Hi guys!

I am interested in 2 parts of the CNC control.

1. After I generate the gerber files from KiCad, how do I transfer them to motors in order to create an image. There are 2 or 3 motors depending on the machine, how are they translated to a decart coordinate system? How is it known which motor gets what? It should be simple coordinates to drill.

2. The mechanical part with the tubes is ambiguous, you can not connect metal to metal, there must be something in between? Where to buy the tubes and this in between from?

 

In the case of printed circuits, you need a Gerber file and a drill file at minimum.
Kicad does this for you.
The CNC controller must be capable of reading these files which essentially give the machining and drilling positions.
Not sure what is meant by 'mechanical part with the tubes' however?
Max.

 

From your many vague questions, it appears that you need to do a lot of learning about CNC in general. Is this homework? Is it about a particular installation? What kind of CNC machines are you referring to? What are the tubes you mention. There are so many un-knowns that I could not even start to answer any of your questions.
Regards,
Keith

 

From your many vague questions, it appears that you need to do a lot of learning about CNC in general. Is this homework? Is it about a particular installation? What kind of CNC machines are you referring to? What are the tubes you mention. There are so many un-knowns that I could not even start to answer any of your questions.
Regards,
Keith

Its not homework, the tubes are what moves the drill. The drill needs to move left, right, up, down, back and forth. This is done by the stepper motor, but how exactly is it translated to each stepper motor.

In the video its shown that the drill is on a tube and the motor moves the tube, at 1 min and 45 sec time.

 

Tubes? Never heard of tubes on a CNC machine.

A CNC machine likely as 4 motors: X-axis, Y-axis, Z-axis and spindle.

They are controlled by commands like this:

M3 S1000 / spindle motor on at 1000 RPM
G0 Z-2 / lower spindle by 2mm
G1 X10 Y10 F100 / move to (10,10) at 100 mm per minute

Bob

 

I assume you mean the ballscrew's when you refer to the tubes?
Machines that are dedicated to PCT board creation are designed to read the Gerber/drill files, which do resemble normal CNC language, but with some differences.
A normal CNC machine uses programs called CAD & CAM the CAD file creates the part DWG and the CAM program produces the tool paths for maching, a post processor then translates the CAM program to the format for your particular machine.
In the case of Gerber/Drill a dedicated machine is designed for this purpose.
The standard CNC language is ISO 6983.
Max.

 

I make PCBs, and quite a few other things on a CNC machine.
I use Eagle to draw the schematic and to layout the PCB.
Then pcb-gcode reads the Eagle board file and generates the G-code to isolate the tracks, etch any text, and mill any needed slots and the board outline.
Finally, I use LinxCNC to actually control the machine.
The machine is a cheap Chinese job which does a pretty good job.

The machine is the only bit which which cost money. The mentioned software is free.

pcb-gcode is the part which outlines the tracks to isolate them from the rest of the copper on the PCB. I don't use kicad so I don't know whether it is capable of this for you.

 

Kicad produces Gerber, Postscript, SVG, DXF or HPGL files.
Gerber is the version used by the board production houses.
@ArakelTheDragon what controller does your M/C have?
Max.

 

In the video its shown that the drill is on a tube and the motor moves the tube, at 1 min and 45 sec time.

Those are not tubes you see in the video. They are solid steel guides. The drill head and platform are moved by motors that rotate feed screws. You can see this in the video showing the drill head. There is a feed screw between the two steel cylindrical guides which rotates to raise and lower the head.
Keith

 

Just watched the video and now see what the OP was talking about.
@ArakelTheDragon if you want info or help on DIY CNC machine, there is the CNCzone forum which has a large following and examples of these types of machines.
Max..

 

Just watched the video and now see what the OP was talking about.
@ArakelTheDragon if you want info or help on DIY CNC machine, there is the CNCzone forum which has a large following and examples of these types of machines.
Max..

@MaxHeadRoom I tried that, but their posts have broken links and this forum seems like it will soon be gone.

@AlbertHall 200 dollars is the cheapest price I found.

I am trying to build the machine by myself, I am using a PIC MCU and I want to do it with as less materials as possible. I need to understand how this translation works in order to write the code for the post processor which will convert the gerber and drill files. I am planning on using 3 motors, 1 for the down plate of the PCB, 1 for the up and down of the drill and 1 for the left and right of the drill.

EDIT:
Like in this video, but instead of a laser, I will use a drill so I will need 2 extra motors.

 

@AlbertHall 200 dollars is the cheapest price I found.

The one I have is a CNC3020T. The precision mechanics don't come cheap. My mechanical skills are not good so the only way was to buy suitable mechanics.

 

@MaxHeadRoom I tried that, but their posts have broken links and this forum seems like it will soon be gone.

You have to be kidding! It is one of the largest forums out there with its sister site, Industry Arena, it has over 500,000 members.

The video in #11 shows some kind of toy version,
You not only need the mechanics, but CNC software to run the machine with a suitable HMI.
For the price of board with all their features such as through hole plating etc, I would not have thought it worth the effort.
If you still are determined to build, I would look at one of the kit sources, or a small ready made.
Max.

 

I may have hit the old section of the forum, but I did really try 4-5 options and they were all with broken links.

Yes I am determined to build, its better than giving 200 USD and more. Thanks for the help to everyone.

 

If you can get precision and repeatability of about 0.1 mm, good for you. I recently bought a Cheap Chinese CNC engraver. It typically crashes the USB driver of the host computer as soon as it starts milling, have bought a new (different) controller board which I am about to install. Wish me luck.

Bob

 

If you have a look at the Marlin source code for 3D printers, that may be a place to start.
https://github.com/MarlinFirmware/Marlin
This is not for PICs, but you may be able to work from it if you are a programmer. Most off it is beyond me. "My favorite programming language is Solder" is a quote I use often

 

Yes I am determined to build, its better than giving 200 USD and more.

Another project? I will ask again, knowing you won't answer, how did your do-it-yourself vacuum come out? The one you could build cheaper than buying one.

 

The motors will be with 8 steps, 45 degrees each. The circuit is ready.

I intend to use these motors, unfortunately they are very expensive and I am beginning to think the whole project will cost the same as bying it.

 

Nema 17 is 200 steps, 1.8°.

 

You go from your STL file to a program that converts it to G code and then to a board that controls the stepper motors or a servo with encoder. You can review G code by searching for it. There is any number of programs that achieve this translation. GRBL, Mach 4, TinyG, just to name a few.