to process chamfers, which would be very difficult to do on a manual metal milling machine.

Downloads "Step 3"

Step 4: Z Axis Caliper

In the Z axis design, I used a front panel that attaches to the Y axis movement bearings, two plates to reinforce the assembly, a plate to mount the stepper motor, and a panel to mount the milling spindle. On the front panel, I installed two profile guides along which the spindle will move along the Z axis. Please note that the Z axis screw does not have a counter support at the bottom.

Downloads "Step 4"

Step 5: Guides

Guides provide the ability to move in all directions, ensure smooth and precise movements. Any play in one of the directions can cause inaccuracies in the processing of your products. I chose the most expensive option - profiled hardened steel rails. This will allow the structure to withstand high loads and provide the positioning accuracy I need. To ensure the guides are parallel, I used a special indicator during their installation. The maximum deviation relative to each other was no more than 0.01 mm.

Step 6: Screws and Pulleys

Screws convert rotational motion from stepper motors into linear motion. When designing your machine, you can choose from several options for this assembly: A screw-nut pair or a ball screw pair (ball screw). The screw nut, as a rule, is subjected to more frictional forces during operation, and is also less accurate relative to the ball screw. If you need increased accuracy, then you definitely need to opt for a ball screw. But you should know that ball screws are quite expensive.

Despite the fact that the concept of convenient and beautiful addresses for site pages was introduced a long time ago, not all site owners use them yet, and recommendations for using CNC are often not complete. This article details the issues of choosing the right NC structure, describes the most common mistakes when using these friendly addresses, and also answers some other popular questions.

What is CNC

CNC is an abbreviation for the phrase “ H human P onyatnye At RLs” (in English, S earch E ngine F riendly URLs), which means beautiful and friendly addresses. The meanings attached to the Russian and English terms are slightly different, since CNC concerns more about usability (human-friendliness of use), and SEF more focused on SEO (be search engine friendly). Be that as it may, CNC addresses have many advantages over regular addresses, therefore, they are always recommended to be used, but used wisely, like any other tool.

Let's consider an example of CNC

Old versions of addresses (inconvenient and unfriendly):

3. CNC length

Long NCs are not very usability friendly: they are hard to remember, they are often cut off when pasting a link in old forums and often in social networks (and also in search results if breadcrumbs are not defined), they also make it difficult to navigate the site.

An example of a long and awkward CNC:

Set up your CMS in such a way that the length of the CNC is no more than 60-80 characters (the smaller, the better and more convenient). If your product subcategories (for example, in an online store) have 4-5 levels of nesting, then it is advisable to display in the CNC only the last subcategory or the first and last, but not all 4-5, in order to reduce the length of the CNC.

4. Underscores or hyphens?

Which is better for CNC to separate words: underscores or hyphens? Both are possible, but hyphens are preferable, since they require one press on the keyboard to type them, and two (plus Shift) for underlining.

What about spaces? It is better not to use spaces in CNC, as in many cases they can only cause a headache for the webmaster. Replace spaces with other separator characters (hyphens, underscores, or, in extreme cases, plus signs). Optimal CNCs contain the same type of characters in any language and separators - no spaces, quotes, commas or other service characters.

5. Which CNC to choose for multilingual sites?

When adding additional language versions of the site, you must first decide whether you want to put them on a subdomain, a separate domain, or still add them to the CNC? If the latter option, then it is best to add the part responsible for the language version to the beginning of the address (immediately after the domain name).

6. Do I need CNC for image and video titles?

If you plan to receive traffic to the site also from searching for images or videos, then only the name of the image is important here (for example, hrizantema.jpg instead of 1244_2344.jpg), and the path itself, where the image or video file is stored, does not matter (only Google can find images by folder name). Also, image addresses are not as actively used as page addresses.

Common mistakes when using the CNC

Use of spaces and service characters.

Formation of too long NC addresses.

Using Numeric Values in the CNC

It is difficult to call such addresses CNC, since they only make it clear that we will go to the news section, but the ID numbers do not mean anything.

Lack of pages on the site when removing the right parts of the CNC before the slashes.

Use of non-meaningful words in the address

/page/contact.html
/category/news/some-news-title.html

The /page/ particle in this case (or /category/) is not significant, so it can be removed to shorten the length of the NC.

Conclusion

Frequently occurring problems with the CNC are mainly related to the use of old CMS. In new content management systems, this module is more or less well thought out and allows you to flexibly manage the CNC structure (although sometimes you have to add auxiliary plugins). If you are using old versions of CMS and want to have beautiful CNCs on your site, you should consider switching to new systems, choosing them depending on the type of project.

And what rules do you follow when thinking over CNC addresses?

Knowing that it is a complex technical and electronic device, many craftsmen think that it is simply impossible to make it with their own hands. However, this opinion is erroneous: you can make such equipment yourself, but for this you need to have not only its detailed drawing, but also a set of necessary tools and relevant components.

Processing of duralumin blanks on a homemade desktop milling machine

When deciding to make a homemade CNC machine, keep in mind that this can take a significant amount of time. In addition, certain financial costs will be required. However, not being afraid of such difficulties and having the right approach to solving all issues, you can become the owner of affordable, efficient and productive equipment that allows you to process workpieces from various materials with a high degree of accuracy.

To make a 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 that fully meets all your requirements with your own hands.

Instructions for assembling a homemade CNC milling machine

Below in the photo you can see a self-made one, which is accompanied by detailed instructions for manufacturing and assembly, indicating the materials and components used, exact “patterns” of machine parts and approximate costs. The only negative is the instruction in English, but it is quite possible to understand the detailed drawings even without knowing the language.

Download free instructions for the manufacture of 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 Final assembly stage

Preparatory work

If you decide that you will design a CNC machine with your own hands without using a ready-made kit, then the first thing you will need to do is to opt for a concept diagram according to which such mini-equipment will work.

The basis of CNC milling equipment can be taken from an old drilling machine, in which the working head with a drill is replaced with a milling head. The most complex thing that will have to be designed in such equipment is a mechanism that ensures the movement of the tool in three independent planes. This mechanism can be assembled on the basis of 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 such a concept. However, its main drawback is that only workpieces made of plastic, wood and thin sheet metal can be processed on such a CNC machine. 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 from various materials, a sufficiently powerful stepper motor must be responsible for moving the working tool. It is not at all necessary to look for a stepper-type engine, it can be made from a conventional electric motor, subjecting the latter to a slight refinement.

The use of a stepper motor in yours will make it possible to avoid the use of a screw gear, and the functionality and characteristics of home-made equipment will not become worse from this. If you still decide to use carriages from the printer for your mini-machine, then it is advisable to pick them up 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 manufacture that needs 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 home-made CNC milling equipment can be a rectangular beam, which must be securely fixed on the rails.

The supporting structure of the machine must have high rigidity, it is better not to use welded joints during its installation, and all elements must be connected only with screws.

This requirement is explained by the fact that the welds are very poorly tolerated by vibration loads, which the supporting structure of the equipment will necessarily be subjected to. Such loads will eventually lead to the fact that the frame of the machine will begin to collapse over time, and changes in geometric dimensions will occur in it, which will affect the accuracy of the equipment settings and its performance.

Welds during the installation of the frame of a homemade milling machine often provoke the development of play in its nodes, as well as the deflection of the guides, which occurs under severe loads.

In the milling machine, which you will assemble with your own hands, a mechanism must be provided to ensure the movement of the working tool in a 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 detail of the milling machine is its vertical axis, which for a homemade device can be made from an 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 you can make the vertical axis of the machine with your own hands, casting it from aluminum according to the dimensions indicated in the finished drawing.

After all the components of your homemade milling machine are prepared, you can begin to assemble it. This process begins with 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 the milling head in the horizontal plane, and the second - for moving the head, respectively, in the vertical plane. After that, the remaining components and assemblies of home-made equipment are mounted.

Rotation to all components of home-made CNC equipment should be transmitted only through belt drives. Before connecting a program control system to the assembled machine, you should check its performance in manual mode and immediately eliminate all identified shortcomings in its operation.

You can watch the assembly process on the video, which is easy to find on the Internet.

Stepper motors

In the design of any CNC milling machine, there are necessarily stepper motors that provide tool movement 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 printers were equipped with electric motors with fairly high power. In addition to stepper motors from an old printer, it is worth taking strong steel rods, which can also be used in the construction of your homemade machine.

To make a CNC router with your own hands, you will need three stepper motors. Since there are only two of them in a dot matrix printer, it will be necessary to find and disassemble another old printing device.

It will be a big plus if the engines 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 found: how many degrees it rotates in one step, what is the supply voltage, and also 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 must first be selected according to the drawing of your equipment. To fix the motor shaft and to attach it to the stud, it is convenient to use a thick rubber winding from an electric cable. Elements 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 filling of equipment

Your do-it-yourself CNC machine will be controlled by software, and you need to choose the right one. When choosing such software (you can write it yourself), it is important to pay attention to the fact that it is efficient and allows the machine to implement all its functionality. Such software should contain drivers for controllers that will be installed on your mini milling machine.

In a homemade CNC machine, the LPT port is mandatory, through which the electronic control system is connected to the machine. It is very important that this connection is made through the installed stepper motors.

When choosing electronic components for your do-it-yourself 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 the electronic components of the CNC system, you need to download the necessary software and drivers. Only after that, a test run of the machine follows, checking the correct operation of the machine under the control of downloaded programs, identifying shortcomings and promptly eliminating them.

In preparation for the design of the technological process, a detailed analysis of the drawing is carried out to identify the missing dimensions and structural and technological data. Missing dimensions and other data can be obtained from the designer, from assembly drawings, or by geometric constructions of the part outline.

In order to facilitate the preparation of NC, dimensioning in the part drawing must satisfy the requirements of programming.

Since processing on CNC machines is carried out according to commands that determine the coordinates of the trajectory points in a rectangular coordinate system, the dimensions in the drawings must also be specified in a rectangular coordinate system from the unified design bases of the part. To do this, you must select the origin of coordinates and the direction of the axes. It is desirable that the direction of the axes of the relative coordinate system of the part coincide after its installation on the machine with the direction of the coordinate axes of the machine.

When applying dimensions on drawings, in some cases, holes, groups of holes or part elements can be specified in the local coordinate system, as shown for hole B (Fig. 11.8, a). The transition from such a system with the beginning at point A to the main system does not cause difficulties.

Mounting holes located at one or another radius from the center of the main hole are usually set by the central angle of the arc between their axes and radii. For CNC machines, such information should be replaced by the coordinates of the axes of each hole (Fig. 11.8, b). In the example under consideration, it is advisable to assign the axis of the large hole as the origin of coordinates, since it provides a minimum length of idle (positioning) moves during processing.

Rice. 11.8. Dimensioning on the drawings of parts for CNC machines:

a) in the local coordinate system; b) in the coordinate system of the main hole

Parts often have a large number of small mounting holes. Specifying the coordinates of the axis of each of them is impractical, because this makes the drawing difficult to read. In such cases, to indicate the dimensions, it is rational to use the tabular method, which is also convenient for programming (Fig. 11.9, a).

When processing curved contours of flat parts on a CNC machine, it is necessary to indicate in the drawing the dimensions of the radii of the arcs, the coordinates of the centers of the radii and the coordinates of the junction points of the arcs (Fig. 11.9, b).

Rice. 11.9. Dimensioning on detail drawings using the tabular method:

a) axes of mounting holes; b) curvilinear contours

According to the general rule for applying dimensions on the drawings of parts machined on lathes, sections with tight tolerances (dimensions a 1, a 2, a 3 in Fig. 11.10, a) and intermediate sections with wide tolerances (dimensions in 1, in 2 , in 3 , in 4). This is quite justified for machines with manual control, because. the worker only needs to maintain exactly these dimensions. For a CNC machine, this does not matter, because the accuracy of the displacements is the same, and the origin, as a rule, does not coincide with the design base and is outside the part. Therefore, dimensions for such parts should be applied in a chain (Fig. 11.10, b).

Rice. 11.10. Dimensioning on drawings of parts for turning:

a) on machines with manual control; b) on CNC machines

In general, the application of dimensions on the drawings of parts processed on CNC machines should be such that when preparing the control program there is no need to recalculate them.

So, you have decided to build a homemade CNC milling machine, or maybe you are just thinking about it and don't know where to start? There are many advantages to having a CNC machine. Home machines can mill and cut almost all materials. Whether you're an amateur or a craftsman, this opens up great possibilities for creativity. The fact that one of the machines might end up in your workshop is even more enticing.

There are many reasons why people want to build their own CNC router. As a rule, this is 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 big. Or you can be like me and have a lot of fun doing your own work and creating something unique. You can just do it to gain experience in mechanical engineering.

Personal experience

When I first started designing, thinking about and making my first DIY CNC Router, it took about a day to complete the project. Then, when I started buying parts, I did a little research. And I found some information in various sources and forums, which led to new questions:

Do I really need ball screws, or will regular studs and nuts work just fine?
What is the best linear bearing and can I afford one?
With what parameters do I need a motor, and is it better to use a stepper or a servo?
Does the body material deform too much with a large machine size?
And so on.

Fortunately, I was able to answer some of the questions thanks to my engineering and technical base left after my studies. However, many of the problems I would run into could not be calculated. I just needed someone with hands-on experience and information on the subject.

Of course, I received many answers to my questions from different people, many of which contradicted each other. Then I had to continue researching to find out which answers are worthwhile and which are rubbish.

Every time I had a question that I didn't know the answer to, I had to repeat the same process. For the most part, this is due to the fact that I had a limited budget and wanted to take the best of what my money can buy. The same situation is with many people who create a homemade CNC milling machine.

Do-it-yourself kits and kits for assembling CNC routers

Yes, there are kits available for manual assembly, but I haven't seen one yet that can be customized for specific needs.

It is also not possible to make changes to the design and type of the machine, and 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 bad, then the final machine will be bad.

That's why you need to be aware of what you're building and understand the role every detail plays!

Management

This guide aims to prevent you from making the same mistakes that I wasted my precious time and money on.

We will go over all the components down to the bolts, looking at the advantages and disadvantages of each type of each part. I will cover every aspect of design and show you how to build a DIY CNC router. I will take you through the mechanics to the software and everything in between.

Keep in mind that do-it-yourself CNC machine drawings offer few ways to solve some problems. This often results in "sloppy" design or unsatisfactory machine performance. That's why I suggest you read this guide first.

LET'S START

STEP 1: Key design decisions

The following questions need to be considered first:

Determination of a suitable design specifically for you (for example, if you make a woodworking machine with your own hands).
Required processing area.
Availability of the workspace.
Materials.
Tolerances.
Design methods.
Available tools.
Budget.