Eagle 2 GCode

I'm now in a test and trial fase for achieve good PCB boards with my CNC.

After 2 kind of failed circuits, here are my early conclusions:

Engraving at 0.2mm depth is to much. 0.1mm is to shallow in some areas due to CNC table alignment defects and the PCB raw sheet defect (it’s not perfectly flat since the board may be bend due to incorrect storage positions and handling). 0.12-0.15mm should yield the best results (still to be tested).
I'm using a 0.1mm 10º V carbide bit to do routing isolation. Applying the formula for the cutting tool wide in this wiki I should consider a minimum tool size (width) setting of 0.15-0.2mm (that also compensate the above errors plus spindle and bit run out).
To keep it simple and fast I’ll be only performing the isolation routing and skip the copper removing in bigger areas. For this pcb-gcode plugin for Eagle should have the following configs:

Tool depth for isolation and Z Down - 0.12-0.15mm (value to be tested) (Z Down is negative)
Default Isolation (*), Maximum Isolation and tool Size – 0.15-0.2mm (this will insure a single passage – the isolation routing passage).

(*) Default Isolation is the tool offset from the track. For best results this should be the same as the tool size. ALWAYS do the Clearence check in the DRC tool of EAGLE. Set the DRC checking rules in the Clearence tab to at least 2xDefault Isolation + 1xTool Size. This checks for error of overlapping that otherwise may result in the isolation routes not being generated.

Also using Voronoi-Regions gcode generetor software can be a good solution to maximize copper area and conductivity.


I’ll test some more and post the results later.