Marcos Electronic Blog: PCB: CNC

This is the second part of the practice of the PCB. In this part, our aim is to do a PBC using a CNC. A CNC Milling Machine (Computer Numerical Control). It's a machine where you put a cupper board and it mills it with the sape and the holes that you have introduced on it.

Materials:
-1 CNC
-1 Computer with Proteus
-6 Capacitors of 100nF
-1 Capacitor of 1µF
-1 Max232
-1 Power Jack DC
-1 DB9 Connector
-Male connectors for PCB

The first thing that we have to do is to go to the first part of this practice, where we finish the layout of the board in Proteus.

Once there, we will create our Gerber and Excellon files.
To do that, we will click on: Output > Generate Gerber/Excellon Files. Then, we choose the files to export and we will have some files "*.txt", compressed in zip. Those files are the layers that we chose to export, in our case, Mechanical, Botton Copper, Top Copper, Drill and Read Me.
Drill is the Excellon file, with the coordinates and the size of the holes of the board, Mechanical, Botton Copper and Top Copper are the Gerber, the parts of the track where it's needed to mill.
On the other side, Read Me is a file that do nothing and it's a sum up of the rest of the generation.

We have to take all these files to a computer with a CNC connected to it. Then, we will open the Circuit Cam, where we will convert the previous files in files that the program which controles the CNC can understand. Then, we will open the Board Master, which is a program of LPKF (the enterprise that designed our CNC) and it's a program to control it. Once there, we will open the CNC, we will introduce inside the drills, the mills and a new board. Then we will, say the machine in what positions are the different mills and drills and we will close the CNC. Finally, we will select that part we will want to do, starting with the Drill layer, then, the Top layer, then, the Bottom layer and last, the Mechanical layer. In this video, we can see a video of the drilling of the CNC:

In this other video, we can see how the CNC changes its tool:

And in this other video, we can see how the CNC makes the milling:

Then, we just have to sand the board and put some varnish over it to protect it!
Once this process has finished, we will have our board made!

Now, to finish our adapter TTL-RS232, we only have to weld the electronic components to the board. We start with the chip, then the capacitors and finally, the rest of the parts.

When we had finished all the process, we will have something like this!