DIY machine for milling printed circuit boards. CNC milling of printed circuit board
As I remember now, on February 23rd I came across a post on there, where a person wanted to engrave printed circuit boards on a 3D printer. In the comments they advised not to torment the printer's belly and pay attention to the Cyclone PCB Factory project.
I got excited about the idea. Later, at some point I will even regret that I took it, but that will be much later.
About our own CNC router for printed circuit boards I dreamed of it for a very long time, this was the second thing I wanted after a 3D printer. I decided to repeat the project, especially since I already had something in my bins.
I downloaded the project files and without hesitation began printing the parts. Got it done in about a week. I printed everything except the Z axis.
There are no detailed photographs of all the details left. Someone took a screenshot of the print settings and the result. Nozzle 0.4, layer height 0.24. I also printed with a layer of 0.28 - it prints quite normally.
I wanted to make the machine colored, so I printed various parts with plastic different color. Plastic used ABS Prostoplast. Colors of space, grassy green, reddening sunset.
It would be better if I printed everything in gray space. Red and green turned out to be quite fragile and some of the parts cracked during assembly. Some were cured with acetone, some were reprinted.
Accessories:
I had three free stepper motors, bought them for a 3D printer project, and decided to use them temporarily.
I got 8mm guides from inkjet printers, having torn apart several printers into parts. I wooled local thrift stores, Avito. The donors were HP inkjet printers at 100-200 rubles apiece. The long guide was sawn into two parts, on the X and Z axes.
The paper clamp from which I removed the rubber rollers went to the Y axis. The length was just enough to cut along the knurling.
The linear bearings were left over from the 3D printer; I converted the printer to bronze bushings with polka dots.
For electronics I decided to use one of my Arduino Uno on atmega328p. I bought an additional cnc shield 3.0 board for Arduino on Ali for 200 and a few kopecks rubles.
Power supply 12V from Leroy Merlin. I bought it to power three 12V halogens, but it didn’t work. I had to repair the transformer for the Tachibra halogen lamps, and this power supply took root on the machine.
I installed 8825 drivers for the 3D printer, but I still have a4988 from the printer. I put them on the machine.
I ordered 608ZZ bearings from Ali, a dozen for 200 and a few kopecks rubles..
I planned to use my Chinese GoldTool engraver as a spindle.
I got the M8 threaded rods from work for free, they were left over from some installation. I almost picked it up from the trash heap.
While the project was being printed and the parts were on their way from Ali, I asked a furniture maker friend to cut out a base and a table from MDF. He was not lazy and did not spare the scraps; he cut out 2 bases and 2 tables. The photo shows one of the sets.
I didn’t have any plywood in my bins; a greedy animal wouldn’t allow me to buy a sheet of plywood. By the way, MDF fit very well.
I started assembling the machine. Everything would be fine, but the standard 13 nuts fell through and dangled inside the gear, and the 14 nuts did not fit into the gears. I had to melt the 14th nut into the gears with a soldering iron.
The gears either dangled on the axes of the stepper motor or did not fit.
The nuts of the M3 screws were turned in the mounting sockets.
I found several square nuts for M3 threads (I once disassembled some kind of plug made from it), which fit perfectly and did not turn. At work I also found some plugs like this and used them on the nuts. These are mainly guide mounts. Regular nuts for M3 threads had to be held with a thin screwdriver blade to prevent them from turning.
Somehow I collected it. Later, while reading topics about Cyclone, I came across recycled machine parts for metric fasteners. From this set I re-printed the gears and the Z-axis limit switch mount. It’s a pity I didn’t come across this set of spare parts earlier. I would print these parts.
Hoping to use his Chinese engraver, I first printed one Dremel mount from the kit, then the second. It didn’t fit, my engraver didn’t fit into any of them. The original Dremel, the simplest one, cost just over three thousand rubles. For what???
Extra spare parts.
And yet, the linear bearings were dangling in their sockets like something in an ice hole.
I had to order a 200W spindle with an ER11 collet clamp for a little over a thousand. I was lucky to get a discount and use the coupon.
While the spindle was moving, I printed out a mount for it from the machine kit. And again there is a puncture, it is just as defective. And not a word about the spindle clamp.
As a result, I found and printed this mount for a 52mm spindle. After a little modification, the mount fit on the machine, the spindle fit into it well.
But the bearings on the Cargo bushings had to be removed from them. I installed Chinese LM8UU
I would also like to say something about the Chinese 608zz bearings. New bearings with play. Terrible. One thing is that they are relatively inexpensive. I didn't look for bearings from us.
By the way, the bearings fit into the seats just like something in a hole. IN seats the bearings were loose. I don't know if this is a bug or a feature. As a result, I applied electrical tape to the bearing races.
The Chinese lm8uu and lm8luu from a 3D printer also turned out to be rubbish. As a result, I made sliding bearings for the Y axis on Cargo 141091 bushings. I printed out a plastic cage and inserted a pair of bushings into it. The resulting bearings were inserted into the mounts.
For the Z axis I chose more or less lively lm8uu. On the X-axis, I installed the upper bearing lm8uu, and instead of the two lower ones, I printed a plastic cage to the size of lm8luu and inserted a pair of Cargo bushings into it.
Luckily, I bought them at one time. They came in handy.
While assembling the machine, I regretted taking it on. But there was nowhere to go, the project had to be completed. Collected. Launched!
Some more photos of the assembly process.
The very beginning of the assembly...
Drivers for the stepper, the dude elegantly made everything without using a microcontroller. I read this, looked at my drill for circuit boards with a tight manual feed, and decided to attach an up-down feed control to it. I bought a driver for a stepper, a suitable stepper from a printer was pulled out of the bins, an expensive one was bought, which I mounted on the motor shaft from some printer, then the driver arrived and the movement began.
Here is the first version of my plate drill:
People with an engineering mindset will immediately notice the addictive position of the lever relative to the guides (six hundred rubles for a brass tube, and the same amount for a brass rod! It would be better if I bought linear bearings and two guides in China), because of this decision, the spindle moves unevenly, jerkily , and you can break a certain number of drills if they are made of carbide. And it was for their sake that everything was started.
While I was waiting for the hardware, I turned on a powerful backlight for this machine 
The device says that it is VERY BRIGHT. But it’s comfortable to work with, I decided not to adjust the backlight
here is a photo at work
I started sawing the U-axis drive. I decided to just add some pieces of wood to the existing structure 
Note the nanotech connection between the shaft and the lead screw
To do this, I bought a brake light sensor from some kind of VAZ, and mercilessly broke it down so that only a brass tube remained 
Now it's the turn of electronics.
I played around in Proteus and on a breadboard with the circuit and code, and etched a board for the future controller 
The Arduino nano will act as the brains of the machine, because I can’t code for anything more serious. Control by potentiometer and encoder with button.
The driver itself is called EASY DRIVER on the Internet, which seems to indicate the ease of working with it. It's right. It needs two signals - STEP and DIR. We move first with the engine, the second we tell which direction to step. After trying a crude library for it, I decided to write everything myself, and it turned out well in the end.
It's all powered by a 19-volt laptop power supply. The driver can pass up to 30 volts through itself, and the motor with the cartridge is designed for 24, if I’m not mistaken, its speed is still not enough.
Video of the first test:
The encoder can be used to move the spindle up and down along the Y axis, the variable resistor sets the distance by which the spindle will move with one click of the encoder, and also sets the feed speed when the “DRILL!” button is pressed. It turned out to be very convenient to use a pre-prepared hole-making algorithm. I also attached a display that was lying around for show off. Did you connect it using this? to save arduino legs
I screwed all the boards and handles into place, and this is what happened:
look
After struggling with the code I got it all to work as I needed, and here is the finished device.
Now all that remains is to come up with a new crazy project to test your product in combat conditions, as well as attach a pedal to free your hands.
If anyone is interested in anything in the review, ask, PM, comments, whatever
The question of how to make a CNC machine can be answered briefly. Knowing that a homemade CNC milling machine, in general, is a complex device with a complex structure, it is advisable for the designer to:
- acquire drawings;
- purchase reliable components and fasteners;
- prepare a good tool;
- have a lathe on hand and drilling machines CNC machined to produce quickly.
It wouldn’t hurt to watch the video – a kind of instructional guide on where to start. I’ll start with preparation, buy everything I need, figure out the drawing - here correct solution novice designer. That's why preparatory stage, preceding assembly, is very important.
Preparatory stage work
To make a homemade CNC milling machine, there are two options:
- You take a ready-made running set of parts (specially selected components), from which we assemble the equipment yourself.
- Find (make) all the components and start assembling a CNC machine with your own hands that would meet all the requirements.
It is important to decide on the purpose, size and design (how to do without a drawing homemade machine CNC), find diagrams for its manufacture, purchase or manufacture some parts that are needed for this, acquire lead screws.
If you decide to create a CNC machine with your own hands and do without ready-made sets of components and mechanisms, fasteners, you need a diagram assembled according to which the machine will work.
Usually, having found schematic diagram devices, they first model all the machine parts, prepare technical drawings, and then use them to produce components from plywood or aluminum on lathes and milling machines (sometimes it is necessary to use a drilling machine). Most often, working surfaces (also called a work table) are plywood with a thickness of 18 mm.
Assembly of some important machine components
In the machine that you started assembling with your own hands, you need to provide a number of critical components that ensure vertical movement of the working tool. In this list:
- helical gear – rotation is transmitted using a toothed belt. It is good because the pulleys do not slip, evenly transferring forces to the shaft of the milling equipment;
- if you use a stepper motor (SM) for a mini-machine, it is advisable to take a carriage from a larger printer model - more powerful; old dot matrix printers had fairly powerful electric motors;
- for a three-coordinate device, you will need three SDs. It’s good if there are 5 control wires in each, the functionality of the mini-machine will increase. It is worth assessing the magnitude of the parameters: supply voltage, winding resistance and motor rotation angle in one step. To connect each stepper motor you need a separate controller;
- with the help of screws, the rotational movement from the motor is converted into linear. For achievement high precision, many people consider it necessary to have ball screws (ball screws), but this component is not cheap. When selecting a set of nuts and mounting screws for mounting blocks, choose them with plastic inserts, this reduces friction and eliminates backlash;
- instead of a stepper motor, you can take a regular electric motor, after a little modification;
- a vertical axis that allows the tool to move in 3D, covering the entire X-ray table. It is made from aluminum plate. It is important that the dimensions of the axis are adjusted to the dimensions of the device. If you have a muffle furnace, the axle can be cast according to the dimensions of the drawings.
Below is a drawing made in three projections: side view, rear view, and top view.
Maximum attention to the bed
The necessary rigidity of the machine is provided by the bed. A movable portal, a system of rail guides, a stepper motor, work surface, Z axis and spindle.
For example, one of the creators of a homemade CNC machine made the supporting frame from aluminum profile Maytec - two parts (section 40x80 mm) and two end plates 10 mm thick from the same material, connecting the elements with aluminum corners. The structure is reinforced; inside the frame there is a frame made of smaller profiles in the shape of a square.
The frame is mounted without the use of welded joints (welded seams are poorly able to withstand vibration loads). It is better to use T-nuts as fastenings. The end plates are provided with a bearing block for mounting lead screw. You will need a plain bearing and a spindle bearing.
The craftsman determined that the main task of the self-made CNC machine was the production of aluminum parts. Since workpieces with a maximum thickness of 60 mm were suitable for him, he made the portal clearance 125 mm (this is the distance from the upper cross beam to the working surface).
This difficult installation process
It is better to assemble homemade CNC machines, after preparing the components, strictly according to the drawing so that they work. The assembly process using lead screws should be performed in the following sequence:
- a knowledgeable craftsman begins by attaching the first two motors to the body - behind the vertical axis of the equipment. One is responsible for the horizontal movement of the milling head (rail guides), and the second is responsible for movement in the vertical plane;
- a movable portal moving along the X axis carries the milling spindle and support (z axis). The higher the portal is, the larger the workpiece can be processed. But at a high portal, during processing, the resistance to emerging loads decreases;
- For fastening the Z-axis motor and linear guides, front, rear, upper, middle and lower plates are used. Make a cradle for the milling spindle there;
- The drive is assembled from carefully selected nuts and studs. To fix the motor shaft and attach it to the stud, use a rubber winding of a thick electric cable. The fixation may be screws inserted into a nylon sleeve.
Then the assembly of the remaining components and assemblies of the homemade product begins.
We install the electronic filling of the machine
To make a CNC machine with your own hands and control it, you need to operate with a correctly selected numerical program controlled, high-quality printed circuit boards and electronic components (especially if they are Chinese), which will allow you to implement everything on a CNC machine functionality, processing a part of complex configuration.
In order to avoid problems in control, homemade CNC machines have the following components among the components:
- stepper motors, some stopped for example Nema;
- LPT port through which the CNC control unit can be connected to the machine;
- drivers for controllers, they are installed on a mini-milling machine, connecting in accordance with the diagram;
- switching boards (controllers);
- 36V power supply unit with a step-down transformer that converts to 5V to power the control circuit;
- laptop or PC;
- button responsible for emergency stop.
Only after this, CNC machines are tested (in this case, the craftsman will make a test run of it, loading all the programs), and existing shortcomings are identified and eliminated.
Instead of a conclusion
As you can see, it is possible to make a CNC that is not inferior to Chinese models. Having made a set of spare parts with the right size, having high-quality bearings and enough fasteners for assembly, this task is within the power of those who are interested in software technology. You won’t have to look for an example for long.
The photo below shows some examples of numerically controlled machines, which were made by the same craftsmen, not professionals. Not a single detail was done hastily, arbitrary size, and fits to the block with great precision, with careful alignment of the axes, the use of high-quality lead screws and reliable bearings. The statement is true: as you assemble, so will you work.
A duralumin blank is processed using CNC. With such a machine, which was assembled by a craftsman, you can perform a lot of milling work.
Another sample assembled machine, where a fiberboard board is used as a work table on which a printed circuit board can be manufactured.
Anyone who starts making the first device will soon move on to other machines. Perhaps he will want to test himself as an assembler of a drilling unit and, unnoticed, will join the army of craftsmen who have assembled quite a few homemade devices. Technical creativity will make people's lives interesting, varied and rich.
Nowadays, handicraft people can increasingly find new machines that are controlled not by hands, as we are all accustomed to, but by computer software and computerized equipment. This innovation is called CNC (computer numerical control).
This technology is used in many institutions, large industries, as well as in private workshops. Automated system control allows you to save a lot of time, as well as improve the quality of the products produced.
The automated system is controlled by a computer program. This system includes asynchronous motors with vector control, having three axes of movement of the electric engraver: X, Z, Y. Below we will look at what machines with automatic control and calculations.
Typically, all CNC machines use electric engraver, or a router on which you can change attachments. A numerically controlled machine is used to add decorative elements to certain materials and more. CNC machines, due to advances in the computer world, must have many functions. These functions include:
Milling
A mechanical process of processing a material, during which a cutting element (an attachment in the form of a milling cutter) produces rotational movements on the surface of the workpiece.
Engraving
It consists of applying one or another image to the surface of the workpiece. To do this, use either cutters or a graver (a steel rod with one end pointed at an angle).
Drilling
Mechanical processing of material by cutting, using a drill, which creates holes different diameters and holes having many faces of different sections and depths.
Laser cutting
A method of cutting and cutting material in which there is no mechanical impact, the high accuracy of the workpiece is maintained, and the deformations made by this method have minimal deformations.
Plotter
High-precision drawing of complex diagrams, drawings, geographical maps. Drawing is done by writing block, using a specialized pen.
PCB drawing and drilling
Manufacturing of circuit boards, as well as drawing electrically conductive circuits on the surface of a dielectric plate. Also drilling small holes for radio components.
What functions your future computer-controlled machine will perform is up to you to decide. Next, let’s look at the design of a CNC machine.
Type of CNC machines
Technological features and capabilities of these machines are equivalent to universal machines. However, in modern world, there are three types of CNC machines:
Turning
The purpose of such machines is to create parts based on the type of bodies of rotation, which consists of processing the surface of the workpiece. Also production of internal and external threads.
Milling
The automated operation of these machines consists of processing the planes and spaces of various body blanks. They carry out flat, contour and stepped milling, at various angles, as well as from several sides. They drill holes, cut threads, ream and boring workpieces.
Drilling - boring
They perform reaming, hole drilling, boring and reaming, countersinking, milling, threading and much more.
As we can see, CNC machines have a wide range of functionality that they perform. Therefore, they are equated to universal machines. All of them are very expensive and it is simply impossible to buy any of the above installations due to financial insufficiency. And you might think that you will have to perform all these actions manually throughout your life.
You don't have to be upset. Skillful hands countries, from the first appearance of factory CNC machines, began to create home-made prototypes that work no worse than professional ones.
All components for CNC machines can be ordered on the Internet, where they are freely available and are quite inexpensive. By the way, the body of an automated machine can be made with your own hands, and correct sizes you can go online.
Tip: Before choosing a CNC machine, decide what material you will be processing. This choice will be of major importance when constructing the machine, since it directly depends on the size of the equipment, as well as its costs.
The design of the CNC machine depends entirely on your choice. You can purchase a ready-made standard set of all the necessary parts and simply assemble it in your garage or workshop. Or order all equipment separately.
Consider a standard set of parts on the picture:
- The immediate working area, which is made of plywood, is the tabletop and side frame.
- Guide elements.
- Guide holders.
- Linear bearings and sliding bushings.
- Support bearings.
- Lead screws.
- Stepper motor controller.
- Controller power supply.
- Electric engraver or router.
- A coupling connecting the lead screw shaft to the shaft of stepper motors.
- Stepper motors.
- Running nut.
Using this list of parts, you can safely create your own CNC wood milling machine with automated operation. Once you have assembled the entire structure, you can safely begin work.
Principle of operation
Perhaps the most important element on this machine is the milling cutter, engraver or spindle. It depends on your choice. If you have a spindle, then the tail of the cutter, which has a collet for fastening, will be tightly attached to the collet chuck.
The chuck itself is directly mounted on the spindle shaft. The cutting part of the cutter is selected based on the selected material. An electric motor, which is located on a moving carriage, rotates the spindle with a cutter, which allows processing the surface of the material. Stepper motors are controlled by a controller, to which commands are sent from computer program.
Electronics The machine works directly on the provision of computer software, which must be supplied with the ordered electronics. The program transmits commands in the form of G codes to the controller. Thus, these codes are stored in the controller’s RAM.
After selecting a processing program on the machine (finishing, roughing, three-dimensional), commands are distributed to stepper motors, after which the surface of the material is processed.
Advice: Before starting work, you need to test the machine using a specialized program and run a test part to make sure the CNC is working correctly.
Assembly
Machine assembly with your own hands It won't take you too much time. Moreover, on the Internet now you can download a lot of different schemes and drawings. If you bought a set of parts for a homemade machine, then its assembly will be very quick.
So, let's look at one of them drawings the actual hand machine.
Drawing of a homemade CNC machine.
As a rule, the first step is to make a frame from plywood, 10-11 millimeters thick. The tabletop, side walls and movable portal for installing a router or spindle are made only from plywood material. The tabletop is made movable, furniture guides of appropriate sizes are used.
The end result should be a frame like this. After frame construction ready, a drill and special bits come into play, with which you can make holes in the plywood.
Frame of the future CNC machine.
In the finished frame, it is necessary to prepare all the holes in order to install bearings and guide bolts in them. After this installation, you can install all fastening elements, electrical installations etc.
After the assembly is completed, important stage becomes setting software machine and computer program. When setting up the program, the operation of the machine is checked for the correctness of the specified dimensions. If everything is ready, you can begin the long-awaited work.
Tip: Before starting work, you need to check the correct fastening of the workpiece material and the reliability of fastening working attachment. Also make sure that the selected material matches the machine being manufactured.
Equipment setup
The CNC machine is set up directly from the working computer on which the program for working with the machine is installed. It is in the program that they are loaded necessary drawings, graphs, drawings. Which are converted in sequence by the program into G codes necessary to control the machine.
When everything is loaded, trial actions are performed regarding the selected material. It is during these actions that all necessary preset dimensions are checked.
Advice: Only after a thorough check of the machine’s functionality can you begin full-fledged work.
Safety precautions
The rules and safety precautions when working with this machine are no different from working on all other machines. Below are the most important ones:
- Before starting work, check that the machine is in good working order.
- Clothes must be tucked in properly so that nothing sticks out anywhere and cannot get caught. work area machine
- You must wear a hat that will hold your hair.
- There should be a rubber mat or low wooden sheathing near the machine that will protect against electrical leakage.
- Access to the machine by children must be strictly prohibited.
- Before operating the machine, check all fasteners for their strength.
Advice: You must approach working on the machine with a clear head and understanding that if you do it incorrectly, you can cause irreparable harm to yourself.
You can find complete safety requirements for working with the machine on the World Wide Web, i.e. on the Internet and check them out.
Video reviews
Review of homemade CNC machine assembly
Video review simple machine CNC
Features Overview homemade CNC machine
Stepper Motors Overview
Review video multi-channel driver for stepper motors
IMPORTANT! Printed circuit board manufacturing on HIGH-Z series machines - a very accurate and fast process. CNC machines HIGH-Z are the best for today equipment for the production of printed circuit boards. Our machines can mill conductive strip and drill holes at the same time! Printed circuit board manufacturing technology on cnc machines HIGH-Z allows you to achieve very high milling accuracy - 0.02 millimeters. Equipment for the production of printed circuit boards is small in size.
Production of printed circuit boards on HIGH-Z machines
CN Machine LLC supplies the best German equipment for the production of printed circuit boards - CNC machines of the HIGH-Z and Raptor series. We are the official distributor of these machines in Russia.
Technology for manufacturing printed circuit boards on a cnc machine HIGH-Z
You design your PCB in PCAD for example, save the file as a .plt file (HPGL). Next you need to run the PCNC program (supplied).
For prototypes or small series, it is very important to have the ability to mill printed circuit boards. HIGH-Z cnc engraving and milling machines have the ability to mill a conductive strip with an accuracy of approximately 0.1 - 0.15 mm.
Perhaps you know on personal experience, how inconvenient the lack of milling capabilities is and what optional equipment necessary to mill PCBs yourself.
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Equipment for prototyping printed circuit boards
On milling machines With the HIGH-Z series CNC it is possible to produce prototypes of printed circuit boards for small-scale production from materials such as aluminum, textolite, fiberglass, lavsan and other fibrous materials.
Possibility to produce double-sided printed circuit boards. This video from the Perm company Uralintelcom LLC demonstrates double sided printed circuit board manufacturing process with everyone necessary operations: milling tracks, drilling holes, trimming a printed circuit board on a HIGH-ZS-400 machine. It is also possible, if necessary, to apply adhesives to the board.
For the production of printed circuit boards, a mandatory option is a mechanical depth regulator, the spring-loaded mechanism of which reads the unevenness of the surface, thereby processing the material to a clearly defined depth.