CNC PCB Engraving

As part of my final year project at the University of Reading, I was aiming to create a new soft robotic module and to apply it to the application of an emotional project robot. As part of the project, I needed to create a solenoid control circuit (your basic transistor circuit). As can be seen below I designed the PCB using Eagle CAD and managed to autoroute the traces using eagle’s auto-router which resulted in only a few jumps required. Circuit design was provided by another student and might not be correct and cause bodily harm.  


Schematic Diagram

Some of the files used can be found in the link below. Don’t take them for granted, as you can see above, this was a quick and dirty PCB design. This means there are much better ways of doing what is stated above, just this works for now …

Eagle Files and GCODE

I was having issues engraving some of the traces on the smaller CNC milling machine I have due to inconsistent z heights. I finally took the bullet and configured the controller board with the probe wiring. I then did some googling and found which would provide the code to apply the probing map to a g-code file. It seemed to work ok-ish… not sure if that was because I was using the free one. Which is kinda weird, why sell this software. The people using it are hobbyists, in this day and age most software for non-commercial use is open source. Shameless self-promotion can be found here ( The software probes the surface using the engraving tool and uses that data to adjust the height map for the engraving g-code.  However, I experienced the tool did not even cut the surface of the board and the DRO read +0.386 which did make any sense. I then manually adjusted the height and continued the program, seemed to be fine for the rest of it. Some previous, non-levelling attempts can be seen below in the gallery.