2. How does it work?

The CNC Milling Process involves multi-steps and multi-pieces of software. Fortunately most, if not all, of the software is FREE! The process must start with the Design software where a 2D design of what the circuit board will ultimately look like must be initiated. Some experienced designers go right from a schematic to the software.

Below is an example of an Audio Amplifier stage employing a 2N3904 Pre-Amp stage and an LM380N-8 Audio output IC. For those who pick the fly specs out of the pepper the 2N3904 Pre-Amp stage was 1st simulated in LT Spice and has a very flat response from 300 Hertz outbound. It also is good for 45 dB of gain. So please do not email me that you don't like the bias resistors or operating point. It does just fine! Simulate the circuit in LT Spice first before emailing me. This amp stage is better than 1 watt of output!

I personally like to use graph paper to hand lay out the cicruit first and then using coordinates from the graph paper transfer that to the design program.

In the hand sketch above the 4X4 matrix is the 2N3904 stage and the 6 pads in the center are for an 8 pin DIP. Pins 4 and 5 of the LM-380N-8 are grounded so simply are soldered to the PC Board. I use an 8 Pin (Machined Pin) DIP Socket.

Deisgn Systems I have used include G Simple and Carbide Create. Once the design is completed then the next step is to create the G Code or GRBL Code that is read by the CNC Milling Machine. Other machine codes exist but often when the CNC Milling machine is purchased these are the commom codes red by the machines. Don't gulp too hard but some CNC Mills are run by an Arduino which reads the GRBL code. The MACH III software, which has professional production run variants uses the G-Code. My CNC Mill was homebrewed by my son and uses the MACH III software.

In Carbide Create it can generte both the G-Code or the GRBL codes with just a mouse click. With G-Simple you create an interim .dxf file which then must use another program dxf2gcode to generate the G Code. Finally the CNC Mill itself has software which takes the G-Code or GRBL code and coverts it into the actual machine actions.

Below are two design outputs with the one on the left being G Simple and the one on the right being Carbide Create. The shocker -- I can take a .dxf file generated in G Simple and it can be read by Carbide Create. So essentially all of my old G Simple designs can be moved over to Carbide Create.